Add BC6H support in the image importer. ASTC is next

AnKi/Importer/ImageImporter.cpp

@@ -4,6 +4,7 @@
 // http://www.anki3d.org/LICENSE
 
 #include <AnKi/Importer/ImageImporter.h>
+#include <AnKi/Importer/TinyExr.h>
 #include <AnKi/Gr/Common.h>
 #include <AnKi/Resource/Stb.h>
 #include <AnKi/Util/Process.h>
@@ -32,6 +33,7 @@ public:
 class Mipmap
 {
 public:
+	/// One surface for each layer ore one per face or a single volume if it's a 3D texture.
 	DynamicArrayAuto<SurfaceOrVolumeData> m_surfacesOrVolume;
 
 	Mipmap(GenericMemoryPoolAllocator<U8> alloc)
@@ -51,7 +53,8 @@ public:
 	U32 m_faceCount = 0;
 	U32 m_layerCount = 0;
 	U32 m_channelCount = 0;
-	U32 m_pixelSize = 0;
+	U32 m_pixelSize = 0; ///< Texel size of an uncompressed image.
+	Bool m_hdr = false;
 
 	ImageImporterContext(GenericMemoryPoolAllocator<U8> alloc)
 		: m_mipmaps(alloc)
@@ -186,11 +189,13 @@ static ANKI_USE_RESULT Error checkConfig(const ImageImporterConfig& config)
 }
 
 static ANKI_USE_RESULT Error checkInputImages(const ImageImporterConfig& config, U32& width, U32& height,
-											  U32& channelCount)
+											  U32& channelCount, Bool& isHdr)
 {
 	width = 0;
 	height = 0;
 	channelCount = 0;
+	isHdr = false;
+	I isHdr2 = -1;
 
 	for(U32 i = 0; i < config.m_inputFilenames.getSize(); ++i)
 	{
@@ -214,6 +219,19 @@ static ANKI_USE_RESULT Error checkInputImages(const ImageImporterConfig& config,
 							   config.m_inputFilenames[i].cstr());
 			return Error::USER_DATA;
 		}
+
+		const I hdr = stbi_is_hdr(config.m_inputFilenames[i].cstr());
+		if(isHdr2 < 0)
+		{
+			isHdr2 = hdr;
+			isHdr = hdr != 0;
+		}
+		else if(hdr != isHdr2)
+		{
+			ANKI_IMPORTER_LOGE("Input image doesn't match previous HDR parameters: %s",
+							   config.m_inputFilenames[i].cstr());
+			return Error::USER_DATA;
+		}
 	}
 
 	ANKI_ASSERT(width > 0 && height > 0 && channelCount > 0);
@@ -241,6 +259,7 @@ static ANKI_USE_RESULT Error loadFirstMipmap(const ImageImporterConfig& config,
 	else
 	{
 		mip0.m_surfacesOrVolume.create(ctx.m_faceCount * ctx.m_layerCount, alloc);
+		ANKI_ASSERT(mip0.m_surfacesOrVolume.getSize() == config.m_inputFilenames.getSize());
 
 		for(U32 f = 0; f < ctx.m_faceCount; ++f)
 		{
@@ -256,8 +275,17 @@ static ANKI_USE_RESULT Error loadFirstMipmap(const ImageImporterConfig& config,
 	{
 		I32 width, height, c;
 		stbi_set_flip_vertically_on_load_thread(true);
-		void* data = stbi_load(config.m_inputFilenames[i].cstr(), &width, &height, &c, ctx.m_channelCount);
+		void* data;
+		if(!ctx.m_hdr)
+		{
+			data = stbi_load(config.m_inputFilenames[i].cstr(), &width, &height, &c, ctx.m_channelCount);
+		}
+		else
+		{
+			data = stbi_loadf(config.m_inputFilenames[i].cstr(), &width, &height, &c, ctx.m_channelCount);
+		}
 		ANKI_ASSERT(U32(c) == ctx.m_channelCount);
+
 		if(!data)
 		{
 			ANKI_IMPORTER_LOGE("STB load failed: %s", config.m_inputFilenames[i].cstr());
@@ -272,13 +300,7 @@ static ANKI_USE_RESULT Error loadFirstMipmap(const ImageImporterConfig& config,
 		}
 		else
 		{
-			for(U32 l = 0; l < ctx.m_layerCount; ++l)
-			{
-				for(U32 f = 0; f < ctx.m_faceCount; ++f)
-				{
-					memcpy(mip0.m_surfacesOrVolume[l * ctx.m_faceCount + f].m_pixels.getBegin(), data, dataSize);
-				}
-			}
+			memcpy(mip0.m_surfacesOrVolume[i].m_pixels.getBegin(), data, dataSize);
 		}
 
 		stbi_image_free(data);
@@ -287,17 +309,17 @@ static ANKI_USE_RESULT Error loadFirstMipmap(const ImageImporterConfig& config,
 	return Error::NONE;
 }
 
-template<U32 TCHANNEL_COUNT>
+template<typename TStorageVec>
 static void generateSurfaceMipmap(ConstWeakArray<U8, PtrSize> inBuffer, U32 inWidth, U32 inHeight,
 								  WeakArray<U8, PtrSize> outBuffer)
 {
-	using UVecType = typename std::conditional_t<TCHANNEL_COUNT == 3, U8Vec3, U8Vec4>;
-	using FVecType = typename std::conditional_t<TCHANNEL_COUNT == 3, Vec3, Vec4>;
+	constexpr U32 channelCount = TStorageVec::getSize();
+	using FVecType = typename std::conditional_t<channelCount == 3, Vec3, Vec4>;
 
-	const ConstWeakArray<UVecType, PtrSize> inPixels(reinterpret_cast<const UVecType*>(&inBuffer[0]),
-													 inBuffer.getSizeInBytes() / sizeof(UVecType));
-	WeakArray<UVecType, PtrSize> outPixels(reinterpret_cast<UVecType*>(&outBuffer[0]),
-										   outBuffer.getSizeInBytes() / sizeof(UVecType));
+	const ConstWeakArray<TStorageVec, PtrSize> inPixels(reinterpret_cast<const TStorageVec*>(&inBuffer[0]),
+														inBuffer.getSizeInBytes() / sizeof(TStorageVec));
+	WeakArray<TStorageVec, PtrSize> outPixels(reinterpret_cast<TStorageVec*>(&outBuffer[0]),
+											  outBuffer.getSizeInBytes() / sizeof(TStorageVec));
 
 	const U32 outWidth = inWidth >> 1;
 	const U32 outHeight = inHeight >> 1;
@@ -313,18 +335,18 @@ static void generateSurfaceMipmap(ConstWeakArray<U8, PtrSize> inBuffer, U32 inWi
 				for(U32 x = 0; x < 2; ++x)
 				{
 					const U32 idx = (h * 2 + y) * inWidth + (w * 2 + x);
-					const UVecType inPixel = inPixels[idx];
-					for(U32 c = 0; c < TCHANNEL_COUNT; ++c)
+					const TStorageVec inPixel = inPixels[idx];
+					for(U32 c = 0; c < channelCount; ++c)
 					{
-						average[c] += F32(inPixel[c]) / 255.0f * 0.25f;
+						average[c] += F32(inPixel[c]) * 0.25f;
 					}
 				}
 			}
 
-			UVecType uaverage;
-			for(U32 c = 0; c < TCHANNEL_COUNT; ++c)
+			TStorageVec uaverage;
+			for(U32 c = 0; c < channelCount; ++c)
 			{
-				uaverage[c] = U8(average[c] * 255.0f);
+				uaverage[c] = typename TStorageVec::Scalar(average[c]);
 			}
 
 			// Store
@@ -336,22 +358,37 @@ static void generateSurfaceMipmap(ConstWeakArray<U8, PtrSize> inBuffer, U32 inWi
 
 static ANKI_USE_RESULT Error compressS3tc(GenericMemoryPoolAllocator<U8> alloc, CString tempDirectory,
 										  CString compressonatorPath, ConstWeakArray<U8, PtrSize> inPixels, U32 inWidth,
-										  U32 inHeight, U32 channelCount, WeakArray<U8, PtrSize> outPixels)
+										  U32 inHeight, U32 channelCount, Bool hdr, WeakArray<U8, PtrSize> outPixels)
 {
-	ANKI_ASSERT(inPixels.getSizeInBytes() == PtrSize(inWidth) * inHeight * channelCount);
+	ANKI_ASSERT(inPixels.getSizeInBytes()
+				== PtrSize(inWidth) * inHeight * channelCount * ((hdr) ? sizeof(F32) : sizeof(U8)));
 	ANKI_ASSERT(inWidth > 0 && isPowerOfTwo(inWidth) && inHeight > 0 && isPowerOfTwo(inHeight));
-	ANKI_ASSERT(outPixels.getSizeInBytes() == PtrSize((channelCount == 3) ? 8 : 16) * (inWidth / 4) * (inHeight / 4));
+	ANKI_ASSERT(outPixels.getSizeInBytes()
+				== PtrSize((hdr || channelCount == 4) ? 16 : 8) * (inWidth / 4) * (inHeight / 4));
 
 	// Create a PNG image to feed to the compressor
-	StringAuto pngFilename(alloc);
-	pngFilename.sprintf("%s/AnKiImageImporter_%u.png", tempDirectory.cstr(), U32(std::rand()));
-	ANKI_IMPORTER_LOGV("Will store: %s", pngFilename.cstr());
-	if(!stbi_write_png(pngFilename.cstr(), inWidth, inHeight, channelCount, inPixels.getBegin(), 0))
+	StringAuto tmpFilename(alloc);
+	tmpFilename.sprintf("%s/AnKiImageImporter_%u.%s", tempDirectory.cstr(), U32(std::rand()), (hdr) ? "exr" : "png");
+	ANKI_IMPORTER_LOGV("Will store: %s", tmpFilename.cstr());
+	Bool saveTmpImageOk = false;
+	if(!hdr)
 	{
-		ANKI_IMPORTER_LOGE("STB failed to create: %s", pngFilename.cstr());
+		const I ok = stbi_write_png(tmpFilename.cstr(), inWidth, inHeight, channelCount, inPixels.getBegin(), 0);
+		saveTmpImageOk = !!ok;
+	}
+	else
+	{
+		const I ret = SaveEXR(reinterpret_cast<const F32*>(inPixels.getBegin()), inWidth, inHeight, channelCount, 0,
+							  tmpFilename.cstr(), nullptr);
+		saveTmpImageOk = ret >= 0;
+	}
+
+	if(!saveTmpImageOk)
+	{
+		ANKI_IMPORTER_LOGE("Failed to create: %s", tmpFilename.cstr());
 		return Error::FUNCTION_FAILED;
 	}
-	CleanupFile pngCleanup(alloc, pngFilename);
+	CleanupFile tmpCleanup(alloc, tmpFilename);
 
 	// Invoke the compressor process
 	StringAuto ddsFilename(alloc);
@@ -361,8 +398,8 @@ static ANKI_USE_RESULT Error compressS3tc(GenericMemoryPoolAllocator<U8> alloc,
 	U32 argCount = 0;
 	args[argCount++] = "-nomipmap";
 	args[argCount++] = "-fd";
-	args[argCount++] = (channelCount == 3) ? "BC1" : "BC3";
-	args[argCount++] = pngFilename;
+	args[argCount++] = (hdr) ? "BC6H" : ((channelCount == 3) ? "BC1" : "BC3");
+	args[argCount++] = tmpFilename;
 	args[argCount++] = ddsFilename;
 
 	ANKI_IMPORTER_LOGV("Will invoke process: CompressonatorCLI %s %s %s %s %s", args[0].cstr(), args[1].cstr(),
@@ -398,18 +435,24 @@ static ANKI_USE_RESULT Error compressS3tc(GenericMemoryPoolAllocator<U8> alloc,
 	DdsHeader ddsHeader;
 	ANKI_CHECK(ddsFile.read(&ddsHeader, sizeof(DdsHeader)));
 
-	if(channelCount == 3 && memcmp(&ddsHeader.m_ddspf.m_dwFourCC[0], "DXT1", 4) != 0)
+	if(!hdr && channelCount == 3 && memcmp(&ddsHeader.m_ddspf.m_dwFourCC[0], "DXT1", 4) != 0)
 	{
 		ANKI_IMPORTER_LOGE("Incorrect format. Expecting DXT1");
 		return Error::FUNCTION_FAILED;
 	}
 
-	if(channelCount == 4 && memcmp(&ddsHeader.m_ddspf.m_dwFourCC[0], "DXT5", 4) != 0)
+	if(!hdr && channelCount == 4 && memcmp(&ddsHeader.m_ddspf.m_dwFourCC[0], "DXT5", 4) != 0)
 	{
 		ANKI_IMPORTER_LOGE("Incorrect format. Expecting DXT5");
 		return Error::FUNCTION_FAILED;
 	}
 
+	if(hdr && memcmp(&ddsHeader.m_ddspf.m_dwFourCC[0], "DX10", 4) != 0)
+	{
+		ANKI_IMPORTER_LOGE("Incorrect format. Expecting BC6H");
+		return Error::FUNCTION_FAILED;
+	}
+
 	if(ddsHeader.m_dwWidth != inWidth || ddsHeader.m_dwHeight != inHeight)
 	{
 		ANKI_IMPORTER_LOGE("Incorrect DDS image size");
@@ -615,7 +658,8 @@ static ANKI_USE_RESULT Error importImageInternal(const ImageImporterConfig& conf
 	// Checks
 	ANKI_CHECK(checkConfig(config));
 	U32 width, height, channelCount;
-	ANKI_CHECK(checkInputImages(config, width, height, channelCount));
+	Bool isHdr;
+	ANKI_CHECK(checkInputImages(config, width, height, channelCount, isHdr));
 
 	// Init image
 	GenericMemoryPoolAllocator<U8> alloc = config.m_allocator;
@@ -626,9 +670,20 @@ static ANKI_USE_RESULT Error importImageInternal(const ImageImporterConfig& conf
 	ctx.m_depth = (config.m_type == ImageBinaryType::_3D) ? config.m_inputFilenames.getSize() : 1;
 	ctx.m_faceCount = (config.m_type == ImageBinaryType::CUBE) ? 6 : 1;
 	ctx.m_layerCount = (config.m_type == ImageBinaryType::_2D_ARRAY) ? config.m_inputFilenames.getSize() : 1;
+	ctx.m_hdr = isHdr;
 
 	U32 desiredChannelCount;
-	if(config.m_noAlpha || channelCount == 1)
+	if(isHdr && !!(config.m_compressions & ImageBinaryDataCompression::S3TC))
+	{
+		// BC6H doesn't have a 4th channel
+		if(channelCount != 3)
+		{
+			ANKI_IMPORTER_LOGW("Input images have alpha but that can't be supported with BC6H");
+		}
+
+		desiredChannelCount = 3;
+	}
+	else if(config.m_noAlpha || channelCount == 1)
 	{
 		// no alpha or 1 component grey
 		desiredChannelCount = 3;
@@ -644,7 +699,7 @@ static ANKI_USE_RESULT Error importImageInternal(const ImageImporterConfig& conf
 	}
 
 	ctx.m_channelCount = desiredChannelCount;
-	ctx.m_pixelSize = ctx.m_channelCount;
+	ctx.m_pixelSize = ctx.m_channelCount * ((isHdr) ? sizeof(F32) : sizeof(U8));
 
 	// Load first mip from the files
 	ANKI_CHECK(loadFirstMipmap(config, ctx));
@@ -679,16 +734,35 @@ static ANKI_USE_RESULT Error importImageInternal(const ImageImporterConfig& conf
 
 					if(ctx.m_channelCount == 3)
 					{
-						generateSurfaceMipmap<3>(ConstWeakArray<U8, PtrSize>(inSurface.m_pixels),
-												 ctx.m_width >> (mip - 1), ctx.m_height >> (mip - 1),
-												 WeakArray<U8, PtrSize>(outSurface.m_pixels));
+						if(ctx.m_hdr)
+						{
+							generateSurfaceMipmap<Vec3>(ConstWeakArray<U8, PtrSize>(inSurface.m_pixels),
+														ctx.m_width >> (mip - 1), ctx.m_height >> (mip - 1),
+														WeakArray<U8, PtrSize>(outSurface.m_pixels));
+						}
+						else
+						{
+							generateSurfaceMipmap<U8Vec3>(ConstWeakArray<U8, PtrSize>(inSurface.m_pixels),
+														  ctx.m_width >> (mip - 1), ctx.m_height >> (mip - 1),
+														  WeakArray<U8, PtrSize>(outSurface.m_pixels));
+						}
 					}
 					else
 					{
 						ANKI_ASSERT(ctx.m_channelCount == 4);
-						generateSurfaceMipmap<4>(ConstWeakArray<U8, PtrSize>(inSurface.m_pixels),
-												 ctx.m_width >> (mip - 1), ctx.m_height >> (mip - 1),
-												 WeakArray<U8, PtrSize>(outSurface.m_pixels));
+
+						if(ctx.m_hdr)
+						{
+							generateSurfaceMipmap<Vec4>(ConstWeakArray<U8, PtrSize>(inSurface.m_pixels),
+														ctx.m_width >> (mip - 1), ctx.m_height >> (mip - 1),
+														WeakArray<U8, PtrSize>(outSurface.m_pixels));
+						}
+						else
+						{
+							generateSurfaceMipmap<U8Vec4>(ConstWeakArray<U8, PtrSize>(inSurface.m_pixels),
+														  ctx.m_width >> (mip - 1), ctx.m_height >> (mip - 1),
+														  WeakArray<U8, PtrSize>(outSurface.m_pixels));
+						}
 					}
 				}
 			}
@@ -715,14 +789,15 @@ static ANKI_USE_RESULT Error importImageInternal(const ImageImporterConfig& conf
 
 					const U32 width = ctx.m_width >> mip;
 					const U32 height = ctx.m_height >> mip;
-					const PtrSize blockSize = (ctx.m_channelCount == 3) ? 8 : 16;
+					const PtrSize blockSize = (ctx.m_hdr || ctx.m_channelCount == 4) ? 16 : 8;
 					const PtrSize s3tcImageSize = blockSize * (width / 4) * (height / 4);
 
 					surface.m_s3tcPixels.create(s3tcImageSize);
 
 					ANKI_CHECK(compressS3tc(alloc, config.m_tempDirectory, config.m_compressonatorPath,
 											ConstWeakArray<U8, PtrSize>(surface.m_pixels), width, height,
-											ctx.m_channelCount, WeakArray<U8, PtrSize>(surface.m_s3tcPixels)));
+											ctx.m_channelCount, ctx.m_hdr,
+											WeakArray<U8, PtrSize>(surface.m_s3tcPixels)));
 				}
 			}
 		}
@@ -730,6 +805,7 @@ static ANKI_USE_RESULT Error importImageInternal(const ImageImporterConfig& conf
 
 	if(!!(config.m_compressions & ImageBinaryDataCompression::ASTC))
 	{
+		ANKI_ASSERT(!ctx.m_hdr && "TODO");
 		ANKI_IMPORTER_LOGV("Will compress in ASTC");
 
 		for(U32 mip = 0; mip < mipCount; ++mip)

AnKi/Importer/TinyExr.cpp

@@ -0,0 +1,22 @@
+// Copyright (C) 2009-2022, Panagiotis Christopoulos Charitos and contributors.
+// All rights reserved.
+// Code licensed under the BSD License.
+// http://www.anki3d.org/LICENSE
+
+#include <AnKi/Config.h>
+#include <ThirdParty/ZLib/zlib.h>
+
+#define TINYEXR_USE_MINIZ 0
+#define TINYEXR_IMPLEMENTATION 1
+
+#if ANKI_COMPILER_GCC_COMPATIBLE
+#	pragma GCC diagnostic push
+#	pragma GCC diagnostic ignored "-Wunused-but-set-variable"
+#	pragma GCC diagnostic ignored "-Wunused-function"
+#endif
+
+#include <ThirdParty/TinyExr/tinyexr.h>
+
+#if ANKI_COMPILER_GCC_COMPATIBLE
+#	pragma GCC diagnostic pop
+#endif

AnKi/Importer/TinyExr.h

@@ -0,0 +1,7 @@
+// Copyright (C) 2009-2022, Panagiotis Christopoulos Charitos and contributors.
+// All rights reserved.
+// Code licensed under the BSD License.
+// http://www.anki3d.org/LICENSE
+
+#define TINYEXR_USE_MINIZ 0
+#include <ThirdParty/TinyExr/tinyexr.h>

ThirdParty/TinyExr/tinyexr.h

@@ -0,0 +1,8601 @@
+#ifndef TINYEXR_H_
+#define TINYEXR_H_
+/*
+Copyright (c) 2014 - 2021, Syoyo Fujita and many contributors.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+    * Neither the name of the Syoyo Fujita nor the
+      names of its contributors may be used to endorse or promote products
+      derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
+DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+// TinyEXR contains some OpenEXR code, which is licensed under ------------
+
+///////////////////////////////////////////////////////////////////////////
+//
+// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
+// Digital Ltd. LLC
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+// *       Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// *       Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// *       Neither the name of Industrial Light & Magic nor the names of
+// its contributors may be used to endorse or promote products derived
+// from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+///////////////////////////////////////////////////////////////////////////
+
+// End of OpenEXR license -------------------------------------------------
+
+
+//
+//
+//   Do this:
+//    #define TINYEXR_IMPLEMENTATION
+//   before you include this file in *one* C or C++ file to create the
+//   implementation.
+//
+//   // i.e. it should look like this:
+//   #include ...
+//   #include ...
+//   #include ...
+//   #define TINYEXR_IMPLEMENTATION
+//   #include "tinyexr.h"
+//
+//
+
+#include <stddef.h>  // for size_t
+#include <stdint.h>  // guess stdint.h is available(C99)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if defined(_M_IX86) || defined(_M_X64) || defined(__i386__) || \
+    defined(__i386) || defined(__i486__) || defined(__i486) ||  \
+    defined(i386) || defined(__ia64__) || defined(__x86_64__)
+#define TINYEXR_X86_OR_X64_CPU 1
+#else
+#define TINYEXR_X86_OR_X64_CPU 0
+#endif
+
+#if (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) || TINYEXR_X86_OR_X64_CPU
+#define TINYEXR_LITTLE_ENDIAN 1
+#else
+#define TINYEXR_LITTLE_ENDIAN 0
+#endif
+
+// Use miniz or not to decode ZIP format pixel. Linking with zlib
+// required if this flas is 0.
+#ifndef TINYEXR_USE_MINIZ
+#define TINYEXR_USE_MINIZ (1)
+#endif
+
+// Disable PIZ comporession when applying cpplint.
+#ifndef TINYEXR_USE_PIZ
+#define TINYEXR_USE_PIZ (1)
+#endif
+
+#ifndef TINYEXR_USE_ZFP
+#define TINYEXR_USE_ZFP (0)  // TinyEXR extension.
+// http://computation.llnl.gov/projects/floating-point-compression
+#endif
+
+#ifndef TINYEXR_USE_THREAD
+#define TINYEXR_USE_THREAD (0)  // No threaded loading.
+// http://computation.llnl.gov/projects/floating-point-compression
+#endif
+
+#ifndef TINYEXR_USE_OPENMP
+#ifdef _OPENMP
+#define TINYEXR_USE_OPENMP (1)
+#else
+#define TINYEXR_USE_OPENMP (0)
+#endif
+#endif
+
+#define TINYEXR_SUCCESS (0)
+#define TINYEXR_ERROR_INVALID_MAGIC_NUMBER (-1)
+#define TINYEXR_ERROR_INVALID_EXR_VERSION (-2)
+#define TINYEXR_ERROR_INVALID_ARGUMENT (-3)
+#define TINYEXR_ERROR_INVALID_DATA (-4)
+#define TINYEXR_ERROR_INVALID_FILE (-5)
+#define TINYEXR_ERROR_INVALID_PARAMETER (-6)
+#define TINYEXR_ERROR_CANT_OPEN_FILE (-7)
+#define TINYEXR_ERROR_UNSUPPORTED_FORMAT (-8)
+#define TINYEXR_ERROR_INVALID_HEADER (-9)
+#define TINYEXR_ERROR_UNSUPPORTED_FEATURE (-10)
+#define TINYEXR_ERROR_CANT_WRITE_FILE (-11)
+#define TINYEXR_ERROR_SERIALZATION_FAILED (-12)
+#define TINYEXR_ERROR_LAYER_NOT_FOUND (-13)
+
+// @note { OpenEXR file format: http://www.openexr.com/openexrfilelayout.pdf }
+
+// pixel type: possible values are: UINT = 0 HALF = 1 FLOAT = 2
+#define TINYEXR_PIXELTYPE_UINT (0)
+#define TINYEXR_PIXELTYPE_HALF (1)
+#define TINYEXR_PIXELTYPE_FLOAT (2)
+
+#define TINYEXR_MAX_HEADER_ATTRIBUTES (1024)
+#define TINYEXR_MAX_CUSTOM_ATTRIBUTES (128)
+
+#define TINYEXR_COMPRESSIONTYPE_NONE (0)
+#define TINYEXR_COMPRESSIONTYPE_RLE (1)
+#define TINYEXR_COMPRESSIONTYPE_ZIPS (2)
+#define TINYEXR_COMPRESSIONTYPE_ZIP (3)
+#define TINYEXR_COMPRESSIONTYPE_PIZ (4)
+#define TINYEXR_COMPRESSIONTYPE_ZFP (128)  // TinyEXR extension
+
+#define TINYEXR_ZFP_COMPRESSIONTYPE_RATE (0)
+#define TINYEXR_ZFP_COMPRESSIONTYPE_PRECISION (1)
+#define TINYEXR_ZFP_COMPRESSIONTYPE_ACCURACY (2)
+
+#define TINYEXR_TILE_ONE_LEVEL (0)
+#define TINYEXR_TILE_MIPMAP_LEVELS (1)
+#define TINYEXR_TILE_RIPMAP_LEVELS (2)
+
+#define TINYEXR_TILE_ROUND_DOWN (0)
+#define TINYEXR_TILE_ROUND_UP (1)
+
+typedef struct _EXRVersion {
+  int version;    // this must be 2
+  // tile format image;
+  // not zero for only a single-part "normal" tiled file (according to spec.)
+  int tiled;      
+  int long_name;  // long name attribute
+  // deep image(EXR 2.0);
+  // for a multi-part file, indicates that at least one part is of type deep* (according to spec.)
+  int non_image;  
+  int multipart;  // multi-part(EXR 2.0)
+} EXRVersion;
+
+typedef struct _EXRAttribute {
+  char name[256];  // name and type are up to 255 chars long.
+  char type[256];
+  unsigned char *value;  // uint8_t*
+  int size;
+  int pad0;
+} EXRAttribute;
+
+typedef struct _EXRChannelInfo {
+  char name[256];  // less than 255 bytes long
+  int pixel_type;
+  int x_sampling;
+  int y_sampling;
+  unsigned char p_linear;
+  unsigned char pad[3];
+} EXRChannelInfo;
+
+typedef struct _EXRTile {
+  int offset_x;
+  int offset_y;
+  int level_x;
+  int level_y;
+
+  int width;   // actual width in a tile.
+  int height;  // actual height int a tile.
+
+  unsigned char **images;  // image[channels][pixels]
+} EXRTile;
+
+typedef struct _EXRBox2i {
+  int min_x;
+  int min_y;
+  int max_x;
+  int max_y;
+} EXRBox2i;
+
+typedef struct _EXRHeader {
+  float pixel_aspect_ratio;
+  int line_order;
+  EXRBox2i data_window;
+  EXRBox2i display_window;
+  float screen_window_center[2];
+  float screen_window_width;
+
+  int chunk_count;
+
+  // Properties for tiled format(`tiledesc`).
+  int tiled;
+  int tile_size_x;
+  int tile_size_y;
+  int tile_level_mode;
+  int tile_rounding_mode;
+
+  int long_name;
+  // for a single-part file, agree with the version field bit 11
+  // for a multi-part file, it is consistent with the type of part
+  int non_image;
+  int multipart;
+  unsigned int header_len;
+
+  // Custom attributes(exludes required attributes(e.g. `channels`,
+  // `compression`, etc)
+  int num_custom_attributes;
+  EXRAttribute *custom_attributes;  // array of EXRAttribute. size =
+                                    // `num_custom_attributes`.
+
+  EXRChannelInfo *channels;  // [num_channels]
+
+  int *pixel_types;  // Loaded pixel type(TINYEXR_PIXELTYPE_*) of `images` for
+  // each channel. This is overwritten with `requested_pixel_types` when
+  // loading.
+  int num_channels;
+
+  int compression_type;        // compression type(TINYEXR_COMPRESSIONTYPE_*)
+  int *requested_pixel_types;  // Filled initially by
+                               // ParseEXRHeaderFrom(Meomory|File), then users
+                               // can edit it(only valid for HALF pixel type
+                               // channel)
+  // name attribute required for multipart files;
+  // must be unique and non empty (according to spec.);
+  // use EXRSetNameAttr for setting value;
+  // max 255 character allowed - excluding terminating zero
+  char name[256];
+} EXRHeader;
+
+typedef struct _EXRMultiPartHeader {
+  int num_headers;
+  EXRHeader *headers;
+
+} EXRMultiPartHeader;
+
+typedef struct _EXRImage {
+  EXRTile *tiles;  // Tiled pixel data. The application must reconstruct image
+                   // from tiles manually. NULL if scanline format.
+  struct _EXRImage* next_level; // NULL if scanline format or image is the last level.
+  int level_x; // x level index
+  int level_y; // y level index
+
+  unsigned char **images;  // image[channels][pixels]. NULL if tiled format.
+
+  int width;
+  int height;
+  int num_channels;
+
+  // Properties for tile format.
+  int num_tiles;
+
+} EXRImage;
+
+typedef struct _EXRMultiPartImage {
+  int num_images;
+  EXRImage *images;
+
+} EXRMultiPartImage;
+
+typedef struct _DeepImage {
+  const char **channel_names;
+  float ***image;      // image[channels][scanlines][samples]
+  int **offset_table;  // offset_table[scanline][offsets]
+  int num_channels;
+  int width;
+  int height;
+  int pad0;
+} DeepImage;
+
+// @deprecated { For backward compatibility. Not recommended to use. }
+// Loads single-frame OpenEXR image. Assume EXR image contains A(single channel
+// alpha) or RGB(A) channels.
+// Application must free image data as returned by `out_rgba`
+// Result image format is: float x RGBA x width x hight
+// Returns negative value and may set error string in `err` when there's an
+// error
+extern int LoadEXR(float **out_rgba, int *width, int *height,
+                   const char *filename, const char **err);
+
+// Loads single-frame OpenEXR image by specifying layer name. Assume EXR image
+// contains A(single channel alpha) or RGB(A) channels. Application must free
+// image data as returned by `out_rgba` Result image format is: float x RGBA x
+// width x hight Returns negative value and may set error string in `err` when
+// there's an error When the specified layer name is not found in the EXR file,
+// the function will return `TINYEXR_ERROR_LAYER_NOT_FOUND`.
+extern int LoadEXRWithLayer(float **out_rgba, int *width, int *height,
+                            const char *filename, const char *layer_name,
+                            const char **err);
+
+//
+// Get layer infos from EXR file.
+//
+// @param[out] layer_names List of layer names. Application must free memory
+// after using this.
+// @param[out] num_layers The number of layers
+// @param[out] err Error string(will be filled when the function returns error
+// code). Free it using FreeEXRErrorMessage after using this value.
+//
+// @return TINYEXR_SUCCEES upon success.
+//
+extern int EXRLayers(const char *filename, const char **layer_names[],
+                     int *num_layers, const char **err);
+
+// @deprecated { to be removed. }
+// Simple wrapper API for ParseEXRHeaderFromFile.
+// checking given file is a EXR file(by just look up header)
+// @return TINYEXR_SUCCEES for EXR image, TINYEXR_ERROR_INVALID_HEADER for
+// others
+extern int IsEXR(const char *filename);
+
+// @deprecated { to be removed. }
+// Saves single-frame OpenEXR image. Assume EXR image contains RGB(A) channels.
+// components must be 1(Grayscale), 3(RGB) or 4(RGBA).
+// Input image format is: `float x width x height`, or `float x RGB(A) x width x
+// hight`
+// Save image as fp16(HALF) format when `save_as_fp16` is positive non-zero
+// value.
+// Save image as fp32(FLOAT) format when `save_as_fp16` is 0.
+// Use ZIP compression by default.
+// Returns negative value and may set error string in `err` when there's an
+// error
+extern int SaveEXR(const float *data, const int width, const int height,
+                   const int components, const int save_as_fp16,
+                   const char *filename, const char **err);
+
+// Returns the number of resolution levels of the image (including the base)
+extern int EXRNumLevels(const EXRImage* exr_image);
+
+// Initialize EXRHeader struct
+extern void InitEXRHeader(EXRHeader *exr_header);
+
+// Set name attribute of EXRHeader struct (it makes a copy)
+extern void EXRSetNameAttr(EXRHeader *exr_header, const char* name);
+
+// Initialize EXRImage struct
+extern void InitEXRImage(EXRImage *exr_image);
+
+// Frees internal data of EXRHeader struct
+extern int FreeEXRHeader(EXRHeader *exr_header);
+
+// Frees internal data of EXRImage struct
+extern int FreeEXRImage(EXRImage *exr_image);
+
+// Frees error message
+extern void FreeEXRErrorMessage(const char *msg);
+
+// Parse EXR version header of a file.
+extern int ParseEXRVersionFromFile(EXRVersion *version, const char *filename);
+
+// Parse EXR version header from memory-mapped EXR data.
+extern int ParseEXRVersionFromMemory(EXRVersion *version,
+                                     const unsigned char *memory, size_t size);
+
+// Parse single-part OpenEXR header from a file and initialize `EXRHeader`.
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int ParseEXRHeaderFromFile(EXRHeader *header, const EXRVersion *version,
+                                  const char *filename, const char **err);
+
+// Parse single-part OpenEXR header from a memory and initialize `EXRHeader`.
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int ParseEXRHeaderFromMemory(EXRHeader *header,
+                                    const EXRVersion *version,
+                                    const unsigned char *memory, size_t size,
+                                    const char **err);
+
+// Parse multi-part OpenEXR headers from a file and initialize `EXRHeader*`
+// array.
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int ParseEXRMultipartHeaderFromFile(EXRHeader ***headers,
+                                           int *num_headers,
+                                           const EXRVersion *version,
+                                           const char *filename,
+                                           const char **err);
+
+// Parse multi-part OpenEXR headers from a memory and initialize `EXRHeader*`
+// array
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int ParseEXRMultipartHeaderFromMemory(EXRHeader ***headers,
+                                             int *num_headers,
+                                             const EXRVersion *version,
+                                             const unsigned char *memory,
+                                             size_t size, const char **err);
+
+// Loads single-part OpenEXR image from a file.
+// Application must setup `ParseEXRHeaderFromFile` before calling this function.
+// Application can free EXRImage using `FreeEXRImage`
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int LoadEXRImageFromFile(EXRImage *image, const EXRHeader *header,
+                                const char *filename, const char **err);
+
+// Loads single-part OpenEXR image from a memory.
+// Application must setup `EXRHeader` with
+// `ParseEXRHeaderFromMemory` before calling this function.
+// Application can free EXRImage using `FreeEXRImage`
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int LoadEXRImageFromMemory(EXRImage *image, const EXRHeader *header,
+                                  const unsigned char *memory,
+                                  const size_t size, const char **err);
+
+// Loads multi-part OpenEXR image from a file.
+// Application must setup `ParseEXRMultipartHeaderFromFile` before calling this
+// function.
+// Application can free EXRImage using `FreeEXRImage`
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int LoadEXRMultipartImageFromFile(EXRImage *images,
+                                         const EXRHeader **headers,
+                                         unsigned int num_parts,
+                                         const char *filename,
+                                         const char **err);
+
+// Loads multi-part OpenEXR image from a memory.
+// Application must setup `EXRHeader*` array with
+// `ParseEXRMultipartHeaderFromMemory` before calling this function.
+// Application can free EXRImage using `FreeEXRImage`
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int LoadEXRMultipartImageFromMemory(EXRImage *images,
+                                           const EXRHeader **headers,
+                                           unsigned int num_parts,
+                                           const unsigned char *memory,
+                                           const size_t size, const char **err);
+
+// Saves multi-channel, single-frame OpenEXR image to a file.
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int SaveEXRImageToFile(const EXRImage *image,
+                              const EXRHeader *exr_header, const char *filename,
+                              const char **err);
+
+// Saves multi-channel, single-frame OpenEXR image to a memory.
+// Image is compressed using EXRImage.compression value.
+// Return the number of bytes if success.
+// Return zero and will set error string in `err` when there's an
+// error.
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern size_t SaveEXRImageToMemory(const EXRImage *image,
+                                   const EXRHeader *exr_header,
+                                   unsigned char **memory, const char **err);
+
+// Saves multi-channel, multi-frame OpenEXR image to a memory.
+// Image is compressed using EXRImage.compression value.
+// File global attributes (eg. display_window) must be set in the first header.
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int SaveEXRMultipartImageToFile(const EXRImage *images,
+                                       const EXRHeader **exr_headers,
+                                       unsigned int num_parts,
+                                       const char *filename, const char **err);
+
+// Saves multi-channel, multi-frame OpenEXR image to a memory.
+// Image is compressed using EXRImage.compression value.
+// File global attributes (eg. display_window) must be set in the first header.
+// Return the number of bytes if success.
+// Return zero and will set error string in `err` when there's an
+// error.
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern size_t SaveEXRMultipartImageToMemory(const EXRImage *images,
+                                            const EXRHeader **exr_headers,
+                                            unsigned int num_parts,
+                                            unsigned char **memory, const char **err);
+// Loads single-frame OpenEXR deep image.
+// Application must free memory of variables in DeepImage(image, offset_table)
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int LoadDeepEXR(DeepImage *out_image, const char *filename,
+                       const char **err);
+
+// NOT YET IMPLEMENTED:
+// Saves single-frame OpenEXR deep image.
+// Returns negative value and may set error string in `err` when there's an
+// error
+// extern int SaveDeepEXR(const DeepImage *in_image, const char *filename,
+//                       const char **err);
+
+// NOT YET IMPLEMENTED:
+// Loads multi-part OpenEXR deep image.
+// Application must free memory of variables in DeepImage(image, offset_table)
+// extern int LoadMultiPartDeepEXR(DeepImage **out_image, int num_parts, const
+// char *filename,
+//                       const char **err);
+
+// For emscripten.
+// Loads single-frame OpenEXR image from memory. Assume EXR image contains
+// RGB(A) channels.
+// Returns negative value and may set error string in `err` when there's an
+// error
+// When there was an error message, Application must free `err` with
+// FreeEXRErrorMessage()
+extern int LoadEXRFromMemory(float **out_rgba, int *width, int *height,
+                             const unsigned char *memory, size_t size,
+                             const char **err);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  // TINYEXR_H_
+
+#ifdef TINYEXR_IMPLEMENTATION
+#ifndef TINYEXR_IMPLEMENTATION_DEFINED
+#define TINYEXR_IMPLEMENTATION_DEFINED
+
+#ifdef _WIN32
+
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+#ifndef NOMINMAX
+#define NOMINMAX
+#endif
+#include <windows.h>  // for UTF-8
+
+#endif
+
+#include <algorithm>
+#include <cassert>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <sstream>
+
+// #include <iostream> // debug
+
+#include <limits>
+#include <string>
+#include <vector>
+#include <set>
+
+// https://stackoverflow.com/questions/5047971/how-do-i-check-for-c11-support
+#if __cplusplus > 199711L || (defined(_MSC_VER) && _MSC_VER >= 1900)
+#define TINYEXR_HAS_CXX11 (1)
+// C++11
+#include <cstdint>
+
+#if TINYEXR_USE_THREAD
+#include <atomic>
+#include <thread>
+#endif
+
+#endif  // __cplusplus > 199711L
+
+#if TINYEXR_USE_OPENMP
+#include <omp.h>
+#endif
+
+#if TINYEXR_USE_MINIZ
+#include <miniz.h>
+#else
+//  Issue #46. Please include your own zlib-compatible API header before
+//  including `tinyexr.h`
+//#include "zlib.h"
+#endif
+
+#if TINYEXR_USE_ZFP
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Weverything"
+#endif
+
+#include "zfp.h"
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+#endif
+
+namespace tinyexr {
+
+#if __cplusplus > 199711L
+// C++11
+typedef uint64_t tinyexr_uint64;
+typedef int64_t tinyexr_int64;
+#else
+// Although `long long` is not a standard type pre C++11, assume it is defined
+// as a compiler's extension.
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wc++11-long-long"
+#endif
+typedef unsigned long long tinyexr_uint64;
+typedef long long tinyexr_int64;
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#endif
+
+// static bool IsBigEndian(void) {
+//  union {
+//    unsigned int i;
+//    char c[4];
+//  } bint = {0x01020304};
+//
+//  return bint.c[0] == 1;
+//}
+
+static void SetErrorMessage(const std::string &msg, const char **err) {
+  if (err) {
+#ifdef _WIN32
+    (*err) = _strdup(msg.c_str());
+#else
+    (*err) = strdup(msg.c_str());
+#endif
+  }
+}
+
+static void SetWarningMessage(const std::string &msg, const char **warn) {
+  if (warn) {
+#ifdef _WIN32
+    (*warn) = _strdup(msg.c_str());
+#else
+    (*warn) = strdup(msg.c_str());
+#endif
+  }
+}
+
+static const int kEXRVersionSize = 8;
+
+static void cpy2(unsigned short *dst_val, const unsigned short *src_val) {
+  unsigned char *dst = reinterpret_cast<unsigned char *>(dst_val);
+  const unsigned char *src = reinterpret_cast<const unsigned char *>(src_val);
+
+  dst[0] = src[0];
+  dst[1] = src[1];
+}
+
+static void swap2(unsigned short *val) {
+#ifdef TINYEXR_LITTLE_ENDIAN
+  (void)val;
+#else
+  unsigned short tmp = *val;
+  unsigned char *dst = reinterpret_cast<unsigned char *>(val);
+  unsigned char *src = reinterpret_cast<unsigned char *>(&tmp);
+
+  dst[0] = src[1];
+  dst[1] = src[0];
+#endif
+}
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
+
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-function"
+#endif
+static void cpy4(int *dst_val, const int *src_val) {
+  unsigned char *dst = reinterpret_cast<unsigned char *>(dst_val);
+  const unsigned char *src = reinterpret_cast<const unsigned char *>(src_val);
+
+  dst[0] = src[0];
+  dst[1] = src[1];
+  dst[2] = src[2];
+  dst[3] = src[3];
+}
+
+static void cpy4(unsigned int *dst_val, const unsigned int *src_val) {
+  unsigned char *dst = reinterpret_cast<unsigned char *>(dst_val);
+  const unsigned char *src = reinterpret_cast<const unsigned char *>(src_val);
+
+  dst[0] = src[0];
+  dst[1] = src[1];
+  dst[2] = src[2];
+  dst[3] = src[3];
+}
+
+static void cpy4(float *dst_val, const float *src_val) {
+  unsigned char *dst = reinterpret_cast<unsigned char *>(dst_val);
+  const unsigned char *src = reinterpret_cast<const unsigned char *>(src_val);
+
+  dst[0] = src[0];
+  dst[1] = src[1];
+  dst[2] = src[2];
+  dst[3] = src[3];
+}
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif
+
+static void swap4(unsigned int *val) {
+#ifdef TINYEXR_LITTLE_ENDIAN
+  (void)val;
+#else
+  unsigned int tmp = *val;
+  unsigned char *dst = reinterpret_cast<unsigned char *>(val);
+  unsigned char *src = reinterpret_cast<unsigned char *>(&tmp);
+
+  dst[0] = src[3];
+  dst[1] = src[2];
+  dst[2] = src[1];
+  dst[3] = src[0];
+#endif
+}
+
+static void swap4(int *val) {
+#ifdef TINYEXR_LITTLE_ENDIAN
+  (void)val;
+#else
+  int tmp = *val;
+  unsigned char *dst = reinterpret_cast<unsigned char *>(val);
+  unsigned char *src = reinterpret_cast<unsigned char *>(&tmp);
+
+  dst[0] = src[3];
+  dst[1] = src[2];
+  dst[2] = src[1];
+  dst[3] = src[0];
+#endif
+}
+
+static void swap4(float *val) {
+#ifdef TINYEXR_LITTLE_ENDIAN
+  (void)val;
+#else
+  float tmp = *val;
+  unsigned char *dst = reinterpret_cast<unsigned char *>(val);
+  unsigned char *src = reinterpret_cast<unsigned char *>(&tmp);
+
+  dst[0] = src[3];
+  dst[1] = src[2];
+  dst[2] = src[1];
+  dst[3] = src[0];
+#endif
+}
+
+#if 0
+static void cpy8(tinyexr::tinyexr_uint64 *dst_val, const tinyexr::tinyexr_uint64 *src_val) {
+  unsigned char *dst = reinterpret_cast<unsigned char *>(dst_val);
+  const unsigned char *src = reinterpret_cast<const unsigned char *>(src_val);
+
+  dst[0] = src[0];
+  dst[1] = src[1];
+  dst[2] = src[2];
+  dst[3] = src[3];
+  dst[4] = src[4];
+  dst[5] = src[5];
+  dst[6] = src[6];
+  dst[7] = src[7];
+}
+#endif
+
+static void swap8(tinyexr::tinyexr_uint64 *val) {
+#ifdef TINYEXR_LITTLE_ENDIAN
+  (void)val;
+#else
+  tinyexr::tinyexr_uint64 tmp = (*val);
+  unsigned char *dst = reinterpret_cast<unsigned char *>(val);
+  unsigned char *src = reinterpret_cast<unsigned char *>(&tmp);
+
+  dst[0] = src[7];
+  dst[1] = src[6];
+  dst[2] = src[5];
+  dst[3] = src[4];
+  dst[4] = src[3];
+  dst[5] = src[2];
+  dst[6] = src[1];
+  dst[7] = src[0];
+#endif
+}
+
+// https://gist.github.com/rygorous/2156668
+union FP32 {
+  unsigned int u;
+  float f;
+  struct {
+#if TINYEXR_LITTLE_ENDIAN
+    unsigned int Mantissa : 23;
+    unsigned int Exponent : 8;
+    unsigned int Sign : 1;
+#else
+    unsigned int Sign : 1;
+    unsigned int Exponent : 8;
+    unsigned int Mantissa : 23;
+#endif
+  } s;
+};
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wpadded"
+#endif
+
+union FP16 {
+  unsigned short u;
+  struct {
+#if TINYEXR_LITTLE_ENDIAN
+    unsigned int Mantissa : 10;
+    unsigned int Exponent : 5;
+    unsigned int Sign : 1;
+#else
+    unsigned int Sign : 1;
+    unsigned int Exponent : 5;
+    unsigned int Mantissa : 10;
+#endif
+  } s;
+};
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+static FP32 half_to_float(FP16 h) {
+  static const FP32 magic = {113 << 23};
+  static const unsigned int shifted_exp = 0x7c00
+                                          << 13;  // exponent mask after shift
+  FP32 o;
+
+  o.u = (h.u & 0x7fffU) << 13U;           // exponent/mantissa bits
+  unsigned int exp_ = shifted_exp & o.u;  // just the exponent
+  o.u += (127 - 15) << 23;                // exponent adjust
+
+  // handle exponent special cases
+  if (exp_ == shifted_exp)    // Inf/NaN?
+    o.u += (128 - 16) << 23;  // extra exp adjust
+  else if (exp_ == 0)         // Zero/Denormal?
+  {
+    o.u += 1 << 23;  // extra exp adjust
+    o.f -= magic.f;  // renormalize
+  }
+
+  o.u |= (h.u & 0x8000U) << 16U;  // sign bit
+  return o;
+}
+
+static FP16 float_to_half_full(FP32 f) {
+  FP16 o = {0};
+
+  // Based on ISPC reference code (with minor modifications)
+  if (f.s.Exponent == 0)  // Signed zero/denormal (which will underflow)
+    o.s.Exponent = 0;
+  else if (f.s.Exponent == 255)  // Inf or NaN (all exponent bits set)
+  {
+    o.s.Exponent = 31;
+    o.s.Mantissa = f.s.Mantissa ? 0x200 : 0;  // NaN->qNaN and Inf->Inf
+  } else                                      // Normalized number
+  {
+    // Exponent unbias the single, then bias the halfp
+    int newexp = f.s.Exponent - 127 + 15;
+    if (newexp >= 31)  // Overflow, return signed infinity
+      o.s.Exponent = 31;
+    else if (newexp <= 0)  // Underflow
+    {
+      if ((14 - newexp) <= 24)  // Mantissa might be non-zero
+      {
+        unsigned int mant = f.s.Mantissa | 0x800000;  // Hidden 1 bit
+        o.s.Mantissa = mant >> (14 - newexp);
+        if ((mant >> (13 - newexp)) & 1)  // Check for rounding
+          o.u++;  // Round, might overflow into exp bit, but this is OK
+      }
+    } else {
+      o.s.Exponent = static_cast<unsigned int>(newexp);
+      o.s.Mantissa = f.s.Mantissa >> 13;
+      if (f.s.Mantissa & 0x1000)  // Check for rounding
+        o.u++;                    // Round, might overflow to inf, this is OK
+    }
+  }
+
+  o.s.Sign = f.s.Sign;
+  return o;
+}
+
+// NOTE: From OpenEXR code
+// #define IMF_INCREASING_Y  0
+// #define IMF_DECREASING_Y  1
+// #define IMF_RAMDOM_Y    2
+//
+// #define IMF_NO_COMPRESSION  0
+// #define IMF_RLE_COMPRESSION 1
+// #define IMF_ZIPS_COMPRESSION  2
+// #define IMF_ZIP_COMPRESSION 3
+// #define IMF_PIZ_COMPRESSION 4
+// #define IMF_PXR24_COMPRESSION 5
+// #define IMF_B44_COMPRESSION 6
+// #define IMF_B44A_COMPRESSION  7
+
+#ifdef __clang__
+#pragma clang diagnostic push
+
+#if __has_warning("-Wzero-as-null-pointer-constant")
+#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant"
+#endif
+
+#endif
+
+static const char *ReadString(std::string *s, const char *ptr, size_t len) {
+  // Read untile NULL(\0).
+  const char *p = ptr;
+  const char *q = ptr;
+  while ((size_t(q - ptr) < len) && (*q) != 0) {
+    q++;
+  }
+
+  if (size_t(q - ptr) >= len) {
+    (*s).clear();
+    return NULL;
+  }
+
+  (*s) = std::string(p, q);
+
+  return q + 1;  // skip '\0'
+}
+
+static bool ReadAttribute(std::string *name, std::string *type,
+                          std::vector<unsigned char> *data, size_t *marker_size,
+                          const char *marker, size_t size) {
+  size_t name_len = strnlen(marker, size);
+  if (name_len == size) {
+    // String does not have a terminating character.
+    return false;
+  }
+  *name = std::string(marker, name_len);
+
+  marker += name_len + 1;
+  size -= name_len + 1;
+
+  size_t type_len = strnlen(marker, size);
+  if (type_len == size) {
+    return false;
+  }
+  *type = std::string(marker, type_len);
+
+  marker += type_len + 1;
+  size -= type_len + 1;
+
+  if (size < sizeof(uint32_t)) {
+    return false;
+  }
+
+  uint32_t data_len;
+  memcpy(&data_len, marker, sizeof(uint32_t));
+  tinyexr::swap4(reinterpret_cast<unsigned int *>(&data_len));
+
+  if (data_len == 0) {
+    if ((*type).compare("string") == 0) {
+      // Accept empty string attribute.
+
+      marker += sizeof(uint32_t);
+      size -= sizeof(uint32_t);
+
+      *marker_size = name_len + 1 + type_len + 1 + sizeof(uint32_t);
+
+      data->resize(1);
+      (*data)[0] = '\0';
+
+      return true;
+    } else {
+      return false;
+    }
+  }
+
+  marker += sizeof(uint32_t);
+  size -= sizeof(uint32_t);
+
+  if (size < data_len) {
+    return false;
+  }
+
+  data->resize(static_cast<size_t>(data_len));
+  memcpy(&data->at(0), marker, static_cast<size_t>(data_len));
+
+  *marker_size = name_len + 1 + type_len + 1 + sizeof(uint32_t) + data_len;
+  return true;
+}
+
+static void WriteAttributeToMemory(std::vector<unsigned char> *out,
+                                   const char *name, const char *type,
+                                   const unsigned char *data, int len) {
+  out->insert(out->end(), name, name + strlen(name) + 1);
+  out->insert(out->end(), type, type + strlen(type) + 1);
+
+  int outLen = len;
+  tinyexr::swap4(&outLen);
+  out->insert(out->end(), reinterpret_cast<unsigned char *>(&outLen),
+              reinterpret_cast<unsigned char *>(&outLen) + sizeof(int));
+  out->insert(out->end(), data, data + len);
+}
+
+typedef struct {
+  std::string name;  // less than 255 bytes long
+  int pixel_type;
+  int requested_pixel_type;
+  int x_sampling;
+  int y_sampling;
+  unsigned char p_linear;
+  unsigned char pad[3];
+} ChannelInfo;
+
+typedef struct {
+  int min_x;
+  int min_y;
+  int max_x;
+  int max_y;
+} Box2iInfo;
+
+struct HeaderInfo {
+  std::vector<tinyexr::ChannelInfo> channels;
+  std::vector<EXRAttribute> attributes;
+
+  Box2iInfo data_window;
+  int line_order;
+  Box2iInfo display_window;
+  float screen_window_center[2];
+  float screen_window_width;
+  float pixel_aspect_ratio;
+
+  int chunk_count;
+
+  // Tiled format
+  int tiled; // Non-zero if the part is tiled.
+  int tile_size_x;
+  int tile_size_y;
+  int tile_level_mode;
+  int tile_rounding_mode;
+
+  unsigned int header_len;
+
+  int compression_type;
+
+  // required for multi-part or non-image files
+  std::string name;
+  // required for multi-part or non-image files
+  std::string type;
+
+  void clear() {
+    channels.clear();
+    attributes.clear();
+
+    data_window.min_x = 0;
+    data_window.min_y = 0;
+    data_window.max_x = 0;
+    data_window.max_y = 0;
+    line_order = 0;
+    display_window.min_x = 0;
+    display_window.min_y = 0;
+    display_window.max_x = 0;
+    display_window.max_y = 0;
+    screen_window_center[0] = 0.0f;
+    screen_window_center[1] = 0.0f;
+    screen_window_width = 0.0f;
+    pixel_aspect_ratio = 0.0f;
+
+    chunk_count = 0;
+
+    // Tiled format
+    tiled = 0;
+    tile_size_x = 0;
+    tile_size_y = 0;
+    tile_level_mode = 0;
+    tile_rounding_mode = 0;
+
+    header_len = 0;
+    compression_type = 0;
+
+    name.clear();
+    type.clear();
+  }
+};
+
+static bool ReadChannelInfo(std::vector<ChannelInfo> &channels,
+                            const std::vector<unsigned char> &data) {
+  const char *p = reinterpret_cast<const char *>(&data.at(0));
+
+  for (;;) {
+    if ((*p) == 0) {
+      break;
+    }
+    ChannelInfo info;
+
+    tinyexr_int64 data_len = static_cast<tinyexr_int64>(data.size()) -
+                             (p - reinterpret_cast<const char *>(data.data()));
+    if (data_len < 0) {
+      return false;
+    }
+
+    p = ReadString(&info.name, p, size_t(data_len));
+    if ((p == NULL) && (info.name.empty())) {
+      // Buffer overrun. Issue #51.
+      return false;
+    }
+
+    const unsigned char *data_end =
+        reinterpret_cast<const unsigned char *>(p) + 16;
+    if (data_end >= (data.data() + data.size())) {
+      return false;
+    }
+
+    memcpy(&info.pixel_type, p, sizeof(int));
+    p += 4;
+    info.p_linear = static_cast<unsigned char>(p[0]);  // uchar
+    p += 1 + 3;                                        // reserved: uchar[3]
+    memcpy(&info.x_sampling, p, sizeof(int));          // int
+    p += 4;
+    memcpy(&info.y_sampling, p, sizeof(int));  // int
+    p += 4;
+
+    tinyexr::swap4(&info.pixel_type);
+    tinyexr::swap4(&info.x_sampling);
+    tinyexr::swap4(&info.y_sampling);
+
+    channels.push_back(info);
+  }
+
+  return true;
+}
+
+static void WriteChannelInfo(std::vector<unsigned char> &data,
+                             const std::vector<ChannelInfo> &channels) {
+  size_t sz = 0;
+
+  // Calculate total size.
+  for (size_t c = 0; c < channels.size(); c++) {
+    sz += channels[c].name.length() + 1;  // +1 for \0
+    sz += 16;                                    // 4 * int
+  }
+  data.resize(sz + 1);
+
+  unsigned char *p = &data.at(0);
+
+  for (size_t c = 0; c < channels.size(); c++) {
+    memcpy(p, channels[c].name.c_str(), channels[c].name.length());
+    p += channels[c].name.length();
+    (*p) = '\0';
+    p++;
+
+    int pixel_type = channels[c].requested_pixel_type;
+    int x_sampling = channels[c].x_sampling;
+    int y_sampling = channels[c].y_sampling;
+    tinyexr::swap4(&pixel_type);
+    tinyexr::swap4(&x_sampling);
+    tinyexr::swap4(&y_sampling);
+
+    memcpy(p, &pixel_type, sizeof(int));
+    p += sizeof(int);
+
+    (*p) = channels[c].p_linear;
+    p += 4;
+
+    memcpy(p, &x_sampling, sizeof(int));
+    p += sizeof(int);
+
+    memcpy(p, &y_sampling, sizeof(int));
+    p += sizeof(int);
+  }
+
+  (*p) = '\0';
+}
+
+static void CompressZip(unsigned char *dst,
+                        tinyexr::tinyexr_uint64 &compressedSize,
+                        const unsigned char *src, unsigned long src_size) {
+  std::vector<unsigned char> tmpBuf(src_size);
+
+  //
+  // Apply EXR-specific? postprocess. Grabbed from OpenEXR's
+  // ImfZipCompressor.cpp
+  //
+
+  //
+  // Reorder the pixel data.
+  //
+
+  const char *srcPtr = reinterpret_cast<const char *>(src);
+
+  {
+    char *t1 = reinterpret_cast<char *>(&tmpBuf.at(0));
+    char *t2 = reinterpret_cast<char *>(&tmpBuf.at(0)) + (src_size + 1) / 2;
+    const char *stop = srcPtr + src_size;
+
+    for (;;) {
+      if (srcPtr < stop)
+        *(t1++) = *(srcPtr++);
+      else
+        break;
+
+      if (srcPtr < stop)
+        *(t2++) = *(srcPtr++);
+      else
+        break;
+    }
+  }
+
+  //
+  // Predictor.
+  //
+
+  {
+    unsigned char *t = &tmpBuf.at(0) + 1;
+    unsigned char *stop = &tmpBuf.at(0) + src_size;
+    int p = t[-1];
+
+    while (t < stop) {
+      int d = int(t[0]) - p + (128 + 256);
+      p = t[0];
+      t[0] = static_cast<unsigned char>(d);
+      ++t;
+    }
+  }
+
+#if TINYEXR_USE_MINIZ
+  //
+  // Compress the data using miniz
+  //
+
+  mz_ulong outSize = mz_compressBound(src_size);
+  int ret = mz_compress(
+      dst, &outSize, static_cast<const unsigned char *>(&tmpBuf.at(0)),
+      src_size);
+  assert(ret == MZ_OK);
+  (void)ret;
+
+  compressedSize = outSize;
+#else
+  uLong outSize = compressBound(static_cast<uLong>(src_size));
+  int ret = compress(dst, &outSize, static_cast<const Bytef *>(&tmpBuf.at(0)),
+                     src_size);
+  assert(ret == Z_OK);
+
+  compressedSize = outSize;
+#endif
+
+  // Use uncompressed data when compressed data is larger than uncompressed.
+  // (Issue 40)
+  if (compressedSize >= src_size) {
+    compressedSize = src_size;
+    memcpy(dst, src, src_size);
+  }
+}
+
+static bool DecompressZip(unsigned char *dst,
+                          unsigned long *uncompressed_size /* inout */,
+                          const unsigned char *src, unsigned long src_size) {
+  if ((*uncompressed_size) == src_size) {
+    // Data is not compressed(Issue 40).
+    memcpy(dst, src, src_size);
+    return true;
+  }
+  std::vector<unsigned char> tmpBuf(*uncompressed_size);
+
+#if TINYEXR_USE_MINIZ
+  int ret =
+      mz_uncompress(&tmpBuf.at(0), uncompressed_size, src, src_size);
+  if (MZ_OK != ret) {
+    return false;
+  }
+#else
+  int ret = uncompress(&tmpBuf.at(0), uncompressed_size, src, src_size);
+  if (Z_OK != ret) {
+    return false;
+  }
+#endif
+
+  //
+  // Apply EXR-specific? postprocess. Grabbed from OpenEXR's
+  // ImfZipCompressor.cpp
+  //
+
+  // Predictor.
+  {
+    unsigned char *t = &tmpBuf.at(0) + 1;
+    unsigned char *stop = &tmpBuf.at(0) + (*uncompressed_size);
+
+    while (t < stop) {
+      int d = int(t[-1]) + int(t[0]) - 128;
+      t[0] = static_cast<unsigned char>(d);
+      ++t;
+    }
+  }
+
+  // Reorder the pixel data.
+  {
+    const char *t1 = reinterpret_cast<const char *>(&tmpBuf.at(0));
+    const char *t2 = reinterpret_cast<const char *>(&tmpBuf.at(0)) +
+                     (*uncompressed_size + 1) / 2;
+    char *s = reinterpret_cast<char *>(dst);
+    char *stop = s + (*uncompressed_size);
+
+    for (;;) {
+      if (s < stop)
+        *(s++) = *(t1++);
+      else
+        break;
+
+      if (s < stop)
+        *(s++) = *(t2++);
+      else
+        break;
+    }
+  }
+
+  return true;
+}
+
+// RLE code from OpenEXR --------------------------------------
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wsign-conversion"
+#if __has_warning("-Wextra-semi-stmt")
+#pragma clang diagnostic ignored "-Wextra-semi-stmt"
+#endif
+#endif
+
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 4204)  // nonstandard extension used : non-constant
+                                 // aggregate initializer (also supported by GNU
+                                 // C and C99, so no big deal)
+#pragma warning(disable : 4244)  // 'initializing': conversion from '__int64' to
+                                 // 'int', possible loss of data
+#pragma warning(disable : 4267)  // 'argument': conversion from '__int64' to
+                                 // 'int', possible loss of data
+#pragma warning(disable : 4996)  // 'strdup': The POSIX name for this item is
+                                 // deprecated. Instead, use the ISO C and C++
+                                 // conformant name: _strdup.
+#endif
+
+const int MIN_RUN_LENGTH = 3;
+const int MAX_RUN_LENGTH = 127;
+
+//
+// Compress an array of bytes, using run-length encoding,
+// and return the length of the compressed data.
+//
+
+static int rleCompress(int inLength, const char in[], signed char out[]) {
+  const char *inEnd = in + inLength;
+  const char *runStart = in;
+  const char *runEnd = in + 1;
+  signed char *outWrite = out;
+
+  while (runStart < inEnd) {
+    while (runEnd < inEnd && *runStart == *runEnd &&
+           runEnd - runStart - 1 < MAX_RUN_LENGTH) {
+      ++runEnd;
+    }
+
+    if (runEnd - runStart >= MIN_RUN_LENGTH) {
+      //
+      // Compressible run
+      //
+
+      *outWrite++ = static_cast<char>(runEnd - runStart) - 1;
+      *outWrite++ = *(reinterpret_cast<const signed char *>(runStart));
+      runStart = runEnd;
+    } else {
+      //
+      // Uncompressable run
+      //
+
+      while (runEnd < inEnd &&
+             ((runEnd + 1 >= inEnd || *runEnd != *(runEnd + 1)) ||
+              (runEnd + 2 >= inEnd || *(runEnd + 1) != *(runEnd + 2))) &&
+             runEnd - runStart < MAX_RUN_LENGTH) {
+        ++runEnd;
+      }
+
+      *outWrite++ = static_cast<char>(runStart - runEnd);
+
+      while (runStart < runEnd) {
+        *outWrite++ = *(reinterpret_cast<const signed char *>(runStart++));
+      }
+    }
+
+    ++runEnd;
+  }
+
+  return static_cast<int>(outWrite - out);
+}
+
+//
+// Uncompress an array of bytes compressed with rleCompress().
+// Returns the length of the oncompressed data, or 0 if the
+// length of the uncompressed data would be more than maxLength.
+//
+
+static int rleUncompress(int inLength, int maxLength, const signed char in[],
+                         char out[]) {
+  char *outStart = out;
+
+  while (inLength > 0) {
+    if (*in < 0) {
+      int count = -(static_cast<int>(*in++));
+      inLength -= count + 1;
+
+      // Fixes #116: Add bounds check to in buffer.
+      if ((0 > (maxLength -= count)) || (inLength < 0)) return 0;
+
+      memcpy(out, in, count);
+      out += count;
+      in += count;
+    } else {
+      int count = *in++;
+      inLength -= 2;
+
+      if (0 > (maxLength -= count + 1)) return 0;
+
+      memset(out, *reinterpret_cast<const char *>(in), count + 1);
+      out += count + 1;
+
+      in++;
+    }
+  }
+
+  return static_cast<int>(out - outStart);
+}
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+// End of RLE code from OpenEXR -----------------------------------
+
+static void CompressRle(unsigned char *dst,
+                        tinyexr::tinyexr_uint64 &compressedSize,
+                        const unsigned char *src, unsigned long src_size) {
+  std::vector<unsigned char> tmpBuf(src_size);
+
+  //
+  // Apply EXR-specific? postprocess. Grabbed from OpenEXR's
+  // ImfRleCompressor.cpp
+  //
+
+  //
+  // Reorder the pixel data.
+  //
+
+  const char *srcPtr = reinterpret_cast<const char *>(src);
+
+  {
+    char *t1 = reinterpret_cast<char *>(&tmpBuf.at(0));
+    char *t2 = reinterpret_cast<char *>(&tmpBuf.at(0)) + (src_size + 1) / 2;
+    const char *stop = srcPtr + src_size;
+
+    for (;;) {
+      if (srcPtr < stop)
+        *(t1++) = *(srcPtr++);
+      else
+        break;
+
+      if (srcPtr < stop)
+        *(t2++) = *(srcPtr++);
+      else
+        break;
+    }
+  }
+
+  //
+  // Predictor.
+  //
+
+  {
+    unsigned char *t = &tmpBuf.at(0) + 1;
+    unsigned char *stop = &tmpBuf.at(0) + src_size;
+    int p = t[-1];
+
+    while (t < stop) {
+      int d = int(t[0]) - p + (128 + 256);
+      p = t[0];
+      t[0] = static_cast<unsigned char>(d);
+      ++t;
+    }
+  }
+
+  // outSize will be (srcSiz * 3) / 2 at max.
+  int outSize = rleCompress(static_cast<int>(src_size),
+                            reinterpret_cast<const char *>(&tmpBuf.at(0)),
+                            reinterpret_cast<signed char *>(dst));
+  assert(outSize > 0);
+
+  compressedSize = static_cast<tinyexr::tinyexr_uint64>(outSize);
+
+  // Use uncompressed data when compressed data is larger than uncompressed.
+  // (Issue 40)
+  if (compressedSize >= src_size) {
+    compressedSize = src_size;
+    memcpy(dst, src, src_size);
+  }
+}
+
+static bool DecompressRle(unsigned char *dst,
+                          const unsigned long uncompressed_size,
+                          const unsigned char *src, unsigned long src_size) {
+  if (uncompressed_size == src_size) {
+    // Data is not compressed(Issue 40).
+    memcpy(dst, src, src_size);
+    return true;
+  }
+
+  // Workaround for issue #112.
+  // TODO(syoyo): Add more robust out-of-bounds check in `rleUncompress`.
+  if (src_size <= 2) {
+    return false;
+  }
+
+  std::vector<unsigned char> tmpBuf(uncompressed_size);
+
+  int ret = rleUncompress(static_cast<int>(src_size),
+                          static_cast<int>(uncompressed_size),
+                          reinterpret_cast<const signed char *>(src),
+                          reinterpret_cast<char *>(&tmpBuf.at(0)));
+  if (ret != static_cast<int>(uncompressed_size)) {
+    return false;
+  }
+
+  //
+  // Apply EXR-specific? postprocess. Grabbed from OpenEXR's
+  // ImfRleCompressor.cpp
+  //
+
+  // Predictor.
+  {
+    unsigned char *t = &tmpBuf.at(0) + 1;
+    unsigned char *stop = &tmpBuf.at(0) + uncompressed_size;
+
+    while (t < stop) {
+      int d = int(t[-1]) + int(t[0]) - 128;
+      t[0] = static_cast<unsigned char>(d);
+      ++t;
+    }
+  }
+
+  // Reorder the pixel data.
+  {
+    const char *t1 = reinterpret_cast<const char *>(&tmpBuf.at(0));
+    const char *t2 = reinterpret_cast<const char *>(&tmpBuf.at(0)) +
+                     (uncompressed_size + 1) / 2;
+    char *s = reinterpret_cast<char *>(dst);
+    char *stop = s + uncompressed_size;
+
+    for (;;) {
+      if (s < stop)
+        *(s++) = *(t1++);
+      else
+        break;
+
+      if (s < stop)
+        *(s++) = *(t2++);
+      else
+        break;
+    }
+  }
+
+  return true;
+}
+
+#if TINYEXR_USE_PIZ
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wc++11-long-long"
+#pragma clang diagnostic ignored "-Wold-style-cast"
+#pragma clang diagnostic ignored "-Wpadded"
+#pragma clang diagnostic ignored "-Wsign-conversion"
+#pragma clang diagnostic ignored "-Wc++11-extensions"
+#pragma clang diagnostic ignored "-Wconversion"
+#pragma clang diagnostic ignored "-Wc++98-compat-pedantic"
+
+#if __has_warning("-Wcast-qual")
+#pragma clang diagnostic ignored "-Wcast-qual"
+#endif
+
+#if __has_warning("-Wextra-semi-stmt")
+#pragma clang diagnostic ignored "-Wextra-semi-stmt"
+#endif
+
+#endif
+
+//
+// PIZ compress/uncompress, based on OpenEXR's ImfPizCompressor.cpp
+//
+// -----------------------------------------------------------------
+// Copyright (c) 2004, Industrial Light & Magic, a division of Lucas
+// Digital Ltd. LLC)
+// (3 clause BSD license)
+//
+
+struct PIZChannelData {
+  unsigned short *start;
+  unsigned short *end;
+  int nx;
+  int ny;
+  int ys;
+  int size;
+};
+
+//-----------------------------------------------------------------------------
+//
+//  16-bit Haar Wavelet encoding and decoding
+//
+//  The source code in this file is derived from the encoding
+//  and decoding routines written by Christian Rouet for his
+//  PIZ image file format.
+//
+//-----------------------------------------------------------------------------
+
+//
+// Wavelet basis functions without modulo arithmetic; they produce
+// the best compression ratios when the wavelet-transformed data are
+// Huffman-encoded, but the wavelet transform works only for 14-bit
+// data (untransformed data values must be less than (1 << 14)).
+//
+
+inline void wenc14(unsigned short a, unsigned short b, unsigned short &l,
+                   unsigned short &h) {
+  short as = static_cast<short>(a);
+  short bs = static_cast<short>(b);
+
+  short ms = (as + bs) >> 1;
+  short ds = as - bs;
+
+  l = static_cast<unsigned short>(ms);
+  h = static_cast<unsigned short>(ds);
+}
+
+inline void wdec14(unsigned short l, unsigned short h, unsigned short &a,
+                   unsigned short &b) {
+  short ls = static_cast<short>(l);
+  short hs = static_cast<short>(h);
+
+  int hi = hs;
+  int ai = ls + (hi & 1) + (hi >> 1);
+
+  short as = static_cast<short>(ai);
+  short bs = static_cast<short>(ai - hi);
+
+  a = static_cast<unsigned short>(as);
+  b = static_cast<unsigned short>(bs);
+}
+
+//
+// Wavelet basis functions with modulo arithmetic; they work with full
+// 16-bit data, but Huffman-encoding the wavelet-transformed data doesn't
+// compress the data quite as well.
+//
+
+const int NBITS = 16;
+const int A_OFFSET = 1 << (NBITS - 1);
+const int M_OFFSET = 1 << (NBITS - 1);
+const int MOD_MASK = (1 << NBITS) - 1;
+
+inline void wenc16(unsigned short a, unsigned short b, unsigned short &l,
+                   unsigned short &h) {
+  int ao = (a + A_OFFSET) & MOD_MASK;
+  int m = ((ao + b) >> 1);
+  int d = ao - b;
+
+  if (d < 0) m = (m + M_OFFSET) & MOD_MASK;
+
+  d &= MOD_MASK;
+
+  l = static_cast<unsigned short>(m);
+  h = static_cast<unsigned short>(d);
+}
+
+inline void wdec16(unsigned short l, unsigned short h, unsigned short &a,
+                   unsigned short &b) {
+  int m = l;
+  int d = h;
+  int bb = (m - (d >> 1)) & MOD_MASK;
+  int aa = (d + bb - A_OFFSET) & MOD_MASK;
+  b = static_cast<unsigned short>(bb);
+  a = static_cast<unsigned short>(aa);
+}
+
+//
+// 2D Wavelet encoding:
+//
+
+static void wav2Encode(
+    unsigned short *in,  // io: values are transformed in place
+    int nx,              // i : x size
+    int ox,              // i : x offset
+    int ny,              // i : y size
+    int oy,              // i : y offset
+    unsigned short mx)   // i : maximum in[x][y] value
+{
+  bool w14 = (mx < (1 << 14));
+  int n = (nx > ny) ? ny : nx;
+  int p = 1;   // == 1 <<  level
+  int p2 = 2;  // == 1 << (level+1)
+
+  //
+  // Hierarchical loop on smaller dimension n
+  //
+
+  while (p2 <= n) {
+    unsigned short *py = in;
+    unsigned short *ey = in + oy * (ny - p2);
+    int oy1 = oy * p;
+    int oy2 = oy * p2;
+    int ox1 = ox * p;
+    int ox2 = ox * p2;
+    unsigned short i00, i01, i10, i11;
+
+    //
+    // Y loop
+    //
+
+    for (; py <= ey; py += oy2) {
+      unsigned short *px = py;
+      unsigned short *ex = py + ox * (nx - p2);
+
+      //
+      // X loop
+      //
+
+      for (; px <= ex; px += ox2) {
+        unsigned short *p01 = px + ox1;
+        unsigned short *p10 = px + oy1;
+        unsigned short *p11 = p10 + ox1;
+
+        //
+        // 2D wavelet encoding
+        //
+
+        if (w14) {
+          wenc14(*px, *p01, i00, i01);
+          wenc14(*p10, *p11, i10, i11);
+          wenc14(i00, i10, *px, *p10);
+          wenc14(i01, i11, *p01, *p11);
+        } else {
+          wenc16(*px, *p01, i00, i01);
+          wenc16(*p10, *p11, i10, i11);
+          wenc16(i00, i10, *px, *p10);
+          wenc16(i01, i11, *p01, *p11);
+        }
+      }
+
+      //
+      // Encode (1D) odd column (still in Y loop)
+      //
+
+      if (nx & p) {
+        unsigned short *p10 = px + oy1;
+
+        if (w14)
+          wenc14(*px, *p10, i00, *p10);
+        else
+          wenc16(*px, *p10, i00, *p10);
+
+        *px = i00;
+      }
+    }
+
+    //
+    // Encode (1D) odd line (must loop in X)
+    //
+
+    if (ny & p) {
+      unsigned short *px = py;
+      unsigned short *ex = py + ox * (nx - p2);
+
+      for (; px <= ex; px += ox2) {
+        unsigned short *p01 = px + ox1;
+
+        if (w14)
+          wenc14(*px, *p01, i00, *p01);
+        else
+          wenc16(*px, *p01, i00, *p01);
+
+        *px = i00;
+      }
+    }
+
+    //
+    // Next level
+    //
+
+    p = p2;
+    p2 <<= 1;
+  }
+}
+
+//
+// 2D Wavelet decoding:
+//
+
+static void wav2Decode(
+    unsigned short *in,  // io: values are transformed in place
+    int nx,              // i : x size
+    int ox,              // i : x offset
+    int ny,              // i : y size
+    int oy,              // i : y offset
+    unsigned short mx)   // i : maximum in[x][y] value
+{
+  bool w14 = (mx < (1 << 14));
+  int n = (nx > ny) ? ny : nx;
+  int p = 1;
+  int p2;
+
+  //
+  // Search max level
+  //
+
+  while (p <= n) p <<= 1;
+
+  p >>= 1;
+  p2 = p;
+  p >>= 1;
+
+  //
+  // Hierarchical loop on smaller dimension n
+  //
+
+  while (p >= 1) {
+    unsigned short *py = in;
+    unsigned short *ey = in + oy * (ny - p2);
+    int oy1 = oy * p;
+    int oy2 = oy * p2;
+    int ox1 = ox * p;
+    int ox2 = ox * p2;
+    unsigned short i00, i01, i10, i11;
+
+    //
+    // Y loop
+    //
+
+    for (; py <= ey; py += oy2) {
+      unsigned short *px = py;
+      unsigned short *ex = py + ox * (nx - p2);
+
+      //
+      // X loop
+      //
+
+      for (; px <= ex; px += ox2) {
+        unsigned short *p01 = px + ox1;
+        unsigned short *p10 = px + oy1;
+        unsigned short *p11 = p10 + ox1;
+
+        //
+        // 2D wavelet decoding
+        //
+
+        if (w14) {
+          wdec14(*px, *p10, i00, i10);
+          wdec14(*p01, *p11, i01, i11);
+          wdec14(i00, i01, *px, *p01);
+          wdec14(i10, i11, *p10, *p11);
+        } else {
+          wdec16(*px, *p10, i00, i10);
+          wdec16(*p01, *p11, i01, i11);
+          wdec16(i00, i01, *px, *p01);
+          wdec16(i10, i11, *p10, *p11);
+        }
+      }
+
+      //
+      // Decode (1D) odd column (still in Y loop)
+      //
+
+      if (nx & p) {
+        unsigned short *p10 = px + oy1;
+
+        if (w14)
+          wdec14(*px, *p10, i00, *p10);
+        else
+          wdec16(*px, *p10, i00, *p10);
+
+        *px = i00;
+      }
+    }
+
+    //
+    // Decode (1D) odd line (must loop in X)
+    //
+
+    if (ny & p) {
+      unsigned short *px = py;
+      unsigned short *ex = py + ox * (nx - p2);
+
+      for (; px <= ex; px += ox2) {
+        unsigned short *p01 = px + ox1;
+
+        if (w14)
+          wdec14(*px, *p01, i00, *p01);
+        else
+          wdec16(*px, *p01, i00, *p01);
+
+        *px = i00;
+      }
+    }
+
+    //
+    // Next level
+    //
+
+    p2 = p;
+    p >>= 1;
+  }
+}
+
+//-----------------------------------------------------------------------------
+//
+//  16-bit Huffman compression and decompression.
+//
+//  The source code in this file is derived from the 8-bit
+//  Huffman compression and decompression routines written
+//  by Christian Rouet for his PIZ image file format.
+//
+//-----------------------------------------------------------------------------
+
+// Adds some modification for tinyexr.
+
+const int HUF_ENCBITS = 16;  // literal (value) bit length
+const int HUF_DECBITS = 14;  // decoding bit size (>= 8)
+
+const int HUF_ENCSIZE = (1 << HUF_ENCBITS) + 1;  // encoding table size
+const int HUF_DECSIZE = 1 << HUF_DECBITS;        // decoding table size
+const int HUF_DECMASK = HUF_DECSIZE - 1;
+
+struct HufDec {  // short code    long code
+  //-------------------------------
+  unsigned int len : 8;   // code length    0
+  unsigned int lit : 24;  // lit      p size
+  unsigned int *p;        // 0      lits
+};
+
+inline long long hufLength(long long code) { return code & 63; }
+
+inline long long hufCode(long long code) { return code >> 6; }
+
+inline void outputBits(int nBits, long long bits, long long &c, int &lc,
+                       char *&out) {
+  c <<= nBits;
+  lc += nBits;
+
+  c |= bits;
+
+  while (lc >= 8) *out++ = static_cast<char>((c >> (lc -= 8)));
+}
+
+inline long long getBits(int nBits, long long &c, int &lc, const char *&in) {
+  while (lc < nBits) {
+    c = (c << 8) | *(reinterpret_cast<const unsigned char *>(in++));
+    lc += 8;
+  }
+
+  lc -= nBits;
+  return (c >> lc) & ((1 << nBits) - 1);
+}
+
+//
+// ENCODING TABLE BUILDING & (UN)PACKING
+//
+
+//
+// Build a "canonical" Huffman code table:
+//  - for each (uncompressed) symbol, hcode contains the length
+//    of the corresponding code (in the compressed data)
+//  - canonical codes are computed and stored in hcode
+//  - the rules for constructing canonical codes are as follows:
+//    * shorter codes (if filled with zeroes to the right)
+//      have a numerically higher value than longer codes
+//    * for codes with the same length, numerical values
+//      increase with numerical symbol values
+//  - because the canonical code table can be constructed from
+//    symbol lengths alone, the code table can be transmitted
+//    without sending the actual code values
+//  - see http://www.compressconsult.com/huffman/
+//
+
+static void hufCanonicalCodeTable(long long hcode[HUF_ENCSIZE]) {
+  long long n[59];
+
+  //
+  // For each i from 0 through 58, count the
+  // number of different codes of length i, and
+  // store the count in n[i].
+  //
+
+  for (int i = 0; i <= 58; ++i) n[i] = 0;
+
+  for (int i = 0; i < HUF_ENCSIZE; ++i) n[hcode[i]] += 1;
+
+  //
+  // For each i from 58 through 1, compute the
+  // numerically lowest code with length i, and
+  // store that code in n[i].
+  //
+
+  long long c = 0;
+
+  for (int i = 58; i > 0; --i) {
+    long long nc = ((c + n[i]) >> 1);
+    n[i] = c;
+    c = nc;
+  }
+
+  //
+  // hcode[i] contains the length, l, of the
+  // code for symbol i.  Assign the next available
+  // code of length l to the symbol and store both
+  // l and the code in hcode[i].
+  //
+
+  for (int i = 0; i < HUF_ENCSIZE; ++i) {
+    int l = static_cast<int>(hcode[i]);
+
+    if (l > 0) hcode[i] = l | (n[l]++ << 6);
+  }
+}
+
+//
+// Compute Huffman codes (based on frq input) and store them in frq:
+//  - code structure is : [63:lsb - 6:msb] | [5-0: bit length];
+//  - max code length is 58 bits;
+//  - codes outside the range [im-iM] have a null length (unused values);
+//  - original frequencies are destroyed;
+//  - encoding tables are used by hufEncode() and hufBuildDecTable();
+//
+
+struct FHeapCompare {
+  bool operator()(long long *a, long long *b) { return *a > *b; }
+};
+
+static void hufBuildEncTable(
+    long long *frq,  // io: input frequencies [HUF_ENCSIZE], output table
+    int *im,         //  o: min frq index
+    int *iM)         //  o: max frq index
+{
+  //
+  // This function assumes that when it is called, array frq
+  // indicates the frequency of all possible symbols in the data
+  // that are to be Huffman-encoded.  (frq[i] contains the number
+  // of occurrences of symbol i in the data.)
+  //
+  // The loop below does three things:
+  //
+  // 1) Finds the minimum and maximum indices that point
+  //    to non-zero entries in frq:
+  //
+  //     frq[im] != 0, and frq[i] == 0 for all i < im
+  //     frq[iM] != 0, and frq[i] == 0 for all i > iM
+  //
+  // 2) Fills array fHeap with pointers to all non-zero
+  //    entries in frq.
+  //
+  // 3) Initializes array hlink such that hlink[i] == i
+  //    for all array entries.
+  //
+
+  std::vector<int> hlink(HUF_ENCSIZE);
+  std::vector<long long *> fHeap(HUF_ENCSIZE);
+
+  *im = 0;
+
+  while (!frq[*im]) (*im)++;
+
+  int nf = 0;
+
+  for (int i = *im; i < HUF_ENCSIZE; i++) {
+    hlink[i] = i;
+
+    if (frq[i]) {
+      fHeap[nf] = &frq[i];
+      nf++;
+      *iM = i;
+    }
+  }
+
+  //
+  // Add a pseudo-symbol, with a frequency count of 1, to frq;
+  // adjust the fHeap and hlink array accordingly.  Function
+  // hufEncode() uses the pseudo-symbol for run-length encoding.
+  //
+
+  (*iM)++;
+  frq[*iM] = 1;
+  fHeap[nf] = &frq[*iM];
+  nf++;
+
+  //
+  // Build an array, scode, such that scode[i] contains the number
+  // of bits assigned to symbol i.  Conceptually this is done by
+  // constructing a tree whose leaves are the symbols with non-zero
+  // frequency:
+  //
+  //     Make a heap that contains all symbols with a non-zero frequency,
+  //     with the least frequent symbol on top.
+  //
+  //     Repeat until only one symbol is left on the heap:
+  //
+  //         Take the two least frequent symbols off the top of the heap.
+  //         Create a new node that has first two nodes as children, and
+  //         whose frequency is the sum of the frequencies of the first
+  //         two nodes.  Put the new node back into the heap.
+  //
+  // The last node left on the heap is the root of the tree.  For each
+  // leaf node, the distance between the root and the leaf is the length
+  // of the code for the corresponding symbol.
+  //
+  // The loop below doesn't actually build the tree; instead we compute
+  // the distances of the leaves from the root on the fly.  When a new
+  // node is added to the heap, then that node's descendants are linked
+  // into a single linear list that starts at the new node, and the code
+  // lengths of the descendants (that is, their distance from the root
+  // of the tree) are incremented by one.
+  //
+
+  std::make_heap(&fHeap[0], &fHeap[nf], FHeapCompare());
+
+  std::vector<long long> scode(HUF_ENCSIZE);
+  memset(scode.data(), 0, sizeof(long long) * HUF_ENCSIZE);
+
+  while (nf > 1) {
+    //
+    // Find the indices, mm and m, of the two smallest non-zero frq
+    // values in fHeap, add the smallest frq to the second-smallest
+    // frq, and remove the smallest frq value from fHeap.
+    //
+
+    int mm = fHeap[0] - frq;
+    std::pop_heap(&fHeap[0], &fHeap[nf], FHeapCompare());
+    --nf;
+
+    int m = fHeap[0] - frq;
+    std::pop_heap(&fHeap[0], &fHeap[nf], FHeapCompare());
+
+    frq[m] += frq[mm];
+    std::push_heap(&fHeap[0], &fHeap[nf], FHeapCompare());
+
+    //
+    // The entries in scode are linked into lists with the
+    // entries in hlink serving as "next" pointers and with
+    // the end of a list marked by hlink[j] == j.
+    //
+    // Traverse the lists that start at scode[m] and scode[mm].
+    // For each element visited, increment the length of the
+    // corresponding code by one bit. (If we visit scode[j]
+    // during the traversal, then the code for symbol j becomes
+    // one bit longer.)
+    //
+    // Merge the lists that start at scode[m] and scode[mm]
+    // into a single list that starts at scode[m].
+    //
+
+    //
+    // Add a bit to all codes in the first list.
+    //
+
+    for (int j = m;; j = hlink[j]) {
+      scode[j]++;
+
+      assert(scode[j] <= 58);
+
+      if (hlink[j] == j) {
+        //
+        // Merge the two lists.
+        //
+
+        hlink[j] = mm;
+        break;
+      }
+    }
+
+    //
+    // Add a bit to all codes in the second list
+    //
+
+    for (int j = mm;; j = hlink[j]) {
+      scode[j]++;
+
+      assert(scode[j] <= 58);
+
+      if (hlink[j] == j) break;
+    }
+  }
+
+  //
+  // Build a canonical Huffman code table, replacing the code
+  // lengths in scode with (code, code length) pairs.  Copy the
+  // code table from scode into frq.
+  //
+
+  hufCanonicalCodeTable(scode.data());
+  memcpy(frq, scode.data(), sizeof(long long) * HUF_ENCSIZE);
+}
+
+//
+// Pack an encoding table:
+//  - only code lengths, not actual codes, are stored
+//  - runs of zeroes are compressed as follows:
+//
+//    unpacked    packed
+//    --------------------------------
+//    1 zero    0  (6 bits)
+//    2 zeroes    59
+//    3 zeroes    60
+//    4 zeroes    61
+//    5 zeroes    62
+//    n zeroes (6 or more)  63 n-6  (6 + 8 bits)
+//
+
+const int SHORT_ZEROCODE_RUN = 59;
+const int LONG_ZEROCODE_RUN = 63;
+const int SHORTEST_LONG_RUN = 2 + LONG_ZEROCODE_RUN - SHORT_ZEROCODE_RUN;
+const int LONGEST_LONG_RUN = 255 + SHORTEST_LONG_RUN;
+
+static void hufPackEncTable(
+    const long long *hcode,  // i : encoding table [HUF_ENCSIZE]
+    int im,                  // i : min hcode index
+    int iM,                  // i : max hcode index
+    char **pcode)            //  o: ptr to packed table (updated)
+{
+  char *p = *pcode;
+  long long c = 0;
+  int lc = 0;
+
+  for (; im <= iM; im++) {
+    int l = hufLength(hcode[im]);
+
+    if (l == 0) {
+      int zerun = 1;
+
+      while ((im < iM) && (zerun < LONGEST_LONG_RUN)) {
+        if (hufLength(hcode[im + 1]) > 0) break;
+        im++;
+        zerun++;
+      }
+
+      if (zerun >= 2) {
+        if (zerun >= SHORTEST_LONG_RUN) {
+          outputBits(6, LONG_ZEROCODE_RUN, c, lc, p);
+          outputBits(8, zerun - SHORTEST_LONG_RUN, c, lc, p);
+        } else {
+          outputBits(6, SHORT_ZEROCODE_RUN + zerun - 2, c, lc, p);
+        }
+        continue;
+      }
+    }
+
+    outputBits(6, l, c, lc, p);
+  }
+
+  if (lc > 0) *p++ = (unsigned char)(c << (8 - lc));
+
+  *pcode = p;
+}
+
+//
+// Unpack an encoding table packed by hufPackEncTable():
+//
+
+static bool hufUnpackEncTable(
+    const char **pcode,  // io: ptr to packed table (updated)
+    int ni,              // i : input size (in bytes)
+    int im,              // i : min hcode index
+    int iM,              // i : max hcode index
+    long long *hcode)    //  o: encoding table [HUF_ENCSIZE]
+{
+  memset(hcode, 0, sizeof(long long) * HUF_ENCSIZE);
+
+  const char *p = *pcode;
+  long long c = 0;
+  int lc = 0;
+
+  for (; im <= iM; im++) {
+    if (p - *pcode >= ni) {
+      return false;
+    }
+
+    long long l = hcode[im] = getBits(6, c, lc, p);  // code length
+
+    if (l == (long long)LONG_ZEROCODE_RUN) {
+      if (p - *pcode > ni) {
+        return false;
+      }
+
+      int zerun = getBits(8, c, lc, p) + SHORTEST_LONG_RUN;
+
+      if (im + zerun > iM + 1) {
+        return false;
+      }
+
+      while (zerun--) hcode[im++] = 0;
+
+      im--;
+    } else if (l >= (long long)SHORT_ZEROCODE_RUN) {
+      int zerun = l - SHORT_ZEROCODE_RUN + 2;
+
+      if (im + zerun > iM + 1) {
+        return false;
+      }
+
+      while (zerun--) hcode[im++] = 0;
+
+      im--;
+    }
+  }
+
+  *pcode = const_cast<char *>(p);
+
+  hufCanonicalCodeTable(hcode);
+
+  return true;
+}
+
+//
+// DECODING TABLE BUILDING
+//
+
+//
+// Clear a newly allocated decoding table so that it contains only zeroes.
+//
+
+static void hufClearDecTable(HufDec *hdecod)  // io: (allocated by caller)
+//     decoding table [HUF_DECSIZE]
+{
+  for (int i = 0; i < HUF_DECSIZE; i++) {
+    hdecod[i].len = 0;
+    hdecod[i].lit = 0;
+    hdecod[i].p = NULL;
+  }
+  // memset(hdecod, 0, sizeof(HufDec) * HUF_DECSIZE);
+}
+
+//
+// Build a decoding hash table based on the encoding table hcode:
+//  - short codes (<= HUF_DECBITS) are resolved with a single table access;
+//  - long code entry allocations are not optimized, because long codes are
+//    unfrequent;
+//  - decoding tables are used by hufDecode();
+//
+
+static bool hufBuildDecTable(const long long *hcode,  // i : encoding table
+                             int im,                  // i : min index in hcode
+                             int iM,                  // i : max index in hcode
+                             HufDec *hdecod)  //  o: (allocated by caller)
+//     decoding table [HUF_DECSIZE]
+{
+  //
+  // Init hashtable & loop on all codes.
+  // Assumes that hufClearDecTable(hdecod) has already been called.
+  //
+
+  for (; im <= iM; im++) {
+    long long c = hufCode(hcode[im]);
+    int l = hufLength(hcode[im]);
+
+    if (c >> l) {
+      //
+      // Error: c is supposed to be an l-bit code,
+      // but c contains a value that is greater
+      // than the largest l-bit number.
+      //
+
+      // invalidTableEntry();
+      return false;
+    }
+
+    if (l > HUF_DECBITS) {
+      //
+      // Long code: add a secondary entry
+      //
+
+      HufDec *pl = hdecod + (c >> (l - HUF_DECBITS));
+
+      if (pl->len) {
+        //
+        // Error: a short code has already
+        // been stored in table entry *pl.
+        //
+
+        // invalidTableEntry();
+        return false;
+      }
+
+      pl->lit++;
+
+      if (pl->p) {
+        unsigned int *p = pl->p;
+        pl->p = new unsigned int[pl->lit];
+
+        for (int i = 0; i < pl->lit - 1; ++i) pl->p[i] = p[i];
+
+        delete[] p;
+      } else {
+        pl->p = new unsigned int[1];
+      }
+
+      pl->p[pl->lit - 1] = im;
+    } else if (l) {
+      //
+      // Short code: init all primary entries
+      //
+
+      HufDec *pl = hdecod + (c << (HUF_DECBITS - l));
+
+      for (long long i = 1ULL << (HUF_DECBITS - l); i > 0; i--, pl++) {
+        if (pl->len || pl->p) {
+          //
+          // Error: a short code or a long code has
+          // already been stored in table entry *pl.
+          //
+
+          // invalidTableEntry();
+          return false;
+        }
+
+        pl->len = l;
+        pl->lit = im;
+      }
+    }
+  }
+
+  return true;
+}
+
+//
+// Free the long code entries of a decoding table built by hufBuildDecTable()
+//
+
+static void hufFreeDecTable(HufDec *hdecod)  // io: Decoding table
+{
+  for (int i = 0; i < HUF_DECSIZE; i++) {
+    if (hdecod[i].p) {
+      delete[] hdecod[i].p;
+      hdecod[i].p = 0;
+    }
+  }
+}
+
+//
+// ENCODING
+//
+
+inline void outputCode(long long code, long long &c, int &lc, char *&out) {
+  outputBits(hufLength(code), hufCode(code), c, lc, out);
+}
+
+inline void sendCode(long long sCode, int runCount, long long runCode,
+                     long long &c, int &lc, char *&out) {
+  //
+  // Output a run of runCount instances of the symbol sCount.
+  // Output the symbols explicitly, or if that is shorter, output
+  // the sCode symbol once followed by a runCode symbol and runCount
+  // expressed as an 8-bit number.
+  //
+
+  if (hufLength(sCode) + hufLength(runCode) + 8 < hufLength(sCode) * runCount) {
+    outputCode(sCode, c, lc, out);
+    outputCode(runCode, c, lc, out);
+    outputBits(8, runCount, c, lc, out);
+  } else {
+    while (runCount-- >= 0) outputCode(sCode, c, lc, out);
+  }
+}
+
+//
+// Encode (compress) ni values based on the Huffman encoding table hcode:
+//
+
+static int hufEncode            // return: output size (in bits)
+    (const long long *hcode,    // i : encoding table
+     const unsigned short *in,  // i : uncompressed input buffer
+     const int ni,              // i : input buffer size (in bytes)
+     int rlc,                   // i : rl code
+     char *out)                 //  o: compressed output buffer
+{
+  char *outStart = out;
+  long long c = 0;  // bits not yet written to out
+  int lc = 0;       // number of valid bits in c (LSB)
+  int s = in[0];
+  int cs = 0;
+
+  //
+  // Loop on input values
+  //
+
+  for (int i = 1; i < ni; i++) {
+    //
+    // Count same values or send code
+    //
+
+    if (s == in[i] && cs < 255) {
+      cs++;
+    } else {
+      sendCode(hcode[s], cs, hcode[rlc], c, lc, out);
+      cs = 0;
+    }
+
+    s = in[i];
+  }
+
+  //
+  // Send remaining code
+  //
+
+  sendCode(hcode[s], cs, hcode[rlc], c, lc, out);
+
+  if (lc) *out = (c << (8 - lc)) & 0xff;
+
+  return (out - outStart) * 8 + lc;
+}
+
+//
+// DECODING
+//
+
+//
+// In order to force the compiler to inline them,
+// getChar() and getCode() are implemented as macros
+// instead of "inline" functions.
+//
+
+#define getChar(c, lc, in)                   \
+  {                                          \
+    c = (c << 8) | *(unsigned char *)(in++); \
+    lc += 8;                                 \
+  }
+
+#if 0
+#define getCode(po, rlc, c, lc, in, out, ob, oe) \
+  {                                              \
+    if (po == rlc) {                             \
+      if (lc < 8) getChar(c, lc, in);            \
+                                                 \
+      lc -= 8;                                   \
+                                                 \
+      unsigned char cs = (c >> lc);              \
+                                                 \
+      if (out + cs > oe) return false;           \
+                                                 \
+      /* TinyEXR issue 78 */                     \
+      unsigned short s = out[-1];                \
+                                                 \
+      while (cs-- > 0) *out++ = s;               \
+    } else if (out < oe) {                       \
+      *out++ = po;                               \
+    } else {                                     \
+      return false;                              \
+    }                                            \
+  }
+#else
+static bool getCode(int po, int rlc, long long &c, int &lc, const char *&in,
+                    const char *in_end, unsigned short *&out,
+                    const unsigned short *ob, const unsigned short *oe) {
+  (void)ob;
+  if (po == rlc) {
+    if (lc < 8) {
+      /* TinyEXR issue 78 */
+      /* TinyEXR issue 160. in + 1 -> in */
+      if (in >= in_end) {
+        return false;
+      }
+
+      getChar(c, lc, in);
+    }
+
+    lc -= 8;
+
+    unsigned char cs = (c >> lc);
+
+    if (out + cs > oe) return false;
+
+    // Bounds check for safety
+    // Issue 100.
+    if ((out - 1) < ob) return false;
+    unsigned short s = out[-1];
+
+    while (cs-- > 0) *out++ = s;
+  } else if (out < oe) {
+    *out++ = po;
+  } else {
+    return false;
+  }
+  return true;
+}
+#endif
+
+//
+// Decode (uncompress) ni bits based on encoding & decoding tables:
+//
+
+static bool hufDecode(const long long *hcode,  // i : encoding table
+                      const HufDec *hdecod,    // i : decoding table
+                      const char *in,          // i : compressed input buffer
+                      int ni,                  // i : input size (in bits)
+                      int rlc,                 // i : run-length code
+                      int no,  // i : expected output size (in bytes)
+                      unsigned short *out)  //  o: uncompressed output buffer
+{
+  long long c = 0;
+  int lc = 0;
+  unsigned short *outb = out;          // begin
+  unsigned short *oe = out + no;       // end
+  const char *ie = in + (ni + 7) / 8;  // input byte size
+
+  //
+  // Loop on input bytes
+  //
+
+  while (in < ie) {
+    getChar(c, lc, in);
+
+    //
+    // Access decoding table
+    //
+
+    while (lc >= HUF_DECBITS) {
+      const HufDec pl = hdecod[(c >> (lc - HUF_DECBITS)) & HUF_DECMASK];
+
+      if (pl.len) {
+        //
+        // Get short code
+        //
+
+        lc -= pl.len;
+        // std::cout << "lit = " << pl.lit << std::endl;
+        // std::cout << "rlc = " << rlc << std::endl;
+        // std::cout << "c = " << c << std::endl;
+        // std::cout << "lc = " << lc << std::endl;
+        // std::cout << "in = " << in << std::endl;
+        // std::cout << "out = " << out << std::endl;
+        // std::cout << "oe = " << oe << std::endl;
+        if (!getCode(pl.lit, rlc, c, lc, in, ie, out, outb, oe)) {
+          return false;
+        }
+      } else {
+        if (!pl.p) {
+          return false;
+        }
+        // invalidCode(); // wrong code
+
+        //
+        // Search long code
+        //
+
+        int j;
+
+        for (j = 0; j < pl.lit; j++) {
+          int l = hufLength(hcode[pl.p[j]]);
+
+          while (lc < l && in < ie)  // get more bits
+            getChar(c, lc, in);
+
+          if (lc >= l) {
+            if (hufCode(hcode[pl.p[j]]) ==
+                ((c >> (lc - l)) & (((long long)(1) << l) - 1))) {
+              //
+              // Found : get long code
+              //
+
+              lc -= l;
+              if (!getCode(pl.p[j], rlc, c, lc, in, ie, out, outb, oe)) {
+                return false;
+              }
+              break;
+            }
+          }
+        }
+
+        if (j == pl.lit) {
+          return false;
+          // invalidCode(); // Not found
+        }
+      }
+    }
+  }
+
+  //
+  // Get remaining (short) codes
+  //
+
+  int i = (8 - ni) & 7;
+  c >>= i;
+  lc -= i;
+
+  while (lc > 0) {
+    const HufDec pl = hdecod[(c << (HUF_DECBITS - lc)) & HUF_DECMASK];
+
+    if (pl.len) {
+      lc -= pl.len;
+      if (!getCode(pl.lit, rlc, c, lc, in, ie, out, outb, oe)) {
+        return false;
+      }
+    } else {
+      return false;
+      // invalidCode(); // wrong (long) code
+    }
+  }
+
+  if (out - outb != no) {
+    return false;
+  }
+  // notEnoughData ();
+
+  return true;
+}
+
+static void countFrequencies(std::vector<long long> &freq,
+                             const unsigned short data[/*n*/], int n) {
+  for (int i = 0; i < HUF_ENCSIZE; ++i) freq[i] = 0;
+
+  for (int i = 0; i < n; ++i) ++freq[data[i]];
+}
+
+static void writeUInt(char buf[4], unsigned int i) {
+  unsigned char *b = (unsigned char *)buf;
+
+  b[0] = i;
+  b[1] = i >> 8;
+  b[2] = i >> 16;
+  b[3] = i >> 24;
+}
+
+static unsigned int readUInt(const char buf[4]) {
+  const unsigned char *b = (const unsigned char *)buf;
+
+  return (b[0] & 0x000000ff) | ((b[1] << 8) & 0x0000ff00) |
+         ((b[2] << 16) & 0x00ff0000) | ((b[3] << 24) & 0xff000000);
+}
+
+//
+// EXTERNAL INTERFACE
+//
+
+static int hufCompress(const unsigned short raw[], int nRaw,
+                       char compressed[]) {
+  if (nRaw == 0) return 0;
+
+  std::vector<long long> freq(HUF_ENCSIZE);
+
+  countFrequencies(freq, raw, nRaw);
+
+  int im = 0;
+  int iM = 0;
+  hufBuildEncTable(freq.data(), &im, &iM);
+
+  char *tableStart = compressed + 20;
+  char *tableEnd = tableStart;
+  hufPackEncTable(freq.data(), im, iM, &tableEnd);
+  int tableLength = tableEnd - tableStart;
+
+  char *dataStart = tableEnd;
+  int nBits = hufEncode(freq.data(), raw, nRaw, iM, dataStart);
+  int data_length = (nBits + 7) / 8;
+
+  writeUInt(compressed, im);
+  writeUInt(compressed + 4, iM);
+  writeUInt(compressed + 8, tableLength);
+  writeUInt(compressed + 12, nBits);
+  writeUInt(compressed + 16, 0);  // room for future extensions
+
+  return dataStart + data_length - compressed;
+}
+
+static bool hufUncompress(const char compressed[], int nCompressed,
+                          std::vector<unsigned short> *raw) {
+  if (nCompressed == 0) {
+    if (raw->size() != 0) return false;
+
+    return false;
+  }
+
+  int im = readUInt(compressed);
+  int iM = readUInt(compressed + 4);
+  // int tableLength = readUInt (compressed + 8);
+  int nBits = readUInt(compressed + 12);
+
+  if (im < 0 || im >= HUF_ENCSIZE || iM < 0 || iM >= HUF_ENCSIZE) return false;
+
+  const char *ptr = compressed + 20;
+
+  //
+  // Fast decoder needs at least 2x64-bits of compressed data, and
+  // needs to be run-able on this platform. Otherwise, fall back
+  // to the original decoder
+  //
+
+  // if (FastHufDecoder::enabled() && nBits > 128)
+  //{
+  //    FastHufDecoder fhd (ptr, nCompressed - (ptr - compressed), im, iM, iM);
+  //    fhd.decode ((unsigned char*)ptr, nBits, raw, nRaw);
+  //}
+  // else
+  {
+    std::vector<long long> freq(HUF_ENCSIZE);
+    std::vector<HufDec> hdec(HUF_DECSIZE);
+
+    hufClearDecTable(&hdec.at(0));
+
+    hufUnpackEncTable(&ptr, nCompressed - (ptr - compressed), im, iM,
+                      &freq.at(0));
+
+    {
+      if (nBits > 8 * (nCompressed - (ptr - compressed))) {
+        return false;
+      }
+
+      hufBuildDecTable(&freq.at(0), im, iM, &hdec.at(0));
+      hufDecode(&freq.at(0), &hdec.at(0), ptr, nBits, iM, raw->size(),
+                raw->data());
+    }
+    // catch (...)
+    //{
+    //    hufFreeDecTable (hdec);
+    //    throw;
+    //}
+
+    hufFreeDecTable(&hdec.at(0));
+  }
+
+  return true;
+}
+
+//
+// Functions to compress the range of values in the pixel data
+//
+
+const int USHORT_RANGE = (1 << 16);
+const int BITMAP_SIZE = (USHORT_RANGE >> 3);
+
+static void bitmapFromData(const unsigned short data[/*nData*/], int nData,
+                           unsigned char bitmap[BITMAP_SIZE],
+                           unsigned short &minNonZero,
+                           unsigned short &maxNonZero) {
+  for (int i = 0; i < BITMAP_SIZE; ++i) bitmap[i] = 0;
+
+  for (int i = 0; i < nData; ++i) bitmap[data[i] >> 3] |= (1 << (data[i] & 7));
+
+  bitmap[0] &= ~1;  // zero is not explicitly stored in
+                    // the bitmap; we assume that the
+                    // data always contain zeroes
+  minNonZero = BITMAP_SIZE - 1;
+  maxNonZero = 0;
+
+  for (int i = 0; i < BITMAP_SIZE; ++i) {
+    if (bitmap[i]) {
+      if (minNonZero > i) minNonZero = i;
+      if (maxNonZero < i) maxNonZero = i;
+    }
+  }
+}
+
+static unsigned short forwardLutFromBitmap(
+    const unsigned char bitmap[BITMAP_SIZE], unsigned short lut[USHORT_RANGE]) {
+  int k = 0;
+
+  for (int i = 0; i < USHORT_RANGE; ++i) {
+    if ((i == 0) || (bitmap[i >> 3] & (1 << (i & 7))))
+      lut[i] = k++;
+    else
+      lut[i] = 0;
+  }
+
+  return k - 1;  // maximum value stored in lut[],
+}  // i.e. number of ones in bitmap minus 1
+
+static unsigned short reverseLutFromBitmap(
+    const unsigned char bitmap[BITMAP_SIZE], unsigned short lut[USHORT_RANGE]) {
+  int k = 0;
+
+  for (int i = 0; i < USHORT_RANGE; ++i) {
+    if ((i == 0) || (bitmap[i >> 3] & (1 << (i & 7)))) lut[k++] = i;
+  }
+
+  int n = k - 1;
+
+  while (k < USHORT_RANGE) lut[k++] = 0;
+
+  return n;  // maximum k where lut[k] is non-zero,
+}  // i.e. number of ones in bitmap minus 1
+
+static void applyLut(const unsigned short lut[USHORT_RANGE],
+                     unsigned short data[/*nData*/], int nData) {
+  for (int i = 0; i < nData; ++i) data[i] = lut[data[i]];
+}
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif  // __clang__
+
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
+static bool CompressPiz(unsigned char *outPtr, unsigned int *outSize,
+                        const unsigned char *inPtr, size_t inSize,
+                        const std::vector<ChannelInfo> &channelInfo,
+                        int data_width, int num_lines) {
+  std::vector<unsigned char> bitmap(BITMAP_SIZE);
+  unsigned short minNonZero;
+  unsigned short maxNonZero;
+
+#if !TINYEXR_LITTLE_ENDIAN
+  // @todo { PIZ compression on BigEndian architecture. }
+  assert(0);
+  return false;
+#endif
+
+  // Assume `inSize` is multiple of 2 or 4.
+  std::vector<unsigned short> tmpBuffer(inSize / sizeof(unsigned short));
+
+  std::vector<PIZChannelData> channelData(channelInfo.size());
+  unsigned short *tmpBufferEnd = &tmpBuffer.at(0);
+
+  for (size_t c = 0; c < channelData.size(); c++) {
+    PIZChannelData &cd = channelData[c];
+
+    cd.start = tmpBufferEnd;
+    cd.end = cd.start;
+
+    cd.nx = data_width;
+    cd.ny = num_lines;
+    // cd.ys = c.channel().ySampling;
+
+    size_t pixelSize = sizeof(int);  // UINT and FLOAT
+    if (channelInfo[c].requested_pixel_type == TINYEXR_PIXELTYPE_HALF) {
+      pixelSize = sizeof(short);
+    }
+
+    cd.size = static_cast<int>(pixelSize / sizeof(short));
+
+    tmpBufferEnd += cd.nx * cd.ny * cd.size;
+  }
+
+  const unsigned char *ptr = inPtr;
+  for (int y = 0; y < num_lines; ++y) {
+    for (size_t i = 0; i < channelData.size(); ++i) {
+      PIZChannelData &cd = channelData[i];
+
+      // if (modp (y, cd.ys) != 0)
+      //    continue;
+
+      size_t n = static_cast<size_t>(cd.nx * cd.size);
+      memcpy(cd.end, ptr, n * sizeof(unsigned short));
+      ptr += n * sizeof(unsigned short);
+      cd.end += n;
+    }
+  }
+
+  bitmapFromData(&tmpBuffer.at(0), static_cast<int>(tmpBuffer.size()),
+                 bitmap.data(), minNonZero, maxNonZero);
+
+  std::vector<unsigned short> lut(USHORT_RANGE);
+  unsigned short maxValue = forwardLutFromBitmap(bitmap.data(), lut.data());
+  applyLut(lut.data(), &tmpBuffer.at(0), static_cast<int>(tmpBuffer.size()));
+
+  //
+  // Store range compression info in _outBuffer
+  //
+
+  char *buf = reinterpret_cast<char *>(outPtr);
+
+  memcpy(buf, &minNonZero, sizeof(unsigned short));
+  buf += sizeof(unsigned short);
+  memcpy(buf, &maxNonZero, sizeof(unsigned short));
+  buf += sizeof(unsigned short);
+
+  if (minNonZero <= maxNonZero) {
+    memcpy(buf, reinterpret_cast<char *>(&bitmap[0] + minNonZero),
+           maxNonZero - minNonZero + 1);
+    buf += maxNonZero - minNonZero + 1;
+  }
+
+  //
+  // Apply wavelet encoding
+  //
+
+  for (size_t i = 0; i < channelData.size(); ++i) {
+    PIZChannelData &cd = channelData[i];
+
+    for (int j = 0; j < cd.size; ++j) {
+      wav2Encode(cd.start + j, cd.nx, cd.size, cd.ny, cd.nx * cd.size,
+                 maxValue);
+    }
+  }
+
+  //
+  // Apply Huffman encoding; append the result to _outBuffer
+  //
+
+  // length header(4byte), then huff data. Initialize length header with zero,
+  // then later fill it by `length`.
+  char *lengthPtr = buf;
+  int zero = 0;
+  memcpy(buf, &zero, sizeof(int));
+  buf += sizeof(int);
+
+  int length =
+      hufCompress(&tmpBuffer.at(0), static_cast<int>(tmpBuffer.size()), buf);
+  memcpy(lengthPtr, &length, sizeof(int));
+
+  (*outSize) = static_cast<unsigned int>(
+      (reinterpret_cast<unsigned char *>(buf) - outPtr) +
+      static_cast<unsigned int>(length));
+
+  // Use uncompressed data when compressed data is larger than uncompressed.
+  // (Issue 40)
+  if ((*outSize) >= inSize) {
+    (*outSize) = static_cast<unsigned int>(inSize);
+    memcpy(outPtr, inPtr, inSize);
+  }
+  return true;
+}
+
+static bool DecompressPiz(unsigned char *outPtr, const unsigned char *inPtr,
+                          size_t tmpBufSizeInBytes, size_t inLen, int num_channels,
+                          const EXRChannelInfo *channels, int data_width,
+                          int num_lines) {
+  if (inLen == tmpBufSizeInBytes) {
+    // Data is not compressed(Issue 40).
+    memcpy(outPtr, inPtr, inLen);
+    return true;
+  }
+
+  std::vector<unsigned char> bitmap(BITMAP_SIZE);
+  unsigned short minNonZero;
+  unsigned short maxNonZero;
+
+#if !TINYEXR_LITTLE_ENDIAN
+  // @todo { PIZ compression on BigEndian architecture. }
+  assert(0);
+  return false;
+#endif
+
+  memset(bitmap.data(), 0, BITMAP_SIZE);
+
+  const unsigned char *ptr = inPtr;
+  // minNonZero = *(reinterpret_cast<const unsigned short *>(ptr));
+  tinyexr::cpy2(&minNonZero, reinterpret_cast<const unsigned short *>(ptr));
+  // maxNonZero = *(reinterpret_cast<const unsigned short *>(ptr + 2));
+  tinyexr::cpy2(&maxNonZero, reinterpret_cast<const unsigned short *>(ptr + 2));
+  ptr += 4;
+
+  if (maxNonZero >= BITMAP_SIZE) {
+    return false;
+  }
+
+  if (minNonZero <= maxNonZero) {
+    memcpy(reinterpret_cast<char *>(&bitmap[0] + minNonZero), ptr,
+           maxNonZero - minNonZero + 1);
+    ptr += maxNonZero - minNonZero + 1;
+  }
+
+  std::vector<unsigned short> lut(USHORT_RANGE);
+  memset(lut.data(), 0, sizeof(unsigned short) * USHORT_RANGE);
+  unsigned short maxValue = reverseLutFromBitmap(bitmap.data(), lut.data());
+
+  //
+  // Huffman decoding
+  //
+
+  int length;
+
+  // length = *(reinterpret_cast<const int *>(ptr));
+  tinyexr::cpy4(&length, reinterpret_cast<const int *>(ptr));
+  ptr += sizeof(int);
+
+  if (size_t((ptr - inPtr) + length) > inLen) {
+    return false;
+  }
+
+  std::vector<unsigned short> tmpBuffer(tmpBufSizeInBytes / sizeof(unsigned short));
+  hufUncompress(reinterpret_cast<const char *>(ptr), length, &tmpBuffer);
+
+  //
+  // Wavelet decoding
+  //
+
+  std::vector<PIZChannelData> channelData(static_cast<size_t>(num_channels));
+
+  unsigned short *tmpBufferEnd = &tmpBuffer.at(0);
+
+  for (size_t i = 0; i < static_cast<size_t>(num_channels); ++i) {
+    const EXRChannelInfo &chan = channels[i];
+
+    size_t pixelSize = sizeof(int);  // UINT and FLOAT
+    if (chan.pixel_type == TINYEXR_PIXELTYPE_HALF) {
+      pixelSize = sizeof(short);
+    }
+
+    channelData[i].start = tmpBufferEnd;
+    channelData[i].end = channelData[i].start;
+    channelData[i].nx = data_width;
+    channelData[i].ny = num_lines;
+    // channelData[i].ys = 1;
+    channelData[i].size = static_cast<int>(pixelSize / sizeof(short));
+
+    tmpBufferEnd += channelData[i].nx * channelData[i].ny * channelData[i].size;
+  }
+
+  for (size_t i = 0; i < channelData.size(); ++i) {
+    PIZChannelData &cd = channelData[i];
+
+    for (int j = 0; j < cd.size; ++j) {
+      wav2Decode(cd.start + j, cd.nx, cd.size, cd.ny, cd.nx * cd.size,
+                 maxValue);
+    }
+  }
+
+  //
+  // Expand the pixel data to their original range
+  //
+
+  applyLut(lut.data(), &tmpBuffer.at(0), static_cast<int>(tmpBufSizeInBytes / sizeof(unsigned short)));
+
+  for (int y = 0; y < num_lines; y++) {
+    for (size_t i = 0; i < channelData.size(); ++i) {
+      PIZChannelData &cd = channelData[i];
+
+      // if (modp (y, cd.ys) != 0)
+      //    continue;
+
+      size_t n = static_cast<size_t>(cd.nx * cd.size);
+      memcpy(outPtr, cd.end, static_cast<size_t>(n * sizeof(unsigned short)));
+      outPtr += n * sizeof(unsigned short);
+      cd.end += n;
+    }
+  }
+
+  return true;
+}
+#endif  // TINYEXR_USE_PIZ
+
+#if TINYEXR_USE_ZFP
+
+struct ZFPCompressionParam {
+  double rate;
+  unsigned int precision;
+  unsigned int __pad0;
+  double tolerance;
+  int type;  // TINYEXR_ZFP_COMPRESSIONTYPE_*
+  unsigned int __pad1;
+
+  ZFPCompressionParam() {
+    type = TINYEXR_ZFP_COMPRESSIONTYPE_RATE;
+    rate = 2.0;
+    precision = 0;
+    tolerance = 0.0;
+  }
+};
+
+static bool FindZFPCompressionParam(ZFPCompressionParam *param,
+                                    const EXRAttribute *attributes,
+                                    int num_attributes, std::string *err) {
+  bool foundType = false;
+
+  for (int i = 0; i < num_attributes; i++) {
+    if ((strcmp(attributes[i].name, "zfpCompressionType") == 0)) {
+      if (attributes[i].size == 1) {
+        param->type = static_cast<int>(attributes[i].value[0]);
+        foundType = true;
+        break;
+      } else {
+        if (err) {
+          (*err) +=
+              "zfpCompressionType attribute must be uchar(1 byte) type.\n";
+        }
+        return false;
+      }
+    }
+  }
+
+  if (!foundType) {
+    if (err) {
+      (*err) += "`zfpCompressionType` attribute not found.\n";
+    }
+    return false;
+  }
+
+  if (param->type == TINYEXR_ZFP_COMPRESSIONTYPE_RATE) {
+    for (int i = 0; i < num_attributes; i++) {
+      if ((strcmp(attributes[i].name, "zfpCompressionRate") == 0) &&
+          (attributes[i].size == 8)) {
+        param->rate = *(reinterpret_cast<double *>(attributes[i].value));
+        return true;
+      }
+    }
+
+    if (err) {
+      (*err) += "`zfpCompressionRate` attribute not found.\n";
+    }
+
+  } else if (param->type == TINYEXR_ZFP_COMPRESSIONTYPE_PRECISION) {
+    for (int i = 0; i < num_attributes; i++) {
+      if ((strcmp(attributes[i].name, "zfpCompressionPrecision") == 0) &&
+          (attributes[i].size == 4)) {
+        param->rate = *(reinterpret_cast<int *>(attributes[i].value));
+        return true;
+      }
+    }
+
+    if (err) {
+      (*err) += "`zfpCompressionPrecision` attribute not found.\n";
+    }
+
+  } else if (param->type == TINYEXR_ZFP_COMPRESSIONTYPE_ACCURACY) {
+    for (int i = 0; i < num_attributes; i++) {
+      if ((strcmp(attributes[i].name, "zfpCompressionTolerance") == 0) &&
+          (attributes[i].size == 8)) {
+        param->tolerance = *(reinterpret_cast<double *>(attributes[i].value));
+        return true;
+      }
+    }
+
+    if (err) {
+      (*err) += "`zfpCompressionTolerance` attribute not found.\n";
+    }
+  } else {
+    if (err) {
+      (*err) += "Unknown value specified for `zfpCompressionType`.\n";
+    }
+  }
+
+  return false;
+}
+
+// Assume pixel format is FLOAT for all channels.
+static bool DecompressZfp(float *dst, int dst_width, int dst_num_lines,
+                          size_t num_channels, const unsigned char *src,
+                          unsigned long src_size,
+                          const ZFPCompressionParam &param) {
+  size_t uncompressed_size =
+      size_t(dst_width) * size_t(dst_num_lines) * num_channels;
+
+  if (uncompressed_size == src_size) {
+    // Data is not compressed(Issue 40).
+    memcpy(dst, src, src_size);
+  }
+
+  zfp_stream *zfp = NULL;
+  zfp_field *field = NULL;
+
+  assert((dst_width % 4) == 0);
+  assert((dst_num_lines % 4) == 0);
+
+  if ((size_t(dst_width) & 3U) || (size_t(dst_num_lines) & 3U)) {
+    return false;
+  }
+
+  field =
+      zfp_field_2d(reinterpret_cast<void *>(const_cast<unsigned char *>(src)),
+                   zfp_type_float, static_cast<unsigned int>(dst_width),
+                   static_cast<unsigned int>(dst_num_lines) *
+                       static_cast<unsigned int>(num_channels));
+  zfp = zfp_stream_open(NULL);
+
+  if (param.type == TINYEXR_ZFP_COMPRESSIONTYPE_RATE) {
+    zfp_stream_set_rate(zfp, param.rate, zfp_type_float, /* dimension */ 2,
+                        /* write random access */ 0);
+  } else if (param.type == TINYEXR_ZFP_COMPRESSIONTYPE_PRECISION) {
+    zfp_stream_set_precision(zfp, param.precision);
+  } else if (param.type == TINYEXR_ZFP_COMPRESSIONTYPE_ACCURACY) {
+    zfp_stream_set_accuracy(zfp, param.tolerance);
+  } else {
+    assert(0);
+  }
+
+  size_t buf_size = zfp_stream_maximum_size(zfp, field);
+  std::vector<unsigned char> buf(buf_size);
+  memcpy(&buf.at(0), src, src_size);
+
+  bitstream *stream = stream_open(&buf.at(0), buf_size);
+  zfp_stream_set_bit_stream(zfp, stream);
+  zfp_stream_rewind(zfp);
+
+  size_t image_size = size_t(dst_width) * size_t(dst_num_lines);
+
+  for (size_t c = 0; c < size_t(num_channels); c++) {
+    // decompress 4x4 pixel block.
+    for (size_t y = 0; y < size_t(dst_num_lines); y += 4) {
+      for (size_t x = 0; x < size_t(dst_width); x += 4) {
+        float fblock[16];
+        zfp_decode_block_float_2(zfp, fblock);
+        for (size_t j = 0; j < 4; j++) {
+          for (size_t i = 0; i < 4; i++) {
+            dst[c * image_size + ((y + j) * size_t(dst_width) + (x + i))] =
+                fblock[j * 4 + i];
+          }
+        }
+      }
+    }
+  }
+
+  zfp_field_free(field);
+  zfp_stream_close(zfp);
+  stream_close(stream);
+
+  return true;
+}
+
+// Assume pixel format is FLOAT for all channels.
+static bool CompressZfp(std::vector<unsigned char> *outBuf,
+                        unsigned int *outSize, const float *inPtr, int width,
+                        int num_lines, int num_channels,
+                        const ZFPCompressionParam &param) {
+  zfp_stream *zfp = NULL;
+  zfp_field *field = NULL;
+
+  assert((width % 4) == 0);
+  assert((num_lines % 4) == 0);
+
+  if ((size_t(width) & 3U) || (size_t(num_lines) & 3U)) {
+    return false;
+  }
+
+  // create input array.
+  field = zfp_field_2d(reinterpret_cast<void *>(const_cast<float *>(inPtr)),
+                       zfp_type_float, static_cast<unsigned int>(width),
+                       static_cast<unsigned int>(num_lines * num_channels));
+
+  zfp = zfp_stream_open(NULL);
+
+  if (param.type == TINYEXR_ZFP_COMPRESSIONTYPE_RATE) {
+    zfp_stream_set_rate(zfp, param.rate, zfp_type_float, 2, 0);
+  } else if (param.type == TINYEXR_ZFP_COMPRESSIONTYPE_PRECISION) {
+    zfp_stream_set_precision(zfp, param.precision);
+  } else if (param.type == TINYEXR_ZFP_COMPRESSIONTYPE_ACCURACY) {
+    zfp_stream_set_accuracy(zfp, param.tolerance);
+  } else {
+    assert(0);
+  }
+
+  size_t buf_size = zfp_stream_maximum_size(zfp, field);
+
+  outBuf->resize(buf_size);
+
+  bitstream *stream = stream_open(&outBuf->at(0), buf_size);
+  zfp_stream_set_bit_stream(zfp, stream);
+  zfp_field_free(field);
+
+  size_t image_size = size_t(width) * size_t(num_lines);
+
+  for (size_t c = 0; c < size_t(num_channels); c++) {
+    // compress 4x4 pixel block.
+    for (size_t y = 0; y < size_t(num_lines); y += 4) {
+      for (size_t x = 0; x < size_t(width); x += 4) {
+        float fblock[16];
+        for (size_t j = 0; j < 4; j++) {
+          for (size_t i = 0; i < 4; i++) {
+            fblock[j * 4 + i] =
+                inPtr[c * image_size + ((y + j) * size_t(width) + (x + i))];
+          }
+        }
+        zfp_encode_block_float_2(zfp, fblock);
+      }
+    }
+  }
+
+  zfp_stream_flush(zfp);
+  (*outSize) = static_cast<unsigned int>(zfp_stream_compressed_size(zfp));
+
+  zfp_stream_close(zfp);
+
+  return true;
+}
+
+#endif
+
+//
+// -----------------------------------------------------------------
+//
+
+// heuristics
+#define TINYEXR_DIMENSION_THRESHOLD (1024 * 8192)
+
+// TODO(syoyo): Refactor function arguments.
+static bool DecodePixelData(/* out */ unsigned char **out_images,
+                            const int *requested_pixel_types,
+                            const unsigned char *data_ptr, size_t data_len,
+                            int compression_type, int line_order, int width,
+                            int height, int x_stride, int y, int line_no,
+                            int num_lines, size_t pixel_data_size,
+                            size_t num_attributes,
+                            const EXRAttribute *attributes, size_t num_channels,
+                            const EXRChannelInfo *channels,
+                            const std::vector<size_t> &channel_offset_list) {
+  if (compression_type == TINYEXR_COMPRESSIONTYPE_PIZ) {  // PIZ
+#if TINYEXR_USE_PIZ
+    if ((width == 0) || (num_lines == 0) || (pixel_data_size == 0)) {
+      // Invalid input #90
+      return false;
+    }
+
+    // Allocate original data size.
+    std::vector<unsigned char> outBuf(static_cast<size_t>(
+        static_cast<size_t>(width * num_lines) * pixel_data_size));
+    size_t tmpBufLen = outBuf.size();
+
+    bool ret = tinyexr::DecompressPiz(
+        reinterpret_cast<unsigned char *>(&outBuf.at(0)), data_ptr, tmpBufLen,
+        data_len, static_cast<int>(num_channels), channels, width, num_lines);
+
+    if (!ret) {
+      return false;
+    }
+
+    // For PIZ_COMPRESSION:
+    //   pixel sample data for channel 0 for scanline 0
+    //   pixel sample data for channel 1 for scanline 0
+    //   pixel sample data for channel ... for scanline 0
+    //   pixel sample data for channel n for scanline 0
+    //   pixel sample data for channel 0 for scanline 1
+    //   pixel sample data for channel 1 for scanline 1
+    //   pixel sample data for channel ... for scanline 1
+    //   pixel sample data for channel n for scanline 1
+    //   ...
+    for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+      if (channels[c].pixel_type == TINYEXR_PIXELTYPE_HALF) {
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const unsigned short *line_ptr = reinterpret_cast<unsigned short *>(
+              &outBuf.at(v * pixel_data_size * static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            FP16 hf;
+
+            // hf.u = line_ptr[u];
+            // use `cpy` to avoid unaligned memory access when compiler's
+            // optimization is on.
+            tinyexr::cpy2(&(hf.u), line_ptr + u);
+
+            tinyexr::swap2(reinterpret_cast<unsigned short *>(&hf.u));
+
+            if (requested_pixel_types[c] == TINYEXR_PIXELTYPE_HALF) {
+              unsigned short *image =
+                  reinterpret_cast<unsigned short **>(out_images)[c];
+              if (line_order == 0) {
+                image += (static_cast<size_t>(line_no) + v) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              } else {
+                image += static_cast<size_t>(
+                             (height - 1 - (line_no + static_cast<int>(v)))) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              }
+              *image = hf.u;
+            } else {  // HALF -> FLOAT
+              FP32 f32 = half_to_float(hf);
+              float *image = reinterpret_cast<float **>(out_images)[c];
+              size_t offset = 0;
+              if (line_order == 0) {
+                offset = (static_cast<size_t>(line_no) + v) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              } else {
+                offset = static_cast<size_t>(
+                             (height - 1 - (line_no + static_cast<int>(v)))) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              }
+              image += offset;
+              *image = f32.f;
+            }
+          }
+        }
+      } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_UINT) {
+        assert(requested_pixel_types[c] == TINYEXR_PIXELTYPE_UINT);
+
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const unsigned int *line_ptr = reinterpret_cast<unsigned int *>(
+              &outBuf.at(v * pixel_data_size * static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            unsigned int val;
+            // val = line_ptr[u];
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(&val);
+
+            unsigned int *image =
+                reinterpret_cast<unsigned int **>(out_images)[c];
+            if (line_order == 0) {
+              image += (static_cast<size_t>(line_no) + v) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            } else {
+              image += static_cast<size_t>(
+                           (height - 1 - (line_no + static_cast<int>(v)))) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            }
+            *image = val;
+          }
+        }
+      } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+        assert(requested_pixel_types[c] == TINYEXR_PIXELTYPE_FLOAT);
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const float *line_ptr = reinterpret_cast<float *>(&outBuf.at(
+              v * pixel_data_size * static_cast<size_t>(x_stride) +
+              channel_offset_list[c] * static_cast<size_t>(x_stride)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            float val;
+            // val = line_ptr[u];
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(reinterpret_cast<unsigned int *>(&val));
+
+            float *image = reinterpret_cast<float **>(out_images)[c];
+            if (line_order == 0) {
+              image += (static_cast<size_t>(line_no) + v) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            } else {
+              image += static_cast<size_t>(
+                           (height - 1 - (line_no + static_cast<int>(v)))) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            }
+            *image = val;
+          }
+        }
+      } else {
+        assert(0);
+      }
+    }
+#else
+    assert(0 && "PIZ is enabled in this build");
+    return false;
+#endif
+
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_ZIPS ||
+             compression_type == TINYEXR_COMPRESSIONTYPE_ZIP) {
+    // Allocate original data size.
+    std::vector<unsigned char> outBuf(static_cast<size_t>(width) *
+                                      static_cast<size_t>(num_lines) *
+                                      pixel_data_size);
+
+    unsigned long dstLen = static_cast<unsigned long>(outBuf.size());
+    assert(dstLen > 0);
+    if (!tinyexr::DecompressZip(
+            reinterpret_cast<unsigned char *>(&outBuf.at(0)), &dstLen, data_ptr,
+            static_cast<unsigned long>(data_len))) {
+      return false;
+    }
+
+    // For ZIP_COMPRESSION:
+    //   pixel sample data for channel 0 for scanline 0
+    //   pixel sample data for channel 1 for scanline 0
+    //   pixel sample data for channel ... for scanline 0
+    //   pixel sample data for channel n for scanline 0
+    //   pixel sample data for channel 0 for scanline 1
+    //   pixel sample data for channel 1 for scanline 1
+    //   pixel sample data for channel ... for scanline 1
+    //   pixel sample data for channel n for scanline 1
+    //   ...
+    for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+      if (channels[c].pixel_type == TINYEXR_PIXELTYPE_HALF) {
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const unsigned short *line_ptr = reinterpret_cast<unsigned short *>(
+              &outBuf.at(v * static_cast<size_t>(pixel_data_size) *
+                             static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            tinyexr::FP16 hf;
+
+            // hf.u = line_ptr[u];
+            tinyexr::cpy2(&(hf.u), line_ptr + u);
+
+            tinyexr::swap2(reinterpret_cast<unsigned short *>(&hf.u));
+
+            if (requested_pixel_types[c] == TINYEXR_PIXELTYPE_HALF) {
+              unsigned short *image =
+                  reinterpret_cast<unsigned short **>(out_images)[c];
+              if (line_order == 0) {
+                image += (static_cast<size_t>(line_no) + v) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              } else {
+                image += (static_cast<size_t>(height) - 1U -
+                          (static_cast<size_t>(line_no) + v)) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              }
+              *image = hf.u;
+            } else {  // HALF -> FLOAT
+              tinyexr::FP32 f32 = half_to_float(hf);
+              float *image = reinterpret_cast<float **>(out_images)[c];
+              size_t offset = 0;
+              if (line_order == 0) {
+                offset = (static_cast<size_t>(line_no) + v) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              } else {
+                offset = (static_cast<size_t>(height) - 1U -
+                          (static_cast<size_t>(line_no) + v)) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              }
+              image += offset;
+
+              *image = f32.f;
+            }
+          }
+        }
+      } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_UINT) {
+        assert(requested_pixel_types[c] == TINYEXR_PIXELTYPE_UINT);
+
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const unsigned int *line_ptr = reinterpret_cast<unsigned int *>(
+              &outBuf.at(v * pixel_data_size * static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            unsigned int val;
+            // val = line_ptr[u];
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(&val);
+
+            unsigned int *image =
+                reinterpret_cast<unsigned int **>(out_images)[c];
+            if (line_order == 0) {
+              image += (static_cast<size_t>(line_no) + v) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            } else {
+              image += (static_cast<size_t>(height) - 1U -
+                        (static_cast<size_t>(line_no) + v)) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            }
+            *image = val;
+          }
+        }
+      } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+        assert(requested_pixel_types[c] == TINYEXR_PIXELTYPE_FLOAT);
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const float *line_ptr = reinterpret_cast<float *>(
+              &outBuf.at(v * pixel_data_size * static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            float val;
+            // val = line_ptr[u];
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(reinterpret_cast<unsigned int *>(&val));
+
+            float *image = reinterpret_cast<float **>(out_images)[c];
+            if (line_order == 0) {
+              image += (static_cast<size_t>(line_no) + v) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            } else {
+              image += (static_cast<size_t>(height) - 1U -
+                        (static_cast<size_t>(line_no) + v)) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            }
+            *image = val;
+          }
+        }
+      } else {
+        assert(0);
+        return false;
+      }
+    }
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_RLE) {
+    // Allocate original data size.
+    std::vector<unsigned char> outBuf(static_cast<size_t>(width) *
+                                      static_cast<size_t>(num_lines) *
+                                      pixel_data_size);
+
+    unsigned long dstLen = static_cast<unsigned long>(outBuf.size());
+    if (dstLen == 0) {
+      return false;
+    }
+
+    if (!tinyexr::DecompressRle(
+            reinterpret_cast<unsigned char *>(&outBuf.at(0)), dstLen, data_ptr,
+            static_cast<unsigned long>(data_len))) {
+      return false;
+    }
+
+    // For RLE_COMPRESSION:
+    //   pixel sample data for channel 0 for scanline 0
+    //   pixel sample data for channel 1 for scanline 0
+    //   pixel sample data for channel ... for scanline 0
+    //   pixel sample data for channel n for scanline 0
+    //   pixel sample data for channel 0 for scanline 1
+    //   pixel sample data for channel 1 for scanline 1
+    //   pixel sample data for channel ... for scanline 1
+    //   pixel sample data for channel n for scanline 1
+    //   ...
+    for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+      if (channels[c].pixel_type == TINYEXR_PIXELTYPE_HALF) {
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const unsigned short *line_ptr = reinterpret_cast<unsigned short *>(
+              &outBuf.at(v * static_cast<size_t>(pixel_data_size) *
+                             static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            tinyexr::FP16 hf;
+
+            // hf.u = line_ptr[u];
+            tinyexr::cpy2(&(hf.u), line_ptr + u);
+
+            tinyexr::swap2(reinterpret_cast<unsigned short *>(&hf.u));
+
+            if (requested_pixel_types[c] == TINYEXR_PIXELTYPE_HALF) {
+              unsigned short *image =
+                  reinterpret_cast<unsigned short **>(out_images)[c];
+              if (line_order == 0) {
+                image += (static_cast<size_t>(line_no) + v) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              } else {
+                image += (static_cast<size_t>(height) - 1U -
+                          (static_cast<size_t>(line_no) + v)) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              }
+              *image = hf.u;
+            } else {  // HALF -> FLOAT
+              tinyexr::FP32 f32 = half_to_float(hf);
+              float *image = reinterpret_cast<float **>(out_images)[c];
+              if (line_order == 0) {
+                image += (static_cast<size_t>(line_no) + v) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              } else {
+                image += (static_cast<size_t>(height) - 1U -
+                          (static_cast<size_t>(line_no) + v)) *
+                             static_cast<size_t>(x_stride) +
+                         u;
+              }
+              *image = f32.f;
+            }
+          }
+        }
+      } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_UINT) {
+        assert(requested_pixel_types[c] == TINYEXR_PIXELTYPE_UINT);
+
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const unsigned int *line_ptr = reinterpret_cast<unsigned int *>(
+              &outBuf.at(v * pixel_data_size * static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            unsigned int val;
+            // val = line_ptr[u];
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(&val);
+
+            unsigned int *image =
+                reinterpret_cast<unsigned int **>(out_images)[c];
+            if (line_order == 0) {
+              image += (static_cast<size_t>(line_no) + v) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            } else {
+              image += (static_cast<size_t>(height) - 1U -
+                        (static_cast<size_t>(line_no) + v)) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            }
+            *image = val;
+          }
+        }
+      } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+        assert(requested_pixel_types[c] == TINYEXR_PIXELTYPE_FLOAT);
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const float *line_ptr = reinterpret_cast<float *>(
+              &outBuf.at(v * pixel_data_size * static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            float val;
+            // val = line_ptr[u];
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(reinterpret_cast<unsigned int *>(&val));
+
+            float *image = reinterpret_cast<float **>(out_images)[c];
+            if (line_order == 0) {
+              image += (static_cast<size_t>(line_no) + v) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            } else {
+              image += (static_cast<size_t>(height) - 1U -
+                        (static_cast<size_t>(line_no) + v)) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            }
+            *image = val;
+          }
+        }
+      } else {
+        assert(0);
+        return false;
+      }
+    }
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_ZFP) {
+#if TINYEXR_USE_ZFP
+    tinyexr::ZFPCompressionParam zfp_compression_param;
+    std::string e;
+    if (!tinyexr::FindZFPCompressionParam(&zfp_compression_param, attributes,
+                                          int(num_attributes), &e)) {
+      // This code path should not be reachable.
+      assert(0);
+      return false;
+    }
+
+    // Allocate original data size.
+    std::vector<unsigned char> outBuf(static_cast<size_t>(width) *
+                                      static_cast<size_t>(num_lines) *
+                                      pixel_data_size);
+
+    unsigned long dstLen = outBuf.size();
+    assert(dstLen > 0);
+    tinyexr::DecompressZfp(reinterpret_cast<float *>(&outBuf.at(0)), width,
+                           num_lines, num_channels, data_ptr,
+                           static_cast<unsigned long>(data_len),
+                           zfp_compression_param);
+
+    // For ZFP_COMPRESSION:
+    //   pixel sample data for channel 0 for scanline 0
+    //   pixel sample data for channel 1 for scanline 0
+    //   pixel sample data for channel ... for scanline 0
+    //   pixel sample data for channel n for scanline 0
+    //   pixel sample data for channel 0 for scanline 1
+    //   pixel sample data for channel 1 for scanline 1
+    //   pixel sample data for channel ... for scanline 1
+    //   pixel sample data for channel n for scanline 1
+    //   ...
+    for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+      assert(channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT);
+      if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+        assert(requested_pixel_types[c] == TINYEXR_PIXELTYPE_FLOAT);
+        for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+          const float *line_ptr = reinterpret_cast<float *>(
+              &outBuf.at(v * pixel_data_size * static_cast<size_t>(width) +
+                         channel_offset_list[c] * static_cast<size_t>(width)));
+          for (size_t u = 0; u < static_cast<size_t>(width); u++) {
+            float val;
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(reinterpret_cast<unsigned int *>(&val));
+
+            float *image = reinterpret_cast<float **>(out_images)[c];
+            if (line_order == 0) {
+              image += (static_cast<size_t>(line_no) + v) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            } else {
+              image += (static_cast<size_t>(height) - 1U -
+                        (static_cast<size_t>(line_no) + v)) *
+                           static_cast<size_t>(x_stride) +
+                       u;
+            }
+            *image = val;
+          }
+        }
+      } else {
+        assert(0);
+        return false;
+      }
+    }
+#else
+    (void)attributes;
+    (void)num_attributes;
+    (void)num_channels;
+    assert(0);
+    return false;
+#endif
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_NONE) {
+    for (size_t c = 0; c < num_channels; c++) {
+      for (size_t v = 0; v < static_cast<size_t>(num_lines); v++) {
+        if (channels[c].pixel_type == TINYEXR_PIXELTYPE_HALF) {
+          const unsigned short *line_ptr =
+              reinterpret_cast<const unsigned short *>(
+                  data_ptr + v * pixel_data_size * size_t(width) +
+                  channel_offset_list[c] * static_cast<size_t>(width));
+
+          if (requested_pixel_types[c] == TINYEXR_PIXELTYPE_HALF) {
+            unsigned short *outLine =
+                reinterpret_cast<unsigned short *>(out_images[c]);
+            if (line_order == 0) {
+              outLine += (size_t(y) + v) * size_t(x_stride);
+            } else {
+              outLine +=
+                  (size_t(height) - 1 - (size_t(y) + v)) * size_t(x_stride);
+            }
+
+            for (int u = 0; u < width; u++) {
+              tinyexr::FP16 hf;
+
+              // hf.u = line_ptr[u];
+              tinyexr::cpy2(&(hf.u), line_ptr + u);
+
+              tinyexr::swap2(reinterpret_cast<unsigned short *>(&hf.u));
+
+              outLine[u] = hf.u;
+            }
+          } else if (requested_pixel_types[c] == TINYEXR_PIXELTYPE_FLOAT) {
+            float *outLine = reinterpret_cast<float *>(out_images[c]);
+            if (line_order == 0) {
+              outLine += (size_t(y) + v) * size_t(x_stride);
+            } else {
+              outLine +=
+                  (size_t(height) - 1 - (size_t(y) + v)) * size_t(x_stride);
+            }
+
+            if (reinterpret_cast<const unsigned char *>(line_ptr + width) >
+                (data_ptr + data_len)) {
+              // Insufficient data size
+              return false;
+            }
+
+            for (int u = 0; u < width; u++) {
+              tinyexr::FP16 hf;
+
+              // address may not be aliged. use byte-wise copy for safety.#76
+              // hf.u = line_ptr[u];
+              tinyexr::cpy2(&(hf.u), line_ptr + u);
+
+              tinyexr::swap2(reinterpret_cast<unsigned short *>(&hf.u));
+
+              tinyexr::FP32 f32 = half_to_float(hf);
+
+              outLine[u] = f32.f;
+            }
+          } else {
+            assert(0);
+            return false;
+          }
+        } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+          const float *line_ptr = reinterpret_cast<const float *>(
+              data_ptr + v * pixel_data_size * size_t(width) +
+              channel_offset_list[c] * static_cast<size_t>(width));
+
+          float *outLine = reinterpret_cast<float *>(out_images[c]);
+          if (line_order == 0) {
+            outLine += (size_t(y) + v) * size_t(x_stride);
+          } else {
+            outLine +=
+                (size_t(height) - 1 - (size_t(y) + v)) * size_t(x_stride);
+          }
+
+          if (reinterpret_cast<const unsigned char *>(line_ptr + width) >
+              (data_ptr + data_len)) {
+            // Insufficient data size
+            return false;
+          }
+
+          for (int u = 0; u < width; u++) {
+            float val;
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(reinterpret_cast<unsigned int *>(&val));
+
+            outLine[u] = val;
+          }
+        } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_UINT) {
+          const unsigned int *line_ptr = reinterpret_cast<const unsigned int *>(
+              data_ptr + v * pixel_data_size * size_t(width) +
+              channel_offset_list[c] * static_cast<size_t>(width));
+
+          unsigned int *outLine =
+              reinterpret_cast<unsigned int *>(out_images[c]);
+          if (line_order == 0) {
+            outLine += (size_t(y) + v) * size_t(x_stride);
+          } else {
+            outLine +=
+                (size_t(height) - 1 - (size_t(y) + v)) * size_t(x_stride);
+          }
+
+          for (int u = 0; u < width; u++) {
+            if (reinterpret_cast<const unsigned char *>(line_ptr + u) >=
+                (data_ptr + data_len)) {
+              // Corrupsed data?
+              return false;
+            }
+
+            unsigned int val;
+            tinyexr::cpy4(&val, line_ptr + u);
+
+            tinyexr::swap4(reinterpret_cast<unsigned int *>(&val));
+
+            outLine[u] = val;
+          }
+        }
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool DecodeTiledPixelData(
+    unsigned char **out_images, int *width, int *height,
+    const int *requested_pixel_types, const unsigned char *data_ptr,
+    size_t data_len, int compression_type, int line_order, int data_width,
+    int data_height, int tile_offset_x, int tile_offset_y, int tile_size_x,
+    int tile_size_y, size_t pixel_data_size, size_t num_attributes,
+    const EXRAttribute *attributes, size_t num_channels,
+    const EXRChannelInfo *channels,
+    const std::vector<size_t> &channel_offset_list) {
+  // Here, data_width and data_height are the dimensions of the current (sub)level.
+  if (tile_size_x * tile_offset_x > data_width ||
+      tile_size_y * tile_offset_y > data_height) {
+    return false;
+  }
+
+  // Compute actual image size in a tile.
+  if ((tile_offset_x + 1) * tile_size_x >= data_width) {
+    (*width) = data_width - (tile_offset_x * tile_size_x);
+  } else {
+    (*width) = tile_size_x;
+  }
+
+  if ((tile_offset_y + 1) * tile_size_y >= data_height) {
+    (*height) = data_height - (tile_offset_y * tile_size_y);
+  } else {
+    (*height) = tile_size_y;
+  }
+
+  // Image size = tile size.
+  return DecodePixelData(out_images, requested_pixel_types, data_ptr, data_len,
+                         compression_type, line_order, (*width), tile_size_y,
+                         /* stride */ tile_size_x, /* y */ 0, /* line_no */ 0,
+                         (*height), pixel_data_size, num_attributes, attributes,
+                         num_channels, channels, channel_offset_list);
+}
+
+static bool ComputeChannelLayout(std::vector<size_t> *channel_offset_list,
+                                 int *pixel_data_size, size_t *channel_offset,
+                                 int num_channels,
+                                 const EXRChannelInfo *channels) {
+  channel_offset_list->resize(static_cast<size_t>(num_channels));
+
+  (*pixel_data_size) = 0;
+  (*channel_offset) = 0;
+
+  for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+    (*channel_offset_list)[c] = (*channel_offset);
+    if (channels[c].pixel_type == TINYEXR_PIXELTYPE_HALF) {
+      (*pixel_data_size) += sizeof(unsigned short);
+      (*channel_offset) += sizeof(unsigned short);
+    } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+      (*pixel_data_size) += sizeof(float);
+      (*channel_offset) += sizeof(float);
+    } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_UINT) {
+      (*pixel_data_size) += sizeof(unsigned int);
+      (*channel_offset) += sizeof(unsigned int);
+    } else {
+      // ???
+      return false;
+    }
+  }
+  return true;
+}
+
+static unsigned char **AllocateImage(int num_channels,
+                                     const EXRChannelInfo *channels,
+                                     const int *requested_pixel_types,
+                                     int data_width, int data_height) {
+  unsigned char **images =
+      reinterpret_cast<unsigned char **>(static_cast<float **>(
+          malloc(sizeof(float *) * static_cast<size_t>(num_channels))));
+
+  for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+    size_t data_len =
+        static_cast<size_t>(data_width) * static_cast<size_t>(data_height);
+    if (channels[c].pixel_type == TINYEXR_PIXELTYPE_HALF) {
+      // pixel_data_size += sizeof(unsigned short);
+      // channel_offset += sizeof(unsigned short);
+      // Alloc internal image for half type.
+      if (requested_pixel_types[c] == TINYEXR_PIXELTYPE_HALF) {
+        images[c] =
+            reinterpret_cast<unsigned char *>(static_cast<unsigned short *>(
+                malloc(sizeof(unsigned short) * data_len)));
+      } else if (requested_pixel_types[c] == TINYEXR_PIXELTYPE_FLOAT) {
+        images[c] = reinterpret_cast<unsigned char *>(
+            static_cast<float *>(malloc(sizeof(float) * data_len)));
+      } else {
+        assert(0);
+      }
+    } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+      // pixel_data_size += sizeof(float);
+      // channel_offset += sizeof(float);
+      images[c] = reinterpret_cast<unsigned char *>(
+          static_cast<float *>(malloc(sizeof(float) * data_len)));
+    } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_UINT) {
+      // pixel_data_size += sizeof(unsigned int);
+      // channel_offset += sizeof(unsigned int);
+      images[c] = reinterpret_cast<unsigned char *>(
+          static_cast<unsigned int *>(malloc(sizeof(unsigned int) * data_len)));
+    } else {
+      assert(0);
+    }
+  }
+
+  return images;
+}
+
+#ifdef _WIN32
+static inline std::wstring UTF8ToWchar(const std::string &str) {
+  int wstr_size =
+      MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), NULL, 0);
+  std::wstring wstr(wstr_size, 0);
+  MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), &wstr[0],
+                      (int)wstr.size());
+  return wstr;
+}
+#endif
+
+
+static int ParseEXRHeader(HeaderInfo *info, bool *empty_header,
+                          const EXRVersion *version, std::string *err,
+                          const unsigned char *buf, size_t size) {
+  const char *marker = reinterpret_cast<const char *>(&buf[0]);
+
+  if (empty_header) {
+    (*empty_header) = false;
+  }
+
+  if (version->multipart) {
+    if (size > 0 && marker[0] == '\0') {
+      // End of header list.
+      if (empty_header) {
+        (*empty_header) = true;
+      }
+      return TINYEXR_SUCCESS;
+    }
+  }
+
+  // According to the spec, the header of every OpenEXR file must contain at
+  // least the following attributes:
+  //
+  // channels chlist
+  // compression compression
+  // dataWindow box2i
+  // displayWindow box2i
+  // lineOrder lineOrder
+  // pixelAspectRatio float
+  // screenWindowCenter v2f
+  // screenWindowWidth float
+  bool has_channels = false;
+  bool has_compression = false;
+  bool has_data_window = false;
+  bool has_display_window = false;
+  bool has_line_order = false;
+  bool has_pixel_aspect_ratio = false;
+  bool has_screen_window_center = false;
+  bool has_screen_window_width = false;
+  bool has_name = false;
+  bool has_type = false;
+
+  info->name.clear();
+  info->type.clear();
+
+  info->data_window.min_x = 0;
+  info->data_window.min_y = 0;
+  info->data_window.max_x = 0;
+  info->data_window.max_y = 0;
+  info->line_order = 0;  // @fixme
+  info->display_window.min_x = 0;
+  info->display_window.min_y = 0;
+  info->display_window.max_x = 0;
+  info->display_window.max_y = 0;
+  info->screen_window_center[0] = 0.0f;
+  info->screen_window_center[1] = 0.0f;
+  info->screen_window_width = -1.0f;
+  info->pixel_aspect_ratio = -1.0f;
+
+  info->tiled = 0;
+  info->tile_size_x = -1;
+  info->tile_size_y = -1;
+  info->tile_level_mode = -1;
+  info->tile_rounding_mode = -1;
+
+  info->attributes.clear();
+
+  // Read attributes
+  size_t orig_size = size;
+  for (size_t nattr = 0; nattr < TINYEXR_MAX_HEADER_ATTRIBUTES; nattr++) {
+    if (0 == size) {
+      if (err) {
+        (*err) += "Insufficient data size for attributes.\n";
+      }
+      return TINYEXR_ERROR_INVALID_DATA;
+    } else if (marker[0] == '\0') {
+      size--;
+      break;
+    }
+
+    std::string attr_name;
+    std::string attr_type;
+    std::vector<unsigned char> data;
+    size_t marker_size;
+    if (!tinyexr::ReadAttribute(&attr_name, &attr_type, &data, &marker_size,
+                                marker, size)) {
+      if (err) {
+        (*err) += "Failed to read attribute.\n";
+      }
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+    marker += marker_size;
+    size -= marker_size;
+
+    // For a multipart file, the version field 9th bit is 0.
+    if ((version->tiled || version->multipart || version->non_image) && attr_name.compare("tiles") == 0) {
+      unsigned int x_size, y_size;
+      unsigned char tile_mode;
+      if (data.size() != 9) {
+        if (err) {
+          (*err) += "(ParseEXRHeader) Invalid attribute data size. Attribute data size must be 9.\n";
+        }
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+
+      assert(data.size() == 9);
+      memcpy(&x_size, &data.at(0), sizeof(int));
+      memcpy(&y_size, &data.at(4), sizeof(int));
+      tile_mode = data[8];
+      tinyexr::swap4(&x_size);
+      tinyexr::swap4(&y_size);
+
+      if (x_size > static_cast<unsigned int>(std::numeric_limits<int>::max()) ||
+          y_size > static_cast<unsigned int>(std::numeric_limits<int>::max())) {
+        if (err) {
+          (*err) = "Tile sizes were invalid.";
+        }
+        return TINYEXR_ERROR_UNSUPPORTED_FORMAT;
+      }
+
+      info->tile_size_x = static_cast<int>(x_size);
+      info->tile_size_y = static_cast<int>(y_size);
+
+      // mode = levelMode + roundingMode * 16
+      info->tile_level_mode = tile_mode & 0x3;
+      info->tile_rounding_mode = (tile_mode >> 4) & 0x1;
+      info->tiled = 1;
+    } else if (attr_name.compare("compression") == 0) {
+      bool ok = false;
+      if (data[0] < TINYEXR_COMPRESSIONTYPE_PIZ) {
+        ok = true;
+      }
+
+      if (data[0] == TINYEXR_COMPRESSIONTYPE_PIZ) {
+#if TINYEXR_USE_PIZ
+        ok = true;
+#else
+        if (err) {
+          (*err) = "PIZ compression is not supported.";
+        }
+        return TINYEXR_ERROR_UNSUPPORTED_FORMAT;
+#endif
+      }
+
+      if (data[0] == TINYEXR_COMPRESSIONTYPE_ZFP) {
+#if TINYEXR_USE_ZFP
+        ok = true;
+#else
+        if (err) {
+          (*err) = "ZFP compression is not supported.";
+        }
+        return TINYEXR_ERROR_UNSUPPORTED_FORMAT;
+#endif
+      }
+
+      if (!ok) {
+        if (err) {
+          (*err) = "Unknown compression type.";
+        }
+        return TINYEXR_ERROR_UNSUPPORTED_FORMAT;
+      }
+
+      info->compression_type = static_cast<int>(data[0]);
+      has_compression = true;
+
+    } else if (attr_name.compare("channels") == 0) {
+      // name: zero-terminated string, from 1 to 255 bytes long
+      // pixel type: int, possible values are: UINT = 0 HALF = 1 FLOAT = 2
+      // pLinear: unsigned char, possible values are 0 and 1
+      // reserved: three chars, should be zero
+      // xSampling: int
+      // ySampling: int
+
+      if (!ReadChannelInfo(info->channels, data)) {
+        if (err) {
+          (*err) += "Failed to parse channel info.\n";
+        }
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+
+      if (info->channels.size() < 1) {
+        if (err) {
+          (*err) += "# of channels is zero.\n";
+        }
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+
+      has_channels = true;
+
+    } else if (attr_name.compare("dataWindow") == 0) {
+      if (data.size() >= 16) {
+        memcpy(&info->data_window.min_x, &data.at(0), sizeof(int));
+        memcpy(&info->data_window.min_y, &data.at(4), sizeof(int));
+        memcpy(&info->data_window.max_x, &data.at(8), sizeof(int));
+        memcpy(&info->data_window.max_y, &data.at(12), sizeof(int));
+        tinyexr::swap4(&info->data_window.min_x);
+        tinyexr::swap4(&info->data_window.min_y);
+        tinyexr::swap4(&info->data_window.max_x);
+        tinyexr::swap4(&info->data_window.max_y);
+        has_data_window = true;
+      }
+    } else if (attr_name.compare("displayWindow") == 0) {
+      if (data.size() >= 16) {
+        memcpy(&info->display_window.min_x, &data.at(0), sizeof(int));
+        memcpy(&info->display_window.min_y, &data.at(4), sizeof(int));
+        memcpy(&info->display_window.max_x, &data.at(8), sizeof(int));
+        memcpy(&info->display_window.max_y, &data.at(12), sizeof(int));
+        tinyexr::swap4(&info->display_window.min_x);
+        tinyexr::swap4(&info->display_window.min_y);
+        tinyexr::swap4(&info->display_window.max_x);
+        tinyexr::swap4(&info->display_window.max_y);
+
+        has_display_window = true;
+      }
+    } else if (attr_name.compare("lineOrder") == 0) {
+      if (data.size() >= 1) {
+        info->line_order = static_cast<int>(data[0]);
+        has_line_order = true;
+      }
+    } else if (attr_name.compare("pixelAspectRatio") == 0) {
+      if (data.size() >= sizeof(float)) {
+        memcpy(&info->pixel_aspect_ratio, &data.at(0), sizeof(float));
+        tinyexr::swap4(&info->pixel_aspect_ratio);
+        has_pixel_aspect_ratio = true;
+      }
+    } else if (attr_name.compare("screenWindowCenter") == 0) {
+      if (data.size() >= 8) {
+        memcpy(&info->screen_window_center[0], &data.at(0), sizeof(float));
+        memcpy(&info->screen_window_center[1], &data.at(4), sizeof(float));
+        tinyexr::swap4(&info->screen_window_center[0]);
+        tinyexr::swap4(&info->screen_window_center[1]);
+        has_screen_window_center = true;
+      }
+    } else if (attr_name.compare("screenWindowWidth") == 0) {
+      if (data.size() >= sizeof(float)) {
+        memcpy(&info->screen_window_width, &data.at(0), sizeof(float));
+        tinyexr::swap4(&info->screen_window_width);
+
+        has_screen_window_width = true;
+      }
+    } else if (attr_name.compare("chunkCount") == 0) {
+      if (data.size() >= sizeof(int)) {
+        memcpy(&info->chunk_count, &data.at(0), sizeof(int));
+        tinyexr::swap4(&info->chunk_count);
+      }
+    } else if (attr_name.compare("name") == 0) {
+      if (!data.empty() && data[0]) {
+        data.push_back(0);
+        size_t len = strlen(reinterpret_cast<const char*>(&data[0]));
+        info->name.resize(len);
+        info->name.assign(reinterpret_cast<const char*>(&data[0]), len);
+        has_name = true;
+      }
+    } else if (attr_name.compare("type") == 0) {
+      if (!data.empty() && data[0]) {
+        data.push_back(0);
+        size_t len = strlen(reinterpret_cast<const char*>(&data[0]));
+        info->type.resize(len);
+        info->type.assign(reinterpret_cast<const char*>(&data[0]), len);
+        has_type = true;
+      }
+    } else {
+      // Custom attribute(up to TINYEXR_MAX_CUSTOM_ATTRIBUTES)
+      if (info->attributes.size() < TINYEXR_MAX_CUSTOM_ATTRIBUTES) {
+        EXRAttribute attrib;
+#ifdef _MSC_VER
+        strncpy_s(attrib.name, attr_name.c_str(), 255);
+        strncpy_s(attrib.type, attr_type.c_str(), 255);
+#else
+        strncpy(attrib.name, attr_name.c_str(), 255);
+        strncpy(attrib.type, attr_type.c_str(), 255);
+#endif
+        attrib.name[255] = '\0';
+        attrib.type[255] = '\0';
+        attrib.size = static_cast<int>(data.size());
+        attrib.value = static_cast<unsigned char *>(malloc(data.size()));
+        memcpy(reinterpret_cast<char *>(attrib.value), &data.at(0),
+               data.size());
+        info->attributes.push_back(attrib);
+      }
+    }
+  }
+
+  // Check if required attributes exist
+  {
+    std::stringstream ss_err;
+
+    if (!has_compression) {
+      ss_err << "\"compression\" attribute not found in the header."
+             << std::endl;
+    }
+
+    if (!has_channels) {
+      ss_err << "\"channels\" attribute not found in the header." << std::endl;
+    }
+
+    if (!has_line_order) {
+      ss_err << "\"lineOrder\" attribute not found in the header." << std::endl;
+    }
+
+    if (!has_display_window) {
+      ss_err << "\"displayWindow\" attribute not found in the header."
+             << std::endl;
+    }
+
+    if (!has_data_window) {
+      ss_err << "\"dataWindow\" attribute not found in the header or invalid."
+             << std::endl;
+    }
+
+    if (!has_pixel_aspect_ratio) {
+      ss_err << "\"pixelAspectRatio\" attribute not found in the header."
+             << std::endl;
+    }
+
+    if (!has_screen_window_width) {
+      ss_err << "\"screenWindowWidth\" attribute not found in the header."
+             << std::endl;
+    }
+
+    if (!has_screen_window_center) {
+      ss_err << "\"screenWindowCenter\" attribute not found in the header."
+             << std::endl;
+    }
+
+    if (version->multipart || version->non_image) {
+      if (!has_name) {
+        ss_err << "\"name\" attribute not found in the header."
+          << std::endl;
+      }
+      if (!has_type) {
+        ss_err << "\"type\" attribute not found in the header."
+          << std::endl;
+      }
+    }
+
+    if (!(ss_err.str().empty())) {
+      if (err) {
+        (*err) += ss_err.str();
+      }
+      return TINYEXR_ERROR_INVALID_HEADER;
+    }
+  }
+
+  info->header_len = static_cast<unsigned int>(orig_size - size);
+
+  return TINYEXR_SUCCESS;
+}
+
+// C++ HeaderInfo to C EXRHeader conversion.
+static bool ConvertHeader(EXRHeader *exr_header, const HeaderInfo &info, std::string *warn, std::string *err) {
+  exr_header->pixel_aspect_ratio = info.pixel_aspect_ratio;
+  exr_header->screen_window_center[0] = info.screen_window_center[0];
+  exr_header->screen_window_center[1] = info.screen_window_center[1];
+  exr_header->screen_window_width = info.screen_window_width;
+  exr_header->chunk_count = info.chunk_count;
+  exr_header->display_window.min_x = info.display_window.min_x;
+  exr_header->display_window.min_y = info.display_window.min_y;
+  exr_header->display_window.max_x = info.display_window.max_x;
+  exr_header->display_window.max_y = info.display_window.max_y;
+  exr_header->data_window.min_x = info.data_window.min_x;
+  exr_header->data_window.min_y = info.data_window.min_y;
+  exr_header->data_window.max_x = info.data_window.max_x;
+  exr_header->data_window.max_y = info.data_window.max_y;
+  exr_header->line_order = info.line_order;
+  exr_header->compression_type = info.compression_type;
+  exr_header->tiled = info.tiled;
+  exr_header->tile_size_x = info.tile_size_x;
+  exr_header->tile_size_y = info.tile_size_y;
+  exr_header->tile_level_mode = info.tile_level_mode;
+  exr_header->tile_rounding_mode = info.tile_rounding_mode;
+
+  EXRSetNameAttr(exr_header, info.name.c_str());
+
+  bool valid = true;
+
+  if (!info.type.empty()) {
+    if (info.type == "scanlineimage") {
+      if (exr_header->tiled) {
+        if (err) {
+          (*err) += "(ConvertHeader) tiled bit must be off for `scanlineimage` type.\n";
+        }
+        valid = false;
+      }
+    } else if (info.type == "tiledimage") {
+      if (!exr_header->tiled) {
+        if (err) {
+          (*err) += "(ConvertHeader) tiled bit must be on for `tiledimage` type.\n";
+        }
+        valid = false;
+      }
+    } else if (info.type == "deeptile") {
+      exr_header->non_image = 1;
+      if (!exr_header->tiled) {
+        if (err) {
+          (*err) += "(ConvertHeader) tiled bit must be on for `deeptile` type.\n";
+        }
+        valid = false;
+      }
+    } else if (info.type == "deepscanline") {
+      exr_header->non_image = 1;
+      if (exr_header->tiled) {
+        if (err) {
+          (*err) += "(ConvertHeader) tiled bit must be off for `deepscanline` type.\n";
+        }
+        valid = false;
+      }
+    } else {
+      if (warn) {
+        std::stringstream ss;
+        ss << "(ConvertHeader) Unsupported or unknown info.type: " << info.type << "\n";
+        (*warn) += ss.str();
+      }
+    }
+  }
+
+  exr_header->num_channels = static_cast<int>(info.channels.size());
+
+  exr_header->channels = static_cast<EXRChannelInfo *>(malloc(
+      sizeof(EXRChannelInfo) * static_cast<size_t>(exr_header->num_channels)));
+  for (size_t c = 0; c < static_cast<size_t>(exr_header->num_channels); c++) {
+#ifdef _MSC_VER
+    strncpy_s(exr_header->channels[c].name, info.channels[c].name.c_str(), 255);
+#else
+    strncpy(exr_header->channels[c].name, info.channels[c].name.c_str(), 255);
+#endif
+    // manually add '\0' for safety.
+    exr_header->channels[c].name[255] = '\0';
+
+    exr_header->channels[c].pixel_type = info.channels[c].pixel_type;
+    exr_header->channels[c].p_linear = info.channels[c].p_linear;
+    exr_header->channels[c].x_sampling = info.channels[c].x_sampling;
+    exr_header->channels[c].y_sampling = info.channels[c].y_sampling;
+  }
+
+  exr_header->pixel_types = static_cast<int *>(
+      malloc(sizeof(int) * static_cast<size_t>(exr_header->num_channels)));
+  for (size_t c = 0; c < static_cast<size_t>(exr_header->num_channels); c++) {
+    exr_header->pixel_types[c] = info.channels[c].pixel_type;
+  }
+
+  // Initially fill with values of `pixel_types`
+  exr_header->requested_pixel_types = static_cast<int *>(
+      malloc(sizeof(int) * static_cast<size_t>(exr_header->num_channels)));
+  for (size_t c = 0; c < static_cast<size_t>(exr_header->num_channels); c++) {
+    exr_header->requested_pixel_types[c] = info.channels[c].pixel_type;
+  }
+
+  exr_header->num_custom_attributes = static_cast<int>(info.attributes.size());
+
+  if (exr_header->num_custom_attributes > 0) {
+    // TODO(syoyo): Report warning when # of attributes exceeds
+    // `TINYEXR_MAX_CUSTOM_ATTRIBUTES`
+    if (exr_header->num_custom_attributes > TINYEXR_MAX_CUSTOM_ATTRIBUTES) {
+      exr_header->num_custom_attributes = TINYEXR_MAX_CUSTOM_ATTRIBUTES;
+    }
+
+    exr_header->custom_attributes = static_cast<EXRAttribute *>(malloc(
+        sizeof(EXRAttribute) * size_t(exr_header->num_custom_attributes)));
+
+    for (size_t i = 0; i < info.attributes.size(); i++) {
+      memcpy(exr_header->custom_attributes[i].name, info.attributes[i].name,
+             256);
+      memcpy(exr_header->custom_attributes[i].type, info.attributes[i].type,
+             256);
+      exr_header->custom_attributes[i].size = info.attributes[i].size;
+      // Just copy pointer
+      exr_header->custom_attributes[i].value = info.attributes[i].value;
+    }
+
+  } else {
+    exr_header->custom_attributes = NULL;
+  }
+
+  exr_header->header_len = info.header_len;
+
+  return true;
+}
+
+struct OffsetData {
+  OffsetData() : num_x_levels(0), num_y_levels(0) {}
+  std::vector<std::vector<std::vector <tinyexr::tinyexr_uint64> > > offsets;
+  int	num_x_levels;
+  int	num_y_levels;
+};
+
+int LevelIndex(int lx, int ly, int tile_level_mode, int num_x_levels) {
+  switch (tile_level_mode) {
+  case TINYEXR_TILE_ONE_LEVEL:
+    return 0;
+
+  case TINYEXR_TILE_MIPMAP_LEVELS:
+    return lx;
+
+  case TINYEXR_TILE_RIPMAP_LEVELS:
+    return lx + ly * num_x_levels;
+
+  default:
+    assert(false);
+  }
+  return 0;
+}
+
+static int LevelSize(int toplevel_size, int level, int tile_rounding_mode) {
+  assert(level >= 0);
+
+  int b = (int)(1u << (unsigned)level);
+  int level_size = toplevel_size / b;
+
+  if (tile_rounding_mode == TINYEXR_TILE_ROUND_UP && level_size * b < toplevel_size)
+    level_size += 1;
+
+  return std::max(level_size, 1);
+}
+
+static int DecodeTiledLevel(EXRImage* exr_image, const EXRHeader* exr_header,
+  const OffsetData& offset_data,
+  const std::vector<size_t>& channel_offset_list,
+  int pixel_data_size,
+  const unsigned char* head, const size_t size,
+  std::string* err) {
+  int num_channels = exr_header->num_channels;
+
+  int level_index = LevelIndex(exr_image->level_x, exr_image->level_y, exr_header->tile_level_mode, offset_data.num_x_levels);
+  int num_y_tiles = (int)offset_data.offsets[level_index].size();
+  assert(num_y_tiles);
+  int num_x_tiles = (int)offset_data.offsets[level_index][0].size();
+  assert(num_x_tiles);
+  int num_tiles = num_x_tiles * num_y_tiles;
+
+  int err_code = TINYEXR_SUCCESS;
+
+  enum {
+    EF_SUCCESS = 0,
+    EF_INVALID_DATA = 1,
+    EF_INSUFFICIENT_DATA = 2,
+    EF_FAILED_TO_DECODE = 4
+  };
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+  std::atomic<unsigned> error_flag(EF_SUCCESS);
+#else
+  unsigned error_flag(EF_SUCCESS);
+#endif
+  
+  // Although the spec says : "...the data window is subdivided into an array of smaller rectangles...",
+  // the IlmImf library allows the dimensions of the tile to be larger (or equal) than the dimensions of the data window.
+#if 0
+  if ((exr_header->tile_size_x > exr_image->width || exr_header->tile_size_y > exr_image->height) &&
+    exr_image->level_x == 0 && exr_image->level_y == 0) {
+    if (err) {
+      (*err) += "Failed to decode tile data.\n";
+    }
+    err_code = TINYEXR_ERROR_INVALID_DATA;
+  }
+#endif
+  exr_image->tiles = static_cast<EXRTile*>(
+    calloc(sizeof(EXRTile), static_cast<size_t>(num_tiles)));
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+  std::vector<std::thread> workers;
+  std::atomic<int> tile_count(0);
+
+  int num_threads = std::max(1, int(std::thread::hardware_concurrency()));
+  if (num_threads > int(num_tiles)) {
+    num_threads = int(num_tiles);
+  }
+
+  for (int t = 0; t < num_threads; t++) {
+    workers.emplace_back(std::thread([&]()
+      {
+        int tile_idx = 0;
+        while ((tile_idx = tile_count++) < num_tiles) {
+
+#else
+#if TINYEXR_USE_OPENMP
+#pragma omp parallel for
+#endif
+  for (int tile_idx = 0; tile_idx < num_tiles; tile_idx++) {
+#endif
+    // Allocate memory for each tile.
+    exr_image->tiles[tile_idx].images = tinyexr::AllocateImage(
+      num_channels, exr_header->channels,
+      exr_header->requested_pixel_types, exr_header->tile_size_x,
+      exr_header->tile_size_y);
+
+    int x_tile = tile_idx % num_x_tiles;
+    int y_tile = tile_idx / num_x_tiles;
+    // 16 byte: tile coordinates
+    // 4 byte : data size
+    // ~      : data(uncompressed or compressed)
+    tinyexr::tinyexr_uint64 offset = offset_data.offsets[level_index][y_tile][x_tile];
+    if (offset + sizeof(int) * 5 > size) {
+      // Insufficient data size.
+      error_flag |= EF_INSUFFICIENT_DATA; 
+      continue;
+    }
+
+    size_t data_size =
+      size_t(size - (offset + sizeof(int) * 5));
+    const unsigned char* data_ptr =
+      reinterpret_cast<const unsigned char*>(head + offset);
+
+    int tile_coordinates[4];
+    memcpy(tile_coordinates, data_ptr, sizeof(int) * 4);
+    tinyexr::swap4(&tile_coordinates[0]);
+    tinyexr::swap4(&tile_coordinates[1]);
+    tinyexr::swap4(&tile_coordinates[2]);
+    tinyexr::swap4(&tile_coordinates[3]);
+
+    if (tile_coordinates[2] != exr_image->level_x) {
+      // Invalid data.
+      error_flag |= EF_INVALID_DATA;
+      continue;
+    }
+    if (tile_coordinates[3] != exr_image->level_y) {
+      // Invalid data.
+      error_flag |= EF_INVALID_DATA;
+      continue;
+    }
+
+    int data_len;
+    memcpy(&data_len, data_ptr + 16,
+      sizeof(int));  // 16 = sizeof(tile_coordinates)
+    tinyexr::swap4(&data_len);
+
+    if (data_len < 2 || size_t(data_len) > data_size) {
+      // Insufficient data size.
+      error_flag |= EF_INSUFFICIENT_DATA;
+      continue;
+    }
+
+    // Move to data addr: 20 = 16 + 4;
+    data_ptr += 20;
+    bool ret = tinyexr::DecodeTiledPixelData(
+      exr_image->tiles[tile_idx].images,
+      &(exr_image->tiles[tile_idx].width),
+      &(exr_image->tiles[tile_idx].height),
+      exr_header->requested_pixel_types, data_ptr,
+      static_cast<size_t>(data_len), exr_header->compression_type,
+      exr_header->line_order,
+      exr_image->width, exr_image->height,
+      tile_coordinates[0], tile_coordinates[1], exr_header->tile_size_x,
+      exr_header->tile_size_y, static_cast<size_t>(pixel_data_size),
+      static_cast<size_t>(exr_header->num_custom_attributes),
+      exr_header->custom_attributes,
+      static_cast<size_t>(exr_header->num_channels),
+      exr_header->channels, channel_offset_list);
+
+    if (!ret) {
+      // Failed to decode tile data.
+      error_flag |= EF_FAILED_TO_DECODE;
+    }
+
+    exr_image->tiles[tile_idx].offset_x = tile_coordinates[0];
+    exr_image->tiles[tile_idx].offset_y = tile_coordinates[1];
+    exr_image->tiles[tile_idx].level_x = tile_coordinates[2];
+    exr_image->tiles[tile_idx].level_y = tile_coordinates[3];
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+  }  
+        }));
+    }  // num_thread loop
+
+    for (auto& t : workers) {
+      t.join();
+    }
+
+#else
+  } // parallel for
+#endif
+
+  // Even in the event of an error, the reserved memory may be freed.
+  exr_image->num_channels = num_channels;
+  exr_image->num_tiles = static_cast<int>(num_tiles);
+
+  if (error_flag)  err_code = TINYEXR_ERROR_INVALID_DATA;
+  if (err) {
+    if (error_flag & EF_INSUFFICIENT_DATA) {
+      (*err) += "Insufficient data length.\n";
+    }
+    if (error_flag & EF_FAILED_TO_DECODE) {
+      (*err) += "Failed to decode tile data.\n";
+    }
+  }
+  return err_code;
+}
+
+static int DecodeChunk(EXRImage *exr_image, const EXRHeader *exr_header,
+                       const OffsetData& offset_data,
+                       const unsigned char *head, const size_t size,
+                       std::string *err) {
+  int num_channels = exr_header->num_channels;
+
+  int num_scanline_blocks = 1;
+  if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_ZIP) {
+    num_scanline_blocks = 16;
+  } else if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_PIZ) {
+    num_scanline_blocks = 32;
+  } else if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_ZFP) {
+    num_scanline_blocks = 16;
+
+#if TINYEXR_USE_ZFP
+    tinyexr::ZFPCompressionParam zfp_compression_param;
+    if (!FindZFPCompressionParam(&zfp_compression_param,
+                                 exr_header->custom_attributes,
+                                 int(exr_header->num_custom_attributes), err)) {
+      return TINYEXR_ERROR_INVALID_HEADER;
+    }
+#endif
+  }
+
+  if (exr_header->data_window.max_x < exr_header->data_window.min_x ||
+      exr_header->data_window.max_y < exr_header->data_window.min_y) {
+    if (err) {
+      (*err) += "Invalid data window.\n";
+    }
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+
+  int data_width =
+      exr_header->data_window.max_x - exr_header->data_window.min_x + 1;
+  int data_height =
+      exr_header->data_window.max_y - exr_header->data_window.min_y + 1;
+
+  // Do not allow too large data_width and data_height. header invalid?
+  {
+    if ((data_width > TINYEXR_DIMENSION_THRESHOLD) || (data_height > TINYEXR_DIMENSION_THRESHOLD)) {
+      if (err) {
+        std::stringstream ss;
+        ss << "data_with or data_height too large. data_width: " << data_width
+           << ", "
+           << "data_height = " << data_height << std::endl;
+        (*err) += ss.str();
+      }
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+    if (exr_header->tiled) {
+      if ((exr_header->tile_size_x > TINYEXR_DIMENSION_THRESHOLD) || (exr_header->tile_size_y > TINYEXR_DIMENSION_THRESHOLD)) {
+        if (err) {
+          std::stringstream ss;
+          ss << "tile with or tile height too large. tile width: " << exr_header->tile_size_x
+            << ", "
+            << "tile height = " << exr_header->tile_size_y << std::endl;
+          (*err) += ss.str();
+        }
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+    }
+  }
+
+  const std::vector<tinyexr::tinyexr_uint64>& offsets = offset_data.offsets[0][0];
+  size_t num_blocks = offsets.size();
+
+  std::vector<size_t> channel_offset_list;
+  int pixel_data_size = 0;
+  size_t channel_offset = 0;
+  if (!tinyexr::ComputeChannelLayout(&channel_offset_list, &pixel_data_size,
+                                     &channel_offset, num_channels,
+                                     exr_header->channels)) {
+    if (err) {
+      (*err) += "Failed to compute channel layout.\n";
+    }
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+  std::atomic<bool> invalid_data(false);
+#else
+  bool invalid_data(false);
+#endif
+
+  if (exr_header->tiled) {
+    // value check
+    if (exr_header->tile_size_x < 0) {
+      if (err) {
+        std::stringstream ss;
+        ss << "Invalid tile size x : " << exr_header->tile_size_x << "\n";
+        (*err) += ss.str();
+      }
+      return TINYEXR_ERROR_INVALID_HEADER;
+    }
+
+    if (exr_header->tile_size_y < 0) {
+      if (err) {
+        std::stringstream ss;
+        ss << "Invalid tile size y : " << exr_header->tile_size_y << "\n";
+        (*err) += ss.str();
+      }
+      return TINYEXR_ERROR_INVALID_HEADER;
+    }
+    if (exr_header->tile_level_mode != TINYEXR_TILE_RIPMAP_LEVELS) {
+      EXRImage* level_image = NULL;
+      for (int level = 0; level < offset_data.num_x_levels; ++level) {
+        if (!level_image) {
+          level_image = exr_image;
+        } else {
+          level_image->next_level = new EXRImage;
+          InitEXRImage(level_image->next_level);
+          level_image = level_image->next_level;
+        }
+        level_image->width =
+          LevelSize(exr_header->data_window.max_x - exr_header->data_window.min_x + 1, level, exr_header->tile_rounding_mode);
+        level_image->height =
+          LevelSize(exr_header->data_window.max_y - exr_header->data_window.min_y + 1, level, exr_header->tile_rounding_mode);
+        level_image->level_x = level;
+        level_image->level_y = level;
+
+        int ret = DecodeTiledLevel(level_image, exr_header,
+          offset_data,
+          channel_offset_list,
+          pixel_data_size,
+          head, size,
+          err);
+        if (ret != TINYEXR_SUCCESS) return ret;
+      }
+    } else {
+      EXRImage* level_image = NULL;
+      for (int level_y = 0; level_y < offset_data.num_y_levels; ++level_y)
+        for (int level_x = 0; level_x < offset_data.num_x_levels; ++level_x) {
+          if (!level_image) {
+            level_image = exr_image;
+          } else {
+            level_image->next_level = new EXRImage;
+            InitEXRImage(level_image->next_level);
+            level_image = level_image->next_level;
+          }
+
+          level_image->width =
+            LevelSize(exr_header->data_window.max_x - exr_header->data_window.min_x + 1, level_x, exr_header->tile_rounding_mode);
+          level_image->height =
+            LevelSize(exr_header->data_window.max_y - exr_header->data_window.min_y + 1, level_y, exr_header->tile_rounding_mode);
+          level_image->level_x = level_x;
+          level_image->level_y = level_y;
+
+          int ret = DecodeTiledLevel(level_image, exr_header,
+            offset_data,
+            channel_offset_list,
+            pixel_data_size,
+            head, size,
+            err);
+          if (ret != TINYEXR_SUCCESS) return ret;
+        }
+    }
+  } else {  // scanline format
+    // Don't allow too large image(256GB * pixel_data_size or more). Workaround
+    // for #104.
+    size_t total_data_len =
+        size_t(data_width) * size_t(data_height) * size_t(num_channels);
+    const bool total_data_len_overflown =
+        sizeof(void *) == 8 ? (total_data_len >= 0x4000000000) : false;
+    if ((total_data_len == 0) || total_data_len_overflown) {
+      if (err) {
+        std::stringstream ss;
+        ss << "Image data size is zero or too large: width = " << data_width
+           << ", height = " << data_height << ", channels = " << num_channels
+           << std::endl;
+        (*err) += ss.str();
+      }
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    exr_image->images = tinyexr::AllocateImage(
+        num_channels, exr_header->channels, exr_header->requested_pixel_types,
+        data_width, data_height);
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+    std::vector<std::thread> workers;
+    std::atomic<int> y_count(0);
+
+    int num_threads = std::max(1, int(std::thread::hardware_concurrency()));
+    if (num_threads > int(num_blocks)) {
+      num_threads = int(num_blocks);
+    }
+
+    for (int t = 0; t < num_threads; t++) {
+      workers.emplace_back(std::thread([&]() {
+        int y = 0;
+        while ((y = y_count++) < int(num_blocks)) {
+
+#else
+
+#if TINYEXR_USE_OPENMP
+#pragma omp parallel for
+#endif
+    for (int y = 0; y < static_cast<int>(num_blocks); y++) {
+
+#endif
+          size_t y_idx = static_cast<size_t>(y);
+
+          if (offsets[y_idx] + sizeof(int) * 2 > size) {
+            invalid_data = true;
+          } else {
+            // 4 byte: scan line
+            // 4 byte: data size
+            // ~     : pixel data(uncompressed or compressed)
+            size_t data_size =
+                size_t(size - (offsets[y_idx] + sizeof(int) * 2));
+            const unsigned char *data_ptr =
+                reinterpret_cast<const unsigned char *>(head + offsets[y_idx]);
+
+            int line_no;
+            memcpy(&line_no, data_ptr, sizeof(int));
+            int data_len;
+            memcpy(&data_len, data_ptr + 4, sizeof(int));
+            tinyexr::swap4(&line_no);
+            tinyexr::swap4(&data_len);
+
+            if (size_t(data_len) > data_size) {
+              invalid_data = true;
+
+            } else if ((line_no > (2 << 20)) || (line_no < -(2 << 20))) {
+              // Too large value. Assume this is invalid
+              // 2**20 = 1048576 = heuristic value.
+              invalid_data = true;
+            } else if (data_len == 0) {
+              // TODO(syoyo): May be ok to raise the threshold for example
+              // `data_len < 4`
+              invalid_data = true;
+            } else {
+              // line_no may be negative.
+              int end_line_no = (std::min)(line_no + num_scanline_blocks,
+                                           (exr_header->data_window.max_y + 1));
+
+              int num_lines = end_line_no - line_no;
+
+              if (num_lines <= 0) {
+                invalid_data = true;
+              } else {
+                // Move to data addr: 8 = 4 + 4;
+                data_ptr += 8;
+
+                // Adjust line_no with data_window.bmin.y
+
+                // overflow check
+                tinyexr_int64 lno =
+                    static_cast<tinyexr_int64>(line_no) -
+                    static_cast<tinyexr_int64>(exr_header->data_window.min_y);
+                if (lno > std::numeric_limits<int>::max()) {
+                  line_no = -1;  // invalid
+                } else if (lno < -std::numeric_limits<int>::max()) {
+                  line_no = -1;  // invalid
+                } else {
+                  line_no -= exr_header->data_window.min_y;
+                }
+
+                if (line_no < 0) {
+                  invalid_data = true;
+                } else {
+                  if (!tinyexr::DecodePixelData(
+                          exr_image->images, exr_header->requested_pixel_types,
+                          data_ptr, static_cast<size_t>(data_len),
+                          exr_header->compression_type, exr_header->line_order,
+                          data_width, data_height, data_width, y, line_no,
+                          num_lines, static_cast<size_t>(pixel_data_size),
+                          static_cast<size_t>(
+                              exr_header->num_custom_attributes),
+                          exr_header->custom_attributes,
+                          static_cast<size_t>(exr_header->num_channels),
+                          exr_header->channels, channel_offset_list)) {
+                    invalid_data = true;
+                  }
+                }
+              }
+            }
+          }
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+        }
+      }));
+    }
+
+    for (auto &t : workers) {
+      t.join();
+    }
+#else
+    }  // omp parallel
+#endif
+  }
+
+  if (invalid_data) {
+    if (err) {
+      (*err) += "Invalid data found when decoding pixels.\n";
+    }
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+
+  // Overwrite `pixel_type` with `requested_pixel_type`.
+  {
+    for (int c = 0; c < exr_header->num_channels; c++) {
+      exr_header->pixel_types[c] = exr_header->requested_pixel_types[c];
+    }
+  }
+
+  {
+    exr_image->num_channels = num_channels;
+
+    exr_image->width = data_width;
+    exr_image->height = data_height;
+  }
+
+  return TINYEXR_SUCCESS;
+}
+
+static bool ReconstructLineOffsets(
+    std::vector<tinyexr::tinyexr_uint64> *offsets, size_t n,
+    const unsigned char *head, const unsigned char *marker, const size_t size) {
+  assert(head < marker);
+  assert(offsets->size() == n);
+
+  for (size_t i = 0; i < n; i++) {
+    size_t offset = static_cast<size_t>(marker - head);
+    // Offset should not exceed whole EXR file/data size.
+    if ((offset + sizeof(tinyexr::tinyexr_uint64)) >= size) {
+      return false;
+    }
+
+    int y;
+    unsigned int data_len;
+
+    memcpy(&y, marker, sizeof(int));
+    memcpy(&data_len, marker + 4, sizeof(unsigned int));
+
+    if (data_len >= size) {
+      return false;
+    }
+
+    tinyexr::swap4(&y);
+    tinyexr::swap4(&data_len);
+
+    (*offsets)[i] = offset;
+
+    marker += data_len + 8;  // 8 = 4 bytes(y) + 4 bytes(data_len)
+  }
+
+  return true;
+}
+
+
+static int FloorLog2(unsigned x) {
+  //
+  // For x > 0, floorLog2(y) returns floor(log(x)/log(2)).
+  //
+  int y = 0;
+  while (x > 1) {
+    y += 1;
+    x >>= 1u;
+  }
+  return y;
+}
+
+
+static int CeilLog2(unsigned x) {
+  //
+  // For x > 0, ceilLog2(y) returns ceil(log(x)/log(2)).
+  //
+  int y = 0;
+  int r = 0;
+  while (x > 1) {
+    if (x & 1)
+      r = 1;
+
+    y += 1;
+    x >>= 1u;
+  }
+  return y + r;
+}
+
+static int RoundLog2(int x, int tile_rounding_mode) {
+  return (tile_rounding_mode == TINYEXR_TILE_ROUND_DOWN) ? FloorLog2(static_cast<unsigned>(x)) : CeilLog2(static_cast<unsigned>(x));
+}
+
+static int CalculateNumXLevels(const EXRHeader* exr_header) {
+  int min_x = exr_header->data_window.min_x;
+  int max_x = exr_header->data_window.max_x;
+  int min_y = exr_header->data_window.min_y;
+  int max_y = exr_header->data_window.max_y;
+
+  int num = 0;
+  switch (exr_header->tile_level_mode) {
+  case TINYEXR_TILE_ONE_LEVEL:
+
+    num = 1;
+    break;
+
+  case TINYEXR_TILE_MIPMAP_LEVELS:
+
+  {
+    int w = max_x - min_x + 1;
+    int h = max_y - min_y + 1;
+    num = RoundLog2(std::max(w, h), exr_header->tile_rounding_mode) + 1;
+  }
+  break;
+
+  case TINYEXR_TILE_RIPMAP_LEVELS:
+
+  {
+    int w = max_x - min_x + 1;
+    num = RoundLog2(w, exr_header->tile_rounding_mode) + 1;
+  }
+  break;
+
+  default:
+
+    assert(false);
+  }
+
+  return num;
+}
+
+static int CalculateNumYLevels(const EXRHeader* exr_header) {
+  int min_x = exr_header->data_window.min_x;
+  int max_x = exr_header->data_window.max_x;
+  int min_y = exr_header->data_window.min_y;
+  int max_y = exr_header->data_window.max_y;
+  int num = 0;
+
+  switch (exr_header->tile_level_mode) {
+  case TINYEXR_TILE_ONE_LEVEL:
+
+    num = 1;
+    break;
+
+  case TINYEXR_TILE_MIPMAP_LEVELS:
+
+  {
+    int w = max_x - min_x + 1;
+    int h = max_y - min_y + 1;
+    num = RoundLog2(std::max(w, h), exr_header->tile_rounding_mode) + 1;
+  }
+  break;
+
+  case TINYEXR_TILE_RIPMAP_LEVELS:
+
+  {
+    int h = max_y - min_y + 1;
+    num = RoundLog2(h, exr_header->tile_rounding_mode) + 1;
+  }
+  break;
+
+  default:
+
+    assert(false);
+  }
+
+  return num;
+}
+
+static void CalculateNumTiles(std::vector<int>& numTiles,
+  int toplevel_size,
+  int size,
+  int tile_rounding_mode) {
+  for (unsigned i = 0; i < numTiles.size(); i++) {
+    int l = LevelSize(toplevel_size, i, tile_rounding_mode);
+    assert(l <= std::numeric_limits<int>::max() - size + 1);
+
+    numTiles[i] = (l + size - 1) / size;
+  }
+}
+
+static void PrecalculateTileInfo(std::vector<int>& num_x_tiles,
+  std::vector<int>& num_y_tiles,
+  const EXRHeader* exr_header) {
+  int min_x = exr_header->data_window.min_x;
+  int max_x = exr_header->data_window.max_x;
+  int min_y = exr_header->data_window.min_y;
+  int max_y = exr_header->data_window.max_y;
+
+  int num_x_levels = CalculateNumXLevels(exr_header);
+  int num_y_levels = CalculateNumYLevels(exr_header);
+
+  num_x_tiles.resize(num_x_levels);
+  num_y_tiles.resize(num_y_levels);
+
+  CalculateNumTiles(num_x_tiles,
+    max_x - min_x + 1,
+    exr_header->tile_size_x,
+    exr_header->tile_rounding_mode);
+
+  CalculateNumTiles(num_y_tiles,
+    max_y - min_y + 1,
+    exr_header->tile_size_y,
+    exr_header->tile_rounding_mode);
+}
+
+static void InitSingleResolutionOffsets(OffsetData& offset_data, size_t num_blocks) {
+  offset_data.offsets.resize(1);
+  offset_data.offsets[0].resize(1);
+  offset_data.offsets[0][0].resize(num_blocks);
+  offset_data.num_x_levels = 1;
+  offset_data.num_y_levels = 1;
+}
+
+// Return sum of tile blocks.
+static int InitTileOffsets(OffsetData& offset_data,
+  const EXRHeader* exr_header,
+  const std::vector<int>& num_x_tiles,
+  const std::vector<int>& num_y_tiles) {
+  int num_tile_blocks = 0;
+  offset_data.num_x_levels = static_cast<int>(num_x_tiles.size());
+  offset_data.num_y_levels = static_cast<int>(num_y_tiles.size());
+  switch (exr_header->tile_level_mode) {
+  case TINYEXR_TILE_ONE_LEVEL:
+  case TINYEXR_TILE_MIPMAP_LEVELS:
+    assert(offset_data.num_x_levels == offset_data.num_y_levels);
+    offset_data.offsets.resize(offset_data.num_x_levels);
+
+    for (unsigned int l = 0; l < offset_data.offsets.size(); ++l) {
+      offset_data.offsets[l].resize(num_y_tiles[l]);
+
+      for (unsigned int dy = 0; dy < offset_data.offsets[l].size(); ++dy) {
+        offset_data.offsets[l][dy].resize(num_x_tiles[l]);
+        num_tile_blocks += num_x_tiles[l];
+      }
+    }
+    break;
+
+  case TINYEXR_TILE_RIPMAP_LEVELS:
+
+    offset_data.offsets.resize(static_cast<size_t>(offset_data.num_x_levels) * static_cast<size_t>(offset_data.num_y_levels));
+
+    for (int ly = 0; ly < offset_data.num_y_levels; ++ly) {
+      for (int lx = 0; lx < offset_data.num_x_levels; ++lx) {
+        int l = ly * offset_data.num_x_levels + lx;
+        offset_data.offsets[l].resize(num_y_tiles[ly]);
+
+        for (size_t dy = 0; dy < offset_data.offsets[l].size(); ++dy) {
+          offset_data.offsets[l][dy].resize(num_x_tiles[lx]);
+          num_tile_blocks += num_x_tiles[lx];
+        }
+      }
+    }
+    break;
+
+  default:
+    assert(false);
+  }
+  return num_tile_blocks;
+}
+
+static bool IsAnyOffsetsAreInvalid(const OffsetData& offset_data) {
+  for (unsigned int l = 0; l < offset_data.offsets.size(); ++l)
+    for (unsigned int dy = 0; dy < offset_data.offsets[l].size(); ++dy)
+      for (unsigned int dx = 0; dx < offset_data.offsets[l][dy].size(); ++dx)
+        if (reinterpret_cast<const tinyexr::tinyexr_int64&>(offset_data.offsets[l][dy][dx]) <= 0)
+          return true;
+
+  return false;
+}
+
+static bool isValidTile(const EXRHeader* exr_header,
+                        const OffsetData& offset_data,
+                        int dx, int dy, int lx, int ly) {
+  if (lx < 0 || ly < 0 || dx < 0 || dy < 0) return false;
+  int num_x_levels = offset_data.num_x_levels;
+  int num_y_levels = offset_data.num_y_levels;
+  switch (exr_header->tile_level_mode) {
+  case TINYEXR_TILE_ONE_LEVEL:
+
+    if (lx == 0 &&
+        ly == 0 &&
+        offset_data.offsets.size() > 0 &&
+        offset_data.offsets[0].size() > static_cast<size_t>(dy) &&
+        offset_data.offsets[0][dy].size() > static_cast<size_t>(dx)) {
+      return true;
+    }
+
+    break;
+
+  case TINYEXR_TILE_MIPMAP_LEVELS:
+
+    if (lx < num_x_levels &&
+        ly < num_y_levels &&
+        offset_data.offsets.size() > static_cast<size_t>(lx) &&
+        offset_data.offsets[lx].size() > static_cast<size_t>(dy) &&
+        offset_data.offsets[lx][dy].size() > static_cast<size_t>(dx)) {
+      return true;
+    }
+
+    break;
+
+  case TINYEXR_TILE_RIPMAP_LEVELS:
+  {
+    size_t idx = static_cast<size_t>(lx) + static_cast<size_t>(ly)* static_cast<size_t>(num_x_levels);
+    if (lx < num_x_levels &&
+       ly < num_y_levels &&
+       (offset_data.offsets.size() > idx) &&
+       offset_data.offsets[idx].size() > static_cast<size_t>(dy) &&
+       offset_data.offsets[idx][dy].size() > static_cast<size_t>(dx)) {
+      return true;
+    }
+  }
+
+    break;
+
+  default:
+
+    return false;
+  }
+
+  return false;
+}
+
+static void ReconstructTileOffsets(OffsetData& offset_data,
+                                   const EXRHeader* exr_header,
+                                   const unsigned char* head, const unsigned char* marker, const size_t /*size*/,
+                                   bool isMultiPartFile,
+                                   bool isDeep) {
+  int numXLevels = offset_data.num_x_levels;
+  for (unsigned int l = 0; l < offset_data.offsets.size(); ++l) {
+    for (unsigned int dy = 0; dy < offset_data.offsets[l].size(); ++dy) {
+      for (unsigned int dx = 0; dx < offset_data.offsets[l][dy].size(); ++dx) {
+        tinyexr::tinyexr_uint64 tileOffset = marker - head;
+
+        if (isMultiPartFile) {
+          //int partNumber;
+          marker += sizeof(int);
+        }
+
+        int tileX;
+        memcpy(&tileX, marker, sizeof(int));
+        tinyexr::swap4(&tileX);
+        marker += sizeof(int);
+
+        int tileY;
+        memcpy(&tileY, marker, sizeof(int));
+        tinyexr::swap4(&tileY);
+        marker += sizeof(int);
+
+        int levelX;
+        memcpy(&levelX, marker, sizeof(int));
+        tinyexr::swap4(&levelX);
+        marker += sizeof(int);
+
+        int levelY;
+        memcpy(&levelY, marker, sizeof(int));
+        tinyexr::swap4(&levelY);
+        marker += sizeof(int);
+
+        if (isDeep) {
+          tinyexr::tinyexr_int64 packed_offset_table_size;
+          memcpy(&packed_offset_table_size, marker, sizeof(tinyexr::tinyexr_int64));
+          tinyexr::swap8(reinterpret_cast<tinyexr::tinyexr_uint64*>(&packed_offset_table_size));
+          marker += sizeof(tinyexr::tinyexr_int64);
+
+          tinyexr::tinyexr_int64 packed_sample_size;
+          memcpy(&packed_sample_size, marker, sizeof(tinyexr::tinyexr_int64));
+          tinyexr::swap8(reinterpret_cast<tinyexr::tinyexr_uint64*>(&packed_sample_size));
+          marker += sizeof(tinyexr::tinyexr_int64);
+
+          // next Int64 is unpacked sample size - skip that too
+          marker += packed_offset_table_size + packed_sample_size + 8;
+
+        } else {
+
+          int dataSize;
+          memcpy(&dataSize, marker, sizeof(int));
+          tinyexr::swap4(&dataSize);
+          marker += sizeof(int);
+          marker += dataSize;
+        }
+
+        if (!isValidTile(exr_header, offset_data,
+          tileX, tileY, levelX, levelY))
+          return;
+
+        int level_idx = LevelIndex(levelX, levelY, exr_header->tile_level_mode, numXLevels);
+        offset_data.offsets[level_idx][tileY][tileX] = tileOffset;
+      }
+    }
+  }
+}
+
+// marker output is also
+static int ReadOffsets(OffsetData& offset_data,
+                       const unsigned char* head,
+                       const unsigned char*& marker,
+                       const size_t size,
+                       const char** err) {
+  for (unsigned int l = 0; l < offset_data.offsets.size(); ++l) {
+    for (unsigned int dy = 0; dy < offset_data.offsets[l].size(); ++dy) {
+      for (unsigned int dx = 0; dx < offset_data.offsets[l][dy].size(); ++dx) {
+        tinyexr::tinyexr_uint64 offset;
+        if ((marker + sizeof(tinyexr_uint64)) >= (head + size)) {
+          tinyexr::SetErrorMessage("Insufficient data size in offset table.", err);
+          return TINYEXR_ERROR_INVALID_DATA;
+        }
+
+        memcpy(&offset, marker, sizeof(tinyexr::tinyexr_uint64));
+        tinyexr::swap8(&offset);
+        if (offset >= size) {
+          tinyexr::SetErrorMessage("Invalid offset value in DecodeEXRImage.", err);
+          return TINYEXR_ERROR_INVALID_DATA;
+        }
+        marker += sizeof(tinyexr::tinyexr_uint64);  // = 8
+        offset_data.offsets[l][dy][dx] = offset;
+      }
+    }
+  }
+  return TINYEXR_SUCCESS;
+}
+
+static int DecodeEXRImage(EXRImage *exr_image, const EXRHeader *exr_header,
+                          const unsigned char *head,
+                          const unsigned char *marker, const size_t size,
+                          const char **err) {
+  if (exr_image == NULL || exr_header == NULL || head == NULL ||
+      marker == NULL || (size <= tinyexr::kEXRVersionSize)) {
+    tinyexr::SetErrorMessage("Invalid argument for DecodeEXRImage().", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  int num_scanline_blocks = 1;
+  if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_ZIP) {
+    num_scanline_blocks = 16;
+  } else if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_PIZ) {
+    num_scanline_blocks = 32;
+  } else if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_ZFP) {
+    num_scanline_blocks = 16;
+  }
+
+  if (exr_header->data_window.max_x < exr_header->data_window.min_x ||
+      exr_header->data_window.max_x - exr_header->data_window.min_x ==
+          std::numeric_limits<int>::max()) {
+    // Issue 63
+    tinyexr::SetErrorMessage("Invalid data width value", err);
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+  int data_width =
+      exr_header->data_window.max_x - exr_header->data_window.min_x + 1;
+
+  if (exr_header->data_window.max_y < exr_header->data_window.min_y ||
+      exr_header->data_window.max_y - exr_header->data_window.min_y ==
+          std::numeric_limits<int>::max()) {
+    tinyexr::SetErrorMessage("Invalid data height value", err);
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+  int data_height =
+      exr_header->data_window.max_y - exr_header->data_window.min_y + 1;
+
+  // Do not allow too large data_width and data_height. header invalid?
+  {
+    if (data_width > TINYEXR_DIMENSION_THRESHOLD) {
+      tinyexr::SetErrorMessage("data width too large.", err);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+    if (data_height > TINYEXR_DIMENSION_THRESHOLD) {
+      tinyexr::SetErrorMessage("data height too large.", err);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+  }
+
+  if (exr_header->tiled) {
+    if (exr_header->tile_size_x > TINYEXR_DIMENSION_THRESHOLD) {
+      tinyexr::SetErrorMessage("tile width too large.", err);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+    if (exr_header->tile_size_y > TINYEXR_DIMENSION_THRESHOLD) {
+      tinyexr::SetErrorMessage("tile height too large.", err);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+  }
+
+  // Read offset tables.
+  OffsetData offset_data;
+  size_t num_blocks = 0;
+  // For a multi-resolution image, the size of the offset table will be calculated from the other attributes of the header.
+  // If chunk_count > 0 then chunk_count must be equal to the calculated tile count.
+  if (exr_header->tiled) {
+    {
+      std::vector<int> num_x_tiles, num_y_tiles;
+      PrecalculateTileInfo(num_x_tiles, num_y_tiles, exr_header);
+      num_blocks = InitTileOffsets(offset_data, exr_header, num_x_tiles, num_y_tiles);
+      if (exr_header->chunk_count > 0) {
+        if (exr_header->chunk_count != static_cast<int>(num_blocks)) {
+          tinyexr::SetErrorMessage("Invalid offset table size.", err);
+          return TINYEXR_ERROR_INVALID_DATA;
+        }
+      }
+    }
+
+    int ret = ReadOffsets(offset_data, head, marker, size, err);
+    if (ret != TINYEXR_SUCCESS) return ret;
+    if (IsAnyOffsetsAreInvalid(offset_data)) {
+      ReconstructTileOffsets(offset_data, exr_header,
+        head, marker, size,
+        exr_header->multipart, exr_header->non_image);
+    }
+  } else if (exr_header->chunk_count > 0) {
+    // Use `chunkCount` attribute.
+    num_blocks = static_cast<size_t>(exr_header->chunk_count);
+    InitSingleResolutionOffsets(offset_data, num_blocks);
+  } else {
+    num_blocks = static_cast<size_t>(data_height) /
+      static_cast<size_t>(num_scanline_blocks);
+    if (num_blocks * static_cast<size_t>(num_scanline_blocks) <
+      static_cast<size_t>(data_height)) {
+      num_blocks++;
+    }
+
+    InitSingleResolutionOffsets(offset_data, num_blocks);
+  }
+
+  if (!exr_header->tiled) {
+    std::vector<tinyexr::tinyexr_uint64>& offsets = offset_data.offsets[0][0];
+    for (size_t y = 0; y < num_blocks; y++) {
+      tinyexr::tinyexr_uint64 offset;
+      // Issue #81
+      if ((marker + sizeof(tinyexr_uint64)) >= (head + size)) {
+        tinyexr::SetErrorMessage("Insufficient data size in offset table.", err);
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+
+      memcpy(&offset, marker, sizeof(tinyexr::tinyexr_uint64));
+      tinyexr::swap8(&offset);
+      if (offset >= size) {
+        tinyexr::SetErrorMessage("Invalid offset value in DecodeEXRImage.", err);
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+      marker += sizeof(tinyexr::tinyexr_uint64);  // = 8
+      offsets[y] = offset;
+    }
+
+    // If line offsets are invalid, we try to reconstruct it.
+    // See OpenEXR/IlmImf/ImfScanLineInputFile.cpp::readLineOffsets() for details.
+    for (size_t y = 0; y < num_blocks; y++) {
+      if (offsets[y] <= 0) {
+        // TODO(syoyo) Report as warning?
+        // if (err) {
+        //  stringstream ss;
+        //  ss << "Incomplete lineOffsets." << std::endl;
+        //  (*err) += ss.str();
+        //}
+        bool ret =
+          ReconstructLineOffsets(&offsets, num_blocks, head, marker, size);
+        if (ret) {
+          // OK
+          break;
+        } else {
+          tinyexr::SetErrorMessage(
+            "Cannot reconstruct lineOffset table in DecodeEXRImage.", err);
+          return TINYEXR_ERROR_INVALID_DATA;
+        }
+      }
+    }
+  }
+
+  {
+    std::string e;
+    int ret = DecodeChunk(exr_image, exr_header, offset_data, head, size, &e);
+
+    if (ret != TINYEXR_SUCCESS) {
+      if (!e.empty()) {
+        tinyexr::SetErrorMessage(e, err);
+      }
+
+#if 1
+      FreeEXRImage(exr_image);
+#else
+      // release memory(if exists)
+      if ((exr_header->num_channels > 0) && exr_image && exr_image->images) {
+        for (size_t c = 0; c < size_t(exr_header->num_channels); c++) {
+          if (exr_image->images[c]) {
+            free(exr_image->images[c]);
+            exr_image->images[c] = NULL;
+          }
+        }
+        free(exr_image->images);
+        exr_image->images = NULL;
+      }
+#endif
+    }
+
+    return ret;
+  }
+}
+
+static void GetLayers(const EXRHeader &exr_header,
+                      std::vector<std::string> &layer_names) {
+  // Naive implementation
+  // Group channels by layers
+  // go over all channel names, split by periods
+  // collect unique names
+  layer_names.clear();
+  for (int c = 0; c < exr_header.num_channels; c++) {
+    std::string full_name(exr_header.channels[c].name);
+    const size_t pos = full_name.find_last_of('.');
+    if (pos != std::string::npos && pos != 0 && pos + 1 < full_name.size()) {
+      full_name.erase(pos);
+      if (std::find(layer_names.begin(), layer_names.end(), full_name) ==
+          layer_names.end())
+        layer_names.push_back(full_name);
+    }
+  }
+}
+
+struct LayerChannel {
+  explicit LayerChannel(size_t i, std::string n) : index(i), name(n) {}
+  size_t index;
+  std::string name;
+};
+
+static void ChannelsInLayer(const EXRHeader &exr_header,
+                            const std::string &layer_name,
+                            std::vector<LayerChannel> &channels) {
+  channels.clear();
+  for (int c = 0; c < exr_header.num_channels; c++) {
+    std::string ch_name(exr_header.channels[c].name);
+    if (layer_name.empty()) {
+      const size_t pos = ch_name.find_last_of('.');
+      if (pos != std::string::npos && pos < ch_name.size()) {
+        ch_name = ch_name.substr(pos + 1);
+      }
+    } else {
+      const size_t pos = ch_name.find(layer_name + '.');
+      if (pos == std::string::npos) continue;
+      if (pos == 0) {
+        ch_name = ch_name.substr(layer_name.size() + 1);
+      }
+    }
+    LayerChannel ch(size_t(c), ch_name);
+    channels.push_back(ch);
+  }
+}
+
+}  // namespace tinyexr
+
+int EXRLayers(const char *filename, const char **layer_names[], int *num_layers,
+              const char **err) {
+  EXRVersion exr_version;
+  EXRHeader exr_header;
+  InitEXRHeader(&exr_header);
+
+  {
+    int ret = ParseEXRVersionFromFile(&exr_version, filename);
+    if (ret != TINYEXR_SUCCESS) {
+      tinyexr::SetErrorMessage("Invalid EXR header.", err);
+      return ret;
+    }
+
+    if (exr_version.multipart || exr_version.non_image) {
+      tinyexr::SetErrorMessage(
+          "Loading multipart or DeepImage is not supported  in LoadEXR() API",
+          err);
+      return TINYEXR_ERROR_INVALID_DATA;  // @fixme.
+    }
+  }
+
+  int ret = ParseEXRHeaderFromFile(&exr_header, &exr_version, filename, err);
+  if (ret != TINYEXR_SUCCESS) {
+    FreeEXRHeader(&exr_header);
+    return ret;
+  }
+
+  std::vector<std::string> layer_vec;
+  tinyexr::GetLayers(exr_header, layer_vec);
+
+  (*num_layers) = int(layer_vec.size());
+  (*layer_names) = static_cast<const char **>(
+      malloc(sizeof(const char *) * static_cast<size_t>(layer_vec.size())));
+  for (size_t c = 0; c < static_cast<size_t>(layer_vec.size()); c++) {
+#ifdef _MSC_VER
+    (*layer_names)[c] = _strdup(layer_vec[c].c_str());
+#else
+    (*layer_names)[c] = strdup(layer_vec[c].c_str());
+#endif
+  }
+
+  FreeEXRHeader(&exr_header);
+  return TINYEXR_SUCCESS;
+}
+
+int LoadEXR(float **out_rgba, int *width, int *height, const char *filename,
+            const char **err) {
+  return LoadEXRWithLayer(out_rgba, width, height, filename,
+                          /* layername */ NULL, err);
+}
+
+int LoadEXRWithLayer(float **out_rgba, int *width, int *height,
+                     const char *filename, const char *layername,
+                     const char **err) {
+  if (out_rgba == NULL) {
+    tinyexr::SetErrorMessage("Invalid argument for LoadEXR()", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  EXRVersion exr_version;
+  EXRImage exr_image;
+  EXRHeader exr_header;
+  InitEXRHeader(&exr_header);
+  InitEXRImage(&exr_image);
+
+  {
+    int ret = ParseEXRVersionFromFile(&exr_version, filename);
+    if (ret != TINYEXR_SUCCESS) {
+      std::stringstream ss;
+      ss << "Failed to open EXR file or read version info from EXR file. code("
+         << ret << ")";
+      tinyexr::SetErrorMessage(ss.str(), err);
+      return ret;
+    }
+
+    if (exr_version.multipart || exr_version.non_image) {
+      tinyexr::SetErrorMessage(
+          "Loading multipart or DeepImage is not supported  in LoadEXR() API",
+          err);
+      return TINYEXR_ERROR_INVALID_DATA;  // @fixme.
+    }
+  }
+
+  {
+    int ret = ParseEXRHeaderFromFile(&exr_header, &exr_version, filename, err);
+    if (ret != TINYEXR_SUCCESS) {
+      FreeEXRHeader(&exr_header);
+      return ret;
+    }
+  }
+
+  // Read HALF channel as FLOAT.
+  for (int i = 0; i < exr_header.num_channels; i++) {
+    if (exr_header.pixel_types[i] == TINYEXR_PIXELTYPE_HALF) {
+      exr_header.requested_pixel_types[i] = TINYEXR_PIXELTYPE_FLOAT;
+    }
+  }
+
+  // TODO: Probably limit loading to layers (channels) selected by layer index
+  {
+    int ret = LoadEXRImageFromFile(&exr_image, &exr_header, filename, err);
+    if (ret != TINYEXR_SUCCESS) {
+      FreeEXRHeader(&exr_header);
+      return ret;
+    }
+  }
+
+  // RGBA
+  int idxR = -1;
+  int idxG = -1;
+  int idxB = -1;
+  int idxA = -1;
+
+  std::vector<std::string> layer_names;
+  tinyexr::GetLayers(exr_header, layer_names);
+
+  std::vector<tinyexr::LayerChannel> channels;
+  tinyexr::ChannelsInLayer(
+      exr_header, layername == NULL ? "" : std::string(layername), channels);
+
+  if (channels.size() < 1) {
+    tinyexr::SetErrorMessage("Layer Not Found", err);
+    FreeEXRHeader(&exr_header);
+    FreeEXRImage(&exr_image);
+    return TINYEXR_ERROR_LAYER_NOT_FOUND;
+  }
+
+  size_t ch_count = channels.size() < 4 ? channels.size() : 4;
+  for (size_t c = 0; c < ch_count; c++) {
+    const tinyexr::LayerChannel &ch = channels[c];
+
+    if (ch.name == "R") {
+      idxR = int(ch.index);
+    } else if (ch.name == "G") {
+      idxG = int(ch.index);
+    } else if (ch.name == "B") {
+      idxB = int(ch.index);
+    } else if (ch.name == "A") {
+      idxA = int(ch.index);
+    }
+  }
+
+  if (channels.size() == 1) {
+    int chIdx = int(channels.front().index);
+    // Grayscale channel only.
+
+    (*out_rgba) = reinterpret_cast<float *>(
+        malloc(4 * sizeof(float) * static_cast<size_t>(exr_image.width) *
+               static_cast<size_t>(exr_image.height)));
+
+    if (exr_header.tiled) {
+      for (int it = 0; it < exr_image.num_tiles; it++) {
+        for (int j = 0; j < exr_header.tile_size_y; j++) {
+          for (int i = 0; i < exr_header.tile_size_x; i++) {
+            const int ii = exr_image.tiles[it].offset_x *
+                               static_cast<int>(exr_header.tile_size_x) +
+                           i;
+            const int jj = exr_image.tiles[it].offset_y *
+                               static_cast<int>(exr_header.tile_size_y) +
+                           j;
+            const int idx = ii + jj * static_cast<int>(exr_image.width);
+
+            // out of region check.
+            if (ii >= exr_image.width) {
+              continue;
+            }
+            if (jj >= exr_image.height) {
+              continue;
+            }
+            const int srcIdx = i + j * exr_header.tile_size_x;
+            unsigned char **src = exr_image.tiles[it].images;
+            (*out_rgba)[4 * idx + 0] =
+                reinterpret_cast<float **>(src)[chIdx][srcIdx];
+            (*out_rgba)[4 * idx + 1] =
+                reinterpret_cast<float **>(src)[chIdx][srcIdx];
+            (*out_rgba)[4 * idx + 2] =
+                reinterpret_cast<float **>(src)[chIdx][srcIdx];
+            (*out_rgba)[4 * idx + 3] =
+                reinterpret_cast<float **>(src)[chIdx][srcIdx];
+          }
+        }
+      }
+    } else {
+      for (int i = 0; i < exr_image.width * exr_image.height; i++) {
+        const float val =
+            reinterpret_cast<float **>(exr_image.images)[chIdx][i];
+        (*out_rgba)[4 * i + 0] = val;
+        (*out_rgba)[4 * i + 1] = val;
+        (*out_rgba)[4 * i + 2] = val;
+        (*out_rgba)[4 * i + 3] = val;
+      }
+    }
+  } else {
+    // Assume RGB(A)
+
+    if (idxR == -1) {
+      tinyexr::SetErrorMessage("R channel not found", err);
+
+      FreeEXRHeader(&exr_header);
+      FreeEXRImage(&exr_image);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    if (idxG == -1) {
+      tinyexr::SetErrorMessage("G channel not found", err);
+      FreeEXRHeader(&exr_header);
+      FreeEXRImage(&exr_image);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    if (idxB == -1) {
+      tinyexr::SetErrorMessage("B channel not found", err);
+      FreeEXRHeader(&exr_header);
+      FreeEXRImage(&exr_image);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    (*out_rgba) = reinterpret_cast<float *>(
+        malloc(4 * sizeof(float) * static_cast<size_t>(exr_image.width) *
+               static_cast<size_t>(exr_image.height)));
+    if (exr_header.tiled) {
+      for (int it = 0; it < exr_image.num_tiles; it++) {
+        for (int j = 0; j < exr_header.tile_size_y; j++) {
+          for (int i = 0; i < exr_header.tile_size_x; i++) {
+            const int ii =
+                exr_image.tiles[it].offset_x * exr_header.tile_size_x + i;
+            const int jj =
+                exr_image.tiles[it].offset_y * exr_header.tile_size_y + j;
+            const int idx = ii + jj * exr_image.width;
+
+            // out of region check.
+            if (ii >= exr_image.width) {
+              continue;
+            }
+            if (jj >= exr_image.height) {
+              continue;
+            }
+            const int srcIdx = i + j * exr_header.tile_size_x;
+            unsigned char **src = exr_image.tiles[it].images;
+            (*out_rgba)[4 * idx + 0] =
+                reinterpret_cast<float **>(src)[idxR][srcIdx];
+            (*out_rgba)[4 * idx + 1] =
+                reinterpret_cast<float **>(src)[idxG][srcIdx];
+            (*out_rgba)[4 * idx + 2] =
+                reinterpret_cast<float **>(src)[idxB][srcIdx];
+            if (idxA != -1) {
+              (*out_rgba)[4 * idx + 3] =
+                  reinterpret_cast<float **>(src)[idxA][srcIdx];
+            } else {
+              (*out_rgba)[4 * idx + 3] = 1.0;
+            }
+          }
+        }
+      }
+    } else {
+      for (int i = 0; i < exr_image.width * exr_image.height; i++) {
+        (*out_rgba)[4 * i + 0] =
+            reinterpret_cast<float **>(exr_image.images)[idxR][i];
+        (*out_rgba)[4 * i + 1] =
+            reinterpret_cast<float **>(exr_image.images)[idxG][i];
+        (*out_rgba)[4 * i + 2] =
+            reinterpret_cast<float **>(exr_image.images)[idxB][i];
+        if (idxA != -1) {
+          (*out_rgba)[4 * i + 3] =
+              reinterpret_cast<float **>(exr_image.images)[idxA][i];
+        } else {
+          (*out_rgba)[4 * i + 3] = 1.0;
+        }
+      }
+    }
+  }
+
+  (*width) = exr_image.width;
+  (*height) = exr_image.height;
+
+  FreeEXRHeader(&exr_header);
+  FreeEXRImage(&exr_image);
+
+  return TINYEXR_SUCCESS;
+}
+
+int IsEXR(const char *filename) {
+  EXRVersion exr_version;
+
+  int ret = ParseEXRVersionFromFile(&exr_version, filename);
+  if (ret != TINYEXR_SUCCESS) {
+    return ret;
+  }
+
+  return TINYEXR_SUCCESS;
+}
+
+int ParseEXRHeaderFromMemory(EXRHeader *exr_header, const EXRVersion *version,
+                             const unsigned char *memory, size_t size,
+                             const char **err) {
+  if (memory == NULL || exr_header == NULL) {
+    tinyexr::SetErrorMessage(
+        "Invalid argument. `memory` or `exr_header` argument is null in "
+        "ParseEXRHeaderFromMemory()",
+        err);
+
+    // Invalid argument
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  if (size < tinyexr::kEXRVersionSize) {
+    tinyexr::SetErrorMessage("Insufficient header/data size.\n", err);
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+
+  const unsigned char *marker = memory + tinyexr::kEXRVersionSize;
+  size_t marker_size = size - tinyexr::kEXRVersionSize;
+
+  tinyexr::HeaderInfo info;
+  info.clear();
+
+  int ret;
+  {
+    std::string err_str;
+    ret = ParseEXRHeader(&info, NULL, version, &err_str, marker, marker_size);
+
+    if (ret != TINYEXR_SUCCESS) {
+      if (err && !err_str.empty()) {
+        tinyexr::SetErrorMessage(err_str, err);
+      }
+    }
+  }
+
+  {
+    std::string warn;
+    std::string err_str;
+
+    if (!ConvertHeader(exr_header, info, &warn, &err_str)) {
+      if (err && !err_str.empty()) {
+        tinyexr::SetErrorMessage(err_str, err);
+      }
+      ret = TINYEXR_ERROR_INVALID_HEADER;
+    }
+  }
+
+  exr_header->multipart = version->multipart ? 1 : 0;
+  exr_header->non_image = version->non_image ? 1 : 0;
+
+  return ret;
+}
+
+int LoadEXRFromMemory(float **out_rgba, int *width, int *height,
+                      const unsigned char *memory, size_t size,
+                      const char **err) {
+  if (out_rgba == NULL || memory == NULL) {
+    tinyexr::SetErrorMessage("Invalid argument for LoadEXRFromMemory", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  EXRVersion exr_version;
+  EXRImage exr_image;
+  EXRHeader exr_header;
+
+  InitEXRHeader(&exr_header);
+
+  int ret = ParseEXRVersionFromMemory(&exr_version, memory, size);
+  if (ret != TINYEXR_SUCCESS) {
+    std::stringstream ss;
+    ss << "Failed to parse EXR version. code(" << ret << ")";
+    tinyexr::SetErrorMessage(ss.str(), err);
+    return ret;
+  }
+
+  ret = ParseEXRHeaderFromMemory(&exr_header, &exr_version, memory, size, err);
+  if (ret != TINYEXR_SUCCESS) {
+    return ret;
+  }
+
+  // Read HALF channel as FLOAT.
+  for (int i = 0; i < exr_header.num_channels; i++) {
+    if (exr_header.pixel_types[i] == TINYEXR_PIXELTYPE_HALF) {
+      exr_header.requested_pixel_types[i] = TINYEXR_PIXELTYPE_FLOAT;
+    }
+  }
+
+  InitEXRImage(&exr_image);
+  ret = LoadEXRImageFromMemory(&exr_image, &exr_header, memory, size, err);
+  if (ret != TINYEXR_SUCCESS) {
+    return ret;
+  }
+
+  // RGBA
+  int idxR = -1;
+  int idxG = -1;
+  int idxB = -1;
+  int idxA = -1;
+  for (int c = 0; c < exr_header.num_channels; c++) {
+    if (strcmp(exr_header.channels[c].name, "R") == 0) {
+      idxR = c;
+    } else if (strcmp(exr_header.channels[c].name, "G") == 0) {
+      idxG = c;
+    } else if (strcmp(exr_header.channels[c].name, "B") == 0) {
+      idxB = c;
+    } else if (strcmp(exr_header.channels[c].name, "A") == 0) {
+      idxA = c;
+    }
+  }
+
+  // TODO(syoyo): Refactor removing same code as used in LoadEXR().
+  if (exr_header.num_channels == 1) {
+    // Grayscale channel only.
+
+    (*out_rgba) = reinterpret_cast<float *>(
+        malloc(4 * sizeof(float) * static_cast<size_t>(exr_image.width) *
+               static_cast<size_t>(exr_image.height)));
+
+    if (exr_header.tiled) {
+      for (int it = 0; it < exr_image.num_tiles; it++) {
+        for (int j = 0; j < exr_header.tile_size_y; j++) {
+          for (int i = 0; i < exr_header.tile_size_x; i++) {
+            const int ii =
+                exr_image.tiles[it].offset_x * exr_header.tile_size_x + i;
+            const int jj =
+                exr_image.tiles[it].offset_y * exr_header.tile_size_y + j;
+            const int idx = ii + jj * exr_image.width;
+
+            // out of region check.
+            if (ii >= exr_image.width) {
+              continue;
+            }
+            if (jj >= exr_image.height) {
+              continue;
+            }
+            const int srcIdx = i + j * exr_header.tile_size_x;
+            unsigned char **src = exr_image.tiles[it].images;
+            (*out_rgba)[4 * idx + 0] =
+                reinterpret_cast<float **>(src)[0][srcIdx];
+            (*out_rgba)[4 * idx + 1] =
+                reinterpret_cast<float **>(src)[0][srcIdx];
+            (*out_rgba)[4 * idx + 2] =
+                reinterpret_cast<float **>(src)[0][srcIdx];
+            (*out_rgba)[4 * idx + 3] =
+                reinterpret_cast<float **>(src)[0][srcIdx];
+          }
+        }
+      }
+    } else {
+      for (int i = 0; i < exr_image.width * exr_image.height; i++) {
+        const float val = reinterpret_cast<float **>(exr_image.images)[0][i];
+        (*out_rgba)[4 * i + 0] = val;
+        (*out_rgba)[4 * i + 1] = val;
+        (*out_rgba)[4 * i + 2] = val;
+        (*out_rgba)[4 * i + 3] = val;
+      }
+    }
+
+  } else {
+    // TODO(syoyo): Support non RGBA image.
+
+    if (idxR == -1) {
+      tinyexr::SetErrorMessage("R channel not found", err);
+
+      // @todo { free exr_image }
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    if (idxG == -1) {
+      tinyexr::SetErrorMessage("G channel not found", err);
+      // @todo { free exr_image }
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    if (idxB == -1) {
+      tinyexr::SetErrorMessage("B channel not found", err);
+      // @todo { free exr_image }
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    (*out_rgba) = reinterpret_cast<float *>(
+        malloc(4 * sizeof(float) * static_cast<size_t>(exr_image.width) *
+               static_cast<size_t>(exr_image.height)));
+
+    if (exr_header.tiled) {
+      for (int it = 0; it < exr_image.num_tiles; it++) {
+        for (int j = 0; j < exr_header.tile_size_y; j++)
+          for (int i = 0; i < exr_header.tile_size_x; i++) {
+            const int ii =
+                exr_image.tiles[it].offset_x * exr_header.tile_size_x + i;
+            const int jj =
+                exr_image.tiles[it].offset_y * exr_header.tile_size_y + j;
+            const int idx = ii + jj * exr_image.width;
+
+            // out of region check.
+            if (ii >= exr_image.width) {
+              continue;
+            }
+            if (jj >= exr_image.height) {
+              continue;
+            }
+            const int srcIdx = i + j * exr_header.tile_size_x;
+            unsigned char **src = exr_image.tiles[it].images;
+            (*out_rgba)[4 * idx + 0] =
+                reinterpret_cast<float **>(src)[idxR][srcIdx];
+            (*out_rgba)[4 * idx + 1] =
+                reinterpret_cast<float **>(src)[idxG][srcIdx];
+            (*out_rgba)[4 * idx + 2] =
+                reinterpret_cast<float **>(src)[idxB][srcIdx];
+            if (idxA != -1) {
+              (*out_rgba)[4 * idx + 3] =
+                  reinterpret_cast<float **>(src)[idxA][srcIdx];
+            } else {
+              (*out_rgba)[4 * idx + 3] = 1.0;
+            }
+          }
+      }
+    } else {
+      for (int i = 0; i < exr_image.width * exr_image.height; i++) {
+        (*out_rgba)[4 * i + 0] =
+            reinterpret_cast<float **>(exr_image.images)[idxR][i];
+        (*out_rgba)[4 * i + 1] =
+            reinterpret_cast<float **>(exr_image.images)[idxG][i];
+        (*out_rgba)[4 * i + 2] =
+            reinterpret_cast<float **>(exr_image.images)[idxB][i];
+        if (idxA != -1) {
+          (*out_rgba)[4 * i + 3] =
+              reinterpret_cast<float **>(exr_image.images)[idxA][i];
+        } else {
+          (*out_rgba)[4 * i + 3] = 1.0;
+        }
+      }
+    }
+  }
+
+  (*width) = exr_image.width;
+  (*height) = exr_image.height;
+
+  FreeEXRHeader(&exr_header);
+  FreeEXRImage(&exr_image);
+
+  return TINYEXR_SUCCESS;
+}
+
+int LoadEXRImageFromFile(EXRImage *exr_image, const EXRHeader *exr_header,
+                         const char *filename, const char **err) {
+  if (exr_image == NULL) {
+    tinyexr::SetErrorMessage("Invalid argument for LoadEXRImageFromFile", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  FILE *fp = NULL;
+#ifdef _WIN32
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang.
+  errno_t errcode =
+      _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"rb");
+  if (errcode != 0) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    // TODO(syoyo): return wfopen_s erro code
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "rb");
+#endif
+#else
+  fp = fopen(filename, "rb");
+#endif
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+
+  size_t filesize;
+  // Compute size
+  fseek(fp, 0, SEEK_END);
+  filesize = static_cast<size_t>(ftell(fp));
+  fseek(fp, 0, SEEK_SET);
+
+  if (filesize < 16) {
+    tinyexr::SetErrorMessage("File size too short " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_INVALID_FILE;
+  }
+
+  std::vector<unsigned char> buf(filesize);  // @todo { use mmap }
+  {
+    size_t ret;
+    ret = fread(&buf[0], 1, filesize, fp);
+    assert(ret == filesize);
+    fclose(fp);
+    (void)ret;
+  }
+
+  return LoadEXRImageFromMemory(exr_image, exr_header, &buf.at(0), filesize,
+                                err);
+}
+
+int LoadEXRImageFromMemory(EXRImage *exr_image, const EXRHeader *exr_header,
+                           const unsigned char *memory, const size_t size,
+                           const char **err) {
+  if (exr_image == NULL || memory == NULL ||
+      (size < tinyexr::kEXRVersionSize)) {
+    tinyexr::SetErrorMessage("Invalid argument for LoadEXRImageFromMemory",
+                             err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  if (exr_header->header_len == 0) {
+    tinyexr::SetErrorMessage("EXRHeader variable is not initialized.", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  const unsigned char *head = memory;
+  const unsigned char *marker = reinterpret_cast<const unsigned char *>(
+      memory + exr_header->header_len +
+      8);  // +8 for magic number + version header.
+  return tinyexr::DecodeEXRImage(exr_image, exr_header, head, marker, size,
+                                 err);
+}
+
+namespace tinyexr
+{
+
+// out_data must be allocated initially with the block-header size
+// of the current image(-part) type
+static bool EncodePixelData(/* out */ std::vector<unsigned char>& out_data,                         
+                            const unsigned char* const* images,
+                            int compression_type,
+                            int /*line_order*/,
+                            int width, // for tiled : tile.width
+                            int /*height*/, // for tiled : header.tile_size_y
+                            int x_stride, // for tiled : header.tile_size_x
+                            int line_no, // for tiled : 0
+                            int num_lines, // for tiled : tile.height
+                            size_t pixel_data_size,
+                            const std::vector<ChannelInfo>& channels,
+                            const std::vector<size_t>& channel_offset_list,
+                            const void* compression_param = 0) // zfp compression param
+{
+  size_t buf_size = static_cast<size_t>(width) *
+                  static_cast<size_t>(num_lines) *
+                  static_cast<size_t>(pixel_data_size);
+  //int last2bit = (buf_size & 3);
+  // buf_size must be multiple of four
+  //if(last2bit) buf_size += 4 - last2bit;
+  std::vector<unsigned char> buf(buf_size);
+
+  size_t start_y = static_cast<size_t>(line_no);
+  for (size_t c = 0; c < channels.size(); c++) {
+    if (channels[c].pixel_type == TINYEXR_PIXELTYPE_HALF) {
+      if (channels[c].requested_pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+        for (int y = 0; y < num_lines; y++) {
+          // Assume increasing Y
+          float *line_ptr = reinterpret_cast<float *>(&buf.at(
+            static_cast<size_t>(pixel_data_size * y * width) +
+            channel_offset_list[c] *
+            static_cast<size_t>(width)));
+          for (int x = 0; x < width; x++) {
+            tinyexr::FP16 h16;
+            h16.u = reinterpret_cast<const unsigned short * const *>(
+              images)[c][(y + start_y) * x_stride + x];
+
+            tinyexr::FP32 f32 = half_to_float(h16);
+
+            tinyexr::swap4(&f32.f);
+
+            // line_ptr[x] = f32.f;
+            tinyexr::cpy4(line_ptr + x, &(f32.f));
+          }
+        }
+      } else if (channels[c].requested_pixel_type == TINYEXR_PIXELTYPE_HALF) {
+        for (int y = 0; y < num_lines; y++) {
+          // Assume increasing Y
+          unsigned short *line_ptr = reinterpret_cast<unsigned short *>(
+            &buf.at(static_cast<size_t>(pixel_data_size * y *
+                                        width) +
+                    channel_offset_list[c] *
+                    static_cast<size_t>(width)));
+          for (int x = 0; x < width; x++) {
+            unsigned short val = reinterpret_cast<const unsigned short * const *>(
+              images)[c][(y + start_y) * x_stride + x];
+
+            tinyexr::swap2(&val);
+
+            // line_ptr[x] = val;
+            tinyexr::cpy2(line_ptr + x, &val);
+          }
+        }
+      } else {
+        assert(0);
+      }
+
+    } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+      if (channels[c].requested_pixel_type == TINYEXR_PIXELTYPE_HALF) {
+        for (int y = 0; y < num_lines; y++) {
+          // Assume increasing Y
+          unsigned short *line_ptr = reinterpret_cast<unsigned short *>(
+            &buf.at(static_cast<size_t>(pixel_data_size * y *
+                                        width) +
+                    channel_offset_list[c] *
+                    static_cast<size_t>(width)));
+          for (int x = 0; x < width; x++) {
+            tinyexr::FP32 f32;
+            f32.f = reinterpret_cast<const float * const *>(
+              images)[c][(y + start_y) * x_stride + x];
+
+            tinyexr::FP16 h16;
+            h16 = float_to_half_full(f32);
+
+            tinyexr::swap2(reinterpret_cast<unsigned short *>(&h16.u));
+
+            // line_ptr[x] = h16.u;
+            tinyexr::cpy2(line_ptr + x, &(h16.u));
+          }
+        }
+      } else if (channels[c].requested_pixel_type == TINYEXR_PIXELTYPE_FLOAT) {
+        for (int y = 0; y < num_lines; y++) {
+          // Assume increasing Y
+          float *line_ptr = reinterpret_cast<float *>(&buf.at(
+            static_cast<size_t>(pixel_data_size * y * width) +
+            channel_offset_list[c] *
+            static_cast<size_t>(width)));
+          for (int x = 0; x < width; x++) {
+            float val = reinterpret_cast<const float * const *>(
+              images)[c][(y + start_y) * x_stride + x];
+
+            tinyexr::swap4(&val);
+
+            // line_ptr[x] = val;
+            tinyexr::cpy4(line_ptr + x, &val);
+          }
+        }
+      } else {
+        assert(0);
+      }
+    } else if (channels[c].pixel_type == TINYEXR_PIXELTYPE_UINT) {
+      for (int y = 0; y < num_lines; y++) {
+        // Assume increasing Y
+        unsigned int *line_ptr = reinterpret_cast<unsigned int *>(&buf.at(
+          static_cast<size_t>(pixel_data_size * y * width) +
+          channel_offset_list[c] * static_cast<size_t>(width)));
+        for (int x = 0; x < width; x++) {
+          unsigned int val = reinterpret_cast<const unsigned int * const *>(
+            images)[c][(y + start_y) * x_stride + x];
+
+          tinyexr::swap4(&val);
+
+          // line_ptr[x] = val;
+          tinyexr::cpy4(line_ptr + x, &val);
+        }
+      }
+    }
+  }
+
+  if (compression_type == TINYEXR_COMPRESSIONTYPE_NONE) {
+    // 4 byte: scan line
+    // 4 byte: data size
+    // ~     : pixel data(uncompressed)
+    out_data.insert(out_data.end(), buf.begin(), buf.end());
+
+  } else if ((compression_type == TINYEXR_COMPRESSIONTYPE_ZIPS) ||
+    (compression_type == TINYEXR_COMPRESSIONTYPE_ZIP)) {
+#if TINYEXR_USE_MINIZ
+    std::vector<unsigned char> block(mz_compressBound(
+      static_cast<unsigned long>(buf.size())));
+#else
+    std::vector<unsigned char> block(
+      compressBound(static_cast<uLong>(buf.size())));
+#endif
+    tinyexr::tinyexr_uint64 outSize = block.size();
+
+    tinyexr::CompressZip(&block.at(0), outSize,
+                         reinterpret_cast<const unsigned char *>(&buf.at(0)),
+                         static_cast<unsigned long>(buf.size()));
+
+    // 4 byte: scan line
+    // 4 byte: data size
+    // ~     : pixel data(compressed)
+    unsigned int data_len = static_cast<unsigned int>(outSize);  // truncate
+
+    out_data.insert(out_data.end(), block.begin(), block.begin() + data_len);
+
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_RLE) {
+    // (buf.size() * 3) / 2 would be enough.
+    std::vector<unsigned char> block((buf.size() * 3) / 2);
+
+    tinyexr::tinyexr_uint64 outSize = block.size();
+
+    tinyexr::CompressRle(&block.at(0), outSize,
+                         reinterpret_cast<const unsigned char *>(&buf.at(0)),
+                         static_cast<unsigned long>(buf.size()));
+
+    // 4 byte: scan line
+    // 4 byte: data size
+    // ~     : pixel data(compressed)
+    unsigned int data_len = static_cast<unsigned int>(outSize);  // truncate
+    out_data.insert(out_data.end(), block.begin(), block.begin() + data_len);
+
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_PIZ) {
+#if TINYEXR_USE_PIZ
+    unsigned int bufLen =
+      8192 + static_cast<unsigned int>(
+        2 * static_cast<unsigned int>(
+          buf.size()));  // @fixme { compute good bound. }
+    std::vector<unsigned char> block(bufLen);
+    unsigned int outSize = static_cast<unsigned int>(block.size());
+
+    CompressPiz(&block.at(0), &outSize,
+                reinterpret_cast<const unsigned char *>(&buf.at(0)),
+                buf.size(), channels, width, num_lines);
+
+    // 4 byte: scan line
+    // 4 byte: data size
+    // ~     : pixel data(compressed)
+    unsigned int data_len = outSize;
+    out_data.insert(out_data.end(), block.begin(), block.begin() + data_len);
+
+#else
+    assert(0);
+#endif
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_ZFP) {
+#if TINYEXR_USE_ZFP
+    const ZFPCompressionParam* zfp_compression_param = reinterpret_cast<const ZFPCompressionParam*>(compression_param);
+    std::vector<unsigned char> block;
+    unsigned int outSize;
+
+    tinyexr::CompressZfp(
+      &block, &outSize, reinterpret_cast<const float *>(&buf.at(0)),
+      width, num_lines, static_cast<int>(channels.size()), *zfp_compression_param);
+
+    // 4 byte: scan line
+    // 4 byte: data size
+    // ~     : pixel data(compressed)
+    unsigned int data_len = outSize;
+    out_data.insert(out_data.end(), block.begin(), block.begin() + data_len);
+
+#else
+    (void)compression_param;
+    assert(0);
+#endif
+  } else {
+    assert(0);
+    return false;
+  }
+
+  return true;
+}
+
+static int EncodeTiledLevel(const EXRImage* level_image, const EXRHeader* exr_header,
+                            const std::vector<tinyexr::ChannelInfo>& channels,
+                            std::vector<std::vector<unsigned char> >& data_list,
+                            size_t start_index, // for data_list
+                            int num_x_tiles, int num_y_tiles,
+                            const std::vector<size_t>& channel_offset_list,
+                            int pixel_data_size,
+                            const void* compression_param, // must be set if zfp compression is enabled
+                            std::string* err) {
+  int num_tiles = num_x_tiles * num_y_tiles;
+  assert(num_tiles == level_image->num_tiles);
+
+  if ((exr_header->tile_size_x > level_image->width || exr_header->tile_size_y > level_image->height) &&
+      level_image->level_x == 0 && level_image->level_y == 0) {
+      if (err) {
+        (*err) += "Failed to encode tile data.\n";
+    }
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+  std::atomic<bool> invalid_data(false);
+#else
+  bool invalid_data(false);
+#endif
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+  std::vector<std::thread> workers;
+  std::atomic<int> tile_count(0);
+
+  int num_threads = std::max(1, int(std::thread::hardware_concurrency()));
+  if (num_threads > int(num_tiles)) {
+    num_threads = int(num_tiles);
+  }
+
+  for (int t = 0; t < num_threads; t++) {
+    workers.emplace_back(std::thread([&]() {
+      int i = 0;
+      while ((i = tile_count++) < num_tiles) {
+
+#else
+  // Use signed int since some OpenMP compiler doesn't allow unsigned type for
+  // `parallel for`
+#if TINYEXR_USE_OPENMP
+#pragma omp parallel for
+#endif
+  for (int i = 0; i < num_tiles; i++) {
+
+#endif
+    size_t tile_idx = static_cast<size_t>(i);
+    size_t data_idx = tile_idx + start_index;
+
+    int x_tile = i % num_x_tiles;
+    int y_tile = i / num_x_tiles;
+
+    EXRTile& tile = level_image->tiles[tile_idx];
+ 
+    const unsigned char* const* images =
+      static_cast<const unsigned char* const*>(tile.images);
+
+    data_list[data_idx].resize(5*sizeof(int));
+    size_t data_header_size = data_list[data_idx].size();
+    bool ret = EncodePixelData(data_list[data_idx],                         
+                               images,
+                               exr_header->compression_type,
+                               0, // increasing y
+                               tile.width,
+                               exr_header->tile_size_y,
+                               exr_header->tile_size_x,
+                               0,
+                               tile.height,
+                               pixel_data_size,
+                               channels,
+                               channel_offset_list,
+                               compression_param);
+    if (!ret) {
+      invalid_data = true;
+      continue;
+    }
+    assert(data_list[data_idx].size() > data_header_size);
+    int data_len = static_cast<int>(data_list[data_idx].size() - data_header_size);
+    //tileX, tileY, levelX, levelY // pixel_data_size(int)
+    memcpy(&data_list[data_idx][0], &x_tile, sizeof(int));
+    memcpy(&data_list[data_idx][4], &y_tile, sizeof(int));
+    memcpy(&data_list[data_idx][8], &level_image->level_x, sizeof(int));
+    memcpy(&data_list[data_idx][12], &level_image->level_y, sizeof(int));
+    memcpy(&data_list[data_idx][16], &data_len, sizeof(int));
+
+    swap4(reinterpret_cast<int*>(&data_list[data_idx][0]));
+    swap4(reinterpret_cast<int*>(&data_list[data_idx][4]));
+    swap4(reinterpret_cast<int*>(&data_list[data_idx][8]));
+    swap4(reinterpret_cast<int*>(&data_list[data_idx][12]));
+    swap4(reinterpret_cast<int*>(&data_list[data_idx][16]));
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+  }
+}));
+    }
+
+    for (auto &t : workers) {
+      t.join();
+    }
+#else
+    }  // omp parallel
+#endif
+
+  if (invalid_data) {
+    if (err) {
+      (*err) += "Failed to encode tile data.\n";  
+    }
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+  return TINYEXR_SUCCESS;
+}
+
+static int NumScanlines(int compression_type) {
+  int num_scanlines = 1;
+  if (compression_type == TINYEXR_COMPRESSIONTYPE_ZIP) {
+    num_scanlines = 16;
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_PIZ) {
+    num_scanlines = 32;
+  } else if (compression_type == TINYEXR_COMPRESSIONTYPE_ZFP) {
+    num_scanlines = 16;
+  }
+  return num_scanlines;
+}
+
+static int EncodeChunk(const EXRImage* exr_image, const EXRHeader* exr_header,
+                       const std::vector<ChannelInfo>& channels,
+                       int num_blocks,
+                       tinyexr_uint64 chunk_offset, // starting offset of current chunk
+                       bool is_multipart,
+                       OffsetData& offset_data, // output block offsets, must be initialized
+                       std::vector<std::vector<unsigned char> >& data_list, // output
+                       tinyexr_uint64& total_size, // output: ending offset of current chunk
+                       std::string* err) {
+  int num_scanlines = NumScanlines(exr_header->compression_type);
+
+  data_list.resize(num_blocks);
+
+  std::vector<size_t> channel_offset_list(
+    static_cast<size_t>(exr_header->num_channels));
+
+  int pixel_data_size = 0;
+  {
+    size_t channel_offset = 0;
+    for (size_t c = 0; c < static_cast<size_t>(exr_header->num_channels); c++) {
+      channel_offset_list[c] = channel_offset;
+      if (channels[c].requested_pixel_type == TINYEXR_PIXELTYPE_HALF) {
+        pixel_data_size += sizeof(unsigned short);
+        channel_offset += sizeof(unsigned short);
+      } else if (channels[c].requested_pixel_type ==
+                 TINYEXR_PIXELTYPE_FLOAT) {
+        pixel_data_size += sizeof(float);
+        channel_offset += sizeof(float);
+      } else if (channels[c].requested_pixel_type == TINYEXR_PIXELTYPE_UINT) {
+        pixel_data_size += sizeof(unsigned int);
+        channel_offset += sizeof(unsigned int);
+      } else {
+        assert(0);
+      }
+    }
+  }
+
+  const void* compression_param = 0;
+#if TINYEXR_USE_ZFP
+  tinyexr::ZFPCompressionParam zfp_compression_param;
+
+  // Use ZFP compression parameter from custom attributes(if such a parameter
+  // exists)
+  {
+    std::string e;
+    bool ret = tinyexr::FindZFPCompressionParam(
+      &zfp_compression_param, exr_header->custom_attributes,
+      exr_header->num_custom_attributes, &e);
+
+    if (!ret) {
+      // Use predefined compression parameter.
+      zfp_compression_param.type = 0;
+      zfp_compression_param.rate = 2;
+    }
+    compression_param = &zfp_compression_param;
+  }
+#endif
+
+  tinyexr_uint64 offset = chunk_offset;
+  tinyexr_uint64 doffset = is_multipart ? 4u : 0u;
+
+  if (exr_image->tiles) {
+    const EXRImage* level_image = exr_image;
+    size_t block_idx = 0;
+    tinyexr::tinyexr_uint64 block_data_size = 0;
+    int num_levels = (exr_header->tile_level_mode != TINYEXR_TILE_RIPMAP_LEVELS) ?
+      offset_data.num_x_levels : (offset_data.num_x_levels * offset_data.num_y_levels);
+    for (int level_index = 0; level_index < num_levels; ++level_index) {
+      if (!level_image) {
+        if (err) {
+          (*err) += "Invalid number of tiled levels for EncodeChunk\n";
+        }
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+
+      int level_index_from_image = LevelIndex(level_image->level_x, level_image->level_y,
+                                    exr_header->tile_level_mode, offset_data.num_x_levels);
+      if (level_index_from_image != level_index) {
+        if (err) {
+          (*err) += "Incorrect level ordering in tiled image\n";
+        }
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+      int num_y_tiles = (int)offset_data.offsets[level_index].size();
+      assert(num_y_tiles);
+      int num_x_tiles = (int)offset_data.offsets[level_index][0].size();
+      assert(num_x_tiles);
+
+      std::string e;
+      int ret = EncodeTiledLevel(level_image,
+                                  exr_header,
+                                  channels,
+                                  data_list,
+                                  block_idx,
+                                  num_x_tiles,
+                                  num_y_tiles,
+                                  channel_offset_list,
+                                  pixel_data_size,
+                                  compression_param,
+                                  &e);
+      if (ret != TINYEXR_SUCCESS) {
+        if (!e.empty() && err) {
+          (*err) += e;
+        }
+        return ret;
+      }
+
+      for (size_t j = 0; j < static_cast<size_t>(num_y_tiles); ++j)
+        for (size_t i = 0; i < static_cast<size_t>(num_x_tiles); ++i) {
+          offset_data.offsets[level_index][j][i] = offset;
+          swap8(reinterpret_cast<tinyexr_uint64*>(&offset_data.offsets[level_index][j][i]));
+          offset += data_list[block_idx].size() + doffset;
+          block_data_size += data_list[block_idx].size();
+          ++block_idx;
+        }
+      level_image = level_image->next_level;
+    }
+    assert(static_cast<int>(block_idx) == num_blocks);
+    total_size = offset;
+  } else { // scanlines
+    std::vector<tinyexr::tinyexr_uint64>& offsets = offset_data.offsets[0][0];
+
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+    std::atomic<bool> invalid_data(false);
+    std::vector<std::thread> workers;
+    std::atomic<int> block_count(0);
+
+    int num_threads = std::min(std::max(1, int(std::thread::hardware_concurrency())), num_blocks);
+
+    for (int t = 0; t < num_threads; t++) {
+      workers.emplace_back(std::thread([&]() {
+        int i = 0;
+        while ((i = block_count++) < num_blocks) {
+
+#else
+    bool invalid_data(false);
+#if TINYEXR_USE_OPENMP
+#pragma omp parallel for
+#endif
+    for (int i = 0; i < num_blocks; i++) {
+
+#endif
+      int start_y = num_scanlines * i;
+      int end_Y = (std::min)(num_scanlines * (i + 1), exr_image->height);
+      int num_lines = end_Y - start_y;
+
+      const unsigned char* const* images =
+        static_cast<const unsigned char* const*>(exr_image->images);
+
+      data_list[i].resize(2*sizeof(int));
+      size_t data_header_size = data_list[i].size();
+
+      bool ret = EncodePixelData(data_list[i],                         
+                                 images,
+                                 exr_header->compression_type,
+                                 0, // increasing y
+                                 exr_image->width,
+                                 exr_image->height,
+                                 exr_image->width,
+                                 start_y,
+                                 num_lines,
+                                 pixel_data_size,
+                                 channels,
+                                 channel_offset_list,
+                                 compression_param);
+      if (!ret) {
+        invalid_data = true;
+        continue; // "break" cannot be used with OpenMP 
+      }
+      assert(data_list[i].size() > data_header_size);
+      int data_len = static_cast<int>(data_list[i].size() - data_header_size);
+      memcpy(&data_list[i][0], &start_y, sizeof(int));
+      memcpy(&data_list[i][4], &data_len, sizeof(int));
+
+      swap4(reinterpret_cast<int*>(&data_list[i][0]));
+      swap4(reinterpret_cast<int*>(&data_list[i][4]));
+#if TINYEXR_HAS_CXX11 && (TINYEXR_USE_THREAD > 0)
+        }
+                                       }));
+    }
+
+    for (auto &t : workers) {
+      t.join();
+    }
+#else
+    }  // omp parallel
+#endif
+
+    if (invalid_data) {
+      if (err) {
+        (*err) += "Failed to encode scanline data.\n";
+      }
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    for (size_t i = 0; i < static_cast<size_t>(num_blocks); i++) {
+      offsets[i] = offset;
+      tinyexr::swap8(reinterpret_cast<tinyexr::tinyexr_uint64 *>(&offsets[i]));
+      offset += data_list[i].size() + doffset;
+    }
+
+    total_size = static_cast<size_t>(offset);
+  }
+  return TINYEXR_SUCCESS;
+}
+
+// can save a single or multi-part image (no deep* formats)
+static size_t SaveEXRNPartImageToMemory(const EXRImage* exr_images,
+                                        const EXRHeader** exr_headers,
+                                        unsigned int num_parts,
+                                        unsigned char** memory_out, const char** err) {
+  if (exr_images == NULL || exr_headers == NULL || num_parts == 0 ||
+      memory_out == NULL) {
+    SetErrorMessage("Invalid argument for SaveEXRNPartImageToMemory",
+                    err);
+    return 0;
+  }
+  {
+    for (unsigned int i = 0; i < num_parts; ++i) {
+      if (exr_headers[i]->compression_type < 0) {
+        SetErrorMessage("Invalid argument for SaveEXRNPartImageToMemory",
+                        err);
+        return 0;
+      }
+#if !TINYEXR_USE_PIZ
+      if (exr_headers[i]->compression_type == TINYEXR_COMPRESSIONTYPE_PIZ) {
+        SetErrorMessage("PIZ compression is not supported in this build",
+                        err);
+        return 0;
+      }
+#endif
+#if !TINYEXR_USE_ZFP
+      if (exr_headers[i]->compression_type == TINYEXR_COMPRESSIONTYPE_ZFP) {
+        SetErrorMessage("ZFP compression is not supported in this build",
+                        err);
+        return 0;
+      }
+#else
+      for (int c = 0; c < exr_header->num_channels; ++c) {
+        if (exr_headers[i]->requested_pixel_types[c] != TINYEXR_PIXELTYPE_FLOAT) {
+          SetErrorMessage("Pixel type must be FLOAT for ZFP compression",
+                          err);
+          return 0;
+        }
+      }
+#endif
+    }
+  }
+
+  std::vector<unsigned char> memory;
+
+  // Header
+  {
+    const char header[] = { 0x76, 0x2f, 0x31, 0x01 };
+    memory.insert(memory.end(), header, header + 4);
+  }
+
+  // Version
+  // using value from the first header
+  int long_name = exr_headers[0]->long_name;
+  {
+    char marker[] = { 2, 0, 0, 0 };
+    /* @todo
+    if (exr_header->non_image) {
+    marker[1] |= 0x8;
+    }
+    */
+    // tiled
+    if (num_parts == 1 && exr_images[0].tiles) {
+      marker[1] |= 0x2;
+    }
+    // long_name
+    if (long_name) {
+      marker[1] |= 0x4;
+    }
+    // multipart
+    if (num_parts > 1) {
+      marker[1] |= 0x10;
+    }
+    memory.insert(memory.end(), marker, marker + 4);
+  }
+
+  int total_chunk_count = 0;
+  std::vector<int> chunk_count(num_parts);
+  std::vector<OffsetData> offset_data(num_parts);
+  for (unsigned int i = 0; i < num_parts; ++i) {
+    if (!exr_images[i].tiles) {
+      int num_scanlines = NumScanlines(exr_headers[i]->compression_type);
+      chunk_count[i] =
+        (exr_images[i].height + num_scanlines - 1) / num_scanlines;
+      InitSingleResolutionOffsets(offset_data[i], chunk_count[i]);
+      total_chunk_count += chunk_count[i];
+    } else {
+      {
+        std::vector<int> num_x_tiles, num_y_tiles;
+        PrecalculateTileInfo(num_x_tiles, num_y_tiles, exr_headers[i]);
+        chunk_count[i] =
+          InitTileOffsets(offset_data[i], exr_headers[i], num_x_tiles, num_y_tiles);
+        total_chunk_count += chunk_count[i];
+      }
+    }
+  }
+  // Write attributes to memory buffer.
+  std::vector< std::vector<tinyexr::ChannelInfo> > channels(num_parts);
+  {
+    std::set<std::string> partnames;
+    for (unsigned int i = 0; i < num_parts; ++i) {
+      //channels
+      {
+        std::vector<unsigned char> data;
+
+        for (int c = 0; c < exr_headers[i]->num_channels; c++) {
+          tinyexr::ChannelInfo info;
+          info.p_linear = 0;
+          info.pixel_type = exr_headers[i]->pixel_types[c];
+          info.requested_pixel_type = exr_headers[i]->requested_pixel_types[c];
+          info.x_sampling = 1;
+          info.y_sampling = 1;
+          info.name = std::string(exr_headers[i]->channels[c].name);
+          channels[i].push_back(info);
+        }
+
+        tinyexr::WriteChannelInfo(data, channels[i]);
+
+        tinyexr::WriteAttributeToMemory(&memory, "channels", "chlist", &data.at(0),
+                                        static_cast<int>(data.size()));
+      }
+
+      {
+        int comp = exr_headers[i]->compression_type;
+        swap4(&comp);
+        WriteAttributeToMemory(
+          &memory, "compression", "compression",
+          reinterpret_cast<const unsigned char*>(&comp), 1);
+      }
+
+      {
+        int data[4] = { 0, 0, exr_images[i].width - 1, exr_images[i].height - 1 };
+        swap4(&data[0]);
+        swap4(&data[1]);
+        swap4(&data[2]);
+        swap4(&data[3]);
+        WriteAttributeToMemory(
+          &memory, "dataWindow", "box2i",
+          reinterpret_cast<const unsigned char*>(data), sizeof(int) * 4);
+
+        int data0[4] = { 0, 0, exr_images[0].width - 1, exr_images[0].height - 1 };
+        swap4(&data0[0]);
+        swap4(&data0[1]);
+        swap4(&data0[2]);
+        swap4(&data0[3]);
+        // Note: must be the same across parts (currently, using value from the first header)
+        WriteAttributeToMemory(
+          &memory, "displayWindow", "box2i",
+          reinterpret_cast<const unsigned char*>(data0), sizeof(int) * 4);
+      }
+
+      {
+        unsigned char line_order = 0;  // @fixme { read line_order from EXRHeader }
+        WriteAttributeToMemory(&memory, "lineOrder", "lineOrder",
+                               &line_order, 1);
+      }
+
+      {
+        // Note: must be the same across parts
+        float aspectRatio = 1.0f;
+        swap4(&aspectRatio);
+        WriteAttributeToMemory(
+          &memory, "pixelAspectRatio", "float",
+          reinterpret_cast<const unsigned char*>(&aspectRatio), sizeof(float));
+      }
+
+      {
+        float center[2] = { 0.0f, 0.0f };
+        swap4(&center[0]);
+        swap4(&center[1]);
+        WriteAttributeToMemory(
+          &memory, "screenWindowCenter", "v2f",
+          reinterpret_cast<const unsigned char*>(center), 2 * sizeof(float));
+      }
+
+      {
+        float w = 1.0f;
+        swap4(&w);
+        WriteAttributeToMemory(&memory, "screenWindowWidth", "float",
+                               reinterpret_cast<const unsigned char*>(&w),
+                               sizeof(float));
+      }
+
+      if (exr_images[i].tiles) {
+        unsigned char tile_mode = static_cast<unsigned char>(exr_headers[i]->tile_level_mode & 0x3);
+        if (exr_headers[i]->tile_rounding_mode) tile_mode |= (1u << 4u);
+        //unsigned char data[9] = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+        unsigned int datai[3] = { 0, 0, 0 };
+        unsigned char* data = reinterpret_cast<unsigned char*>(&datai[0]);
+        datai[0] = static_cast<unsigned int>(exr_headers[i]->tile_size_x);
+        datai[1] = static_cast<unsigned int>(exr_headers[i]->tile_size_y);
+        data[8] = tile_mode;
+        swap4(reinterpret_cast<unsigned int*>(&data[0]));
+        swap4(reinterpret_cast<unsigned int*>(&data[4]));
+        WriteAttributeToMemory(
+          &memory, "tiles", "tiledesc",
+          reinterpret_cast<const unsigned char*>(data), 9);
+      }
+
+      // must be present for multi-part files - according to spec.
+      if (num_parts > 1) {
+        // name
+        {
+          size_t len = 0;
+          if ((len = strlen(exr_headers[i]->name)) > 0) {
+            partnames.emplace(exr_headers[i]->name);
+            if (partnames.size() != i + 1) {
+              SetErrorMessage("'name' attributes must be unique for a multi-part file", err);
+              return 0;
+            }
+            WriteAttributeToMemory(
+              &memory, "name", "string",
+              reinterpret_cast<const unsigned char*>(exr_headers[i]->name),
+              static_cast<int>(len));
+          } else {
+            SetErrorMessage("Invalid 'name' attribute for a multi-part file", err);
+            return 0;
+          }
+        }
+        // type
+        {
+          const char* type = "scanlineimage";
+          if (exr_images[i].tiles) type = "tiledimage";
+          WriteAttributeToMemory(
+            &memory, "type", "string",
+            reinterpret_cast<const unsigned char*>(type),
+            static_cast<int>(strlen(type)));
+        }
+        // chunkCount
+        {
+          WriteAttributeToMemory(
+            &memory, "chunkCount", "int",
+            reinterpret_cast<const unsigned char*>(&chunk_count[i]),
+            4);
+        }
+      }
+
+      // Custom attributes
+      if (exr_headers[i]->num_custom_attributes > 0) {
+        for (int j = 0; j < exr_headers[i]->num_custom_attributes; j++) {
+          tinyexr::WriteAttributeToMemory(
+            &memory, exr_headers[i]->custom_attributes[j].name,
+            exr_headers[i]->custom_attributes[j].type,
+            reinterpret_cast<const unsigned char*>(
+              exr_headers[i]->custom_attributes[j].value),
+            exr_headers[i]->custom_attributes[j].size);
+        }
+      }
+
+      {  // end of header
+        memory.push_back(0);
+      }
+    }
+  }
+  if (num_parts > 1) {
+    // end of header list
+    memory.push_back(0);
+  }
+
+  tinyexr_uint64 chunk_offset = memory.size() + size_t(total_chunk_count) * sizeof(tinyexr_uint64);
+
+  tinyexr_uint64 total_size = 0;
+  std::vector< std::vector< std::vector<unsigned char> > > data_lists(num_parts);
+  for (unsigned int i = 0; i < num_parts; ++i) {
+    std::string e;
+    int ret = EncodeChunk(&exr_images[i], exr_headers[i],
+                          channels[i],
+                          chunk_count[i],
+                          // starting offset of current chunk after part-number
+                          chunk_offset,
+                          num_parts > 1,
+                          offset_data[i], // output: block offsets, must be initialized
+                          data_lists[i], // output
+                          total_size, // output
+                          &e);
+    if (ret != TINYEXR_SUCCESS) {
+      if (!e.empty()) {
+        tinyexr::SetErrorMessage(e, err);
+      }
+      return 0;
+    }
+    chunk_offset = total_size;
+  }
+
+  // Allocating required memory
+  if (total_size == 0) { // something went wrong
+    tinyexr::SetErrorMessage("Output memory size is zero", err);
+    return 0;
+  }
+  (*memory_out) = static_cast<unsigned char*>(malloc(total_size));
+
+  // Writing header
+  memcpy((*memory_out), &memory[0], memory.size());
+  unsigned char* memory_ptr = *memory_out + memory.size();
+  size_t sum = memory.size();
+
+  // Writing offset data for chunks
+  for (unsigned int i = 0; i < num_parts; ++i) {
+    if (exr_images[i].tiles) {
+      const EXRImage* level_image = &exr_images[i];
+      int num_levels = (exr_headers[i]->tile_level_mode != TINYEXR_TILE_RIPMAP_LEVELS) ?
+        offset_data[i].num_x_levels : (offset_data[i].num_x_levels * offset_data[i].num_y_levels);
+      for (int level_index = 0; level_index < num_levels; ++level_index) {
+        for (size_t j = 0; j < offset_data[i].offsets[level_index].size(); ++j) {
+          size_t num_bytes = sizeof(tinyexr_uint64) * offset_data[i].offsets[level_index][j].size();
+          sum += num_bytes;
+          assert(sum <= total_size);
+          memcpy(memory_ptr,
+                 reinterpret_cast<unsigned char*>(&offset_data[i].offsets[level_index][j][0]),
+                 num_bytes);
+          memory_ptr += num_bytes;
+        }
+        level_image = level_image->next_level;
+      }
+    } else {
+      size_t num_bytes = sizeof(tinyexr::tinyexr_uint64) * static_cast<size_t>(chunk_count[i]);
+      sum += num_bytes;
+      assert(sum <= total_size);
+      std::vector<tinyexr::tinyexr_uint64>& offsets = offset_data[i].offsets[0][0];
+      memcpy(memory_ptr, reinterpret_cast<unsigned char*>(&offsets[0]), num_bytes);
+      memory_ptr += num_bytes;
+    }
+  }
+
+  // Writing chunk data
+  for (unsigned int i = 0; i < num_parts; ++i) {
+    for (size_t j = 0; j < static_cast<size_t>(chunk_count[i]); ++j) {
+      if (num_parts > 1) {
+        sum += 4;
+        assert(sum <= total_size);
+        unsigned int part_number = i;
+        swap4(&part_number);
+        memcpy(memory_ptr, &part_number, 4);
+        memory_ptr += 4;
+      }
+      sum += data_lists[i][j].size();
+      assert(sum <= total_size);
+      memcpy(memory_ptr, &data_lists[i][j][0], data_lists[i][j].size());
+      memory_ptr += data_lists[i][j].size();
+    }
+  }
+  assert(sum == total_size);
+  return total_size;  // OK
+}
+
+} // tinyexr
+
+size_t SaveEXRImageToMemory(const EXRImage* exr_image,
+                             const EXRHeader* exr_header,
+                             unsigned char** memory_out, const char** err) {
+  return tinyexr::SaveEXRNPartImageToMemory(exr_image, &exr_header, 1, memory_out, err);
+}
+
+int SaveEXRImageToFile(const EXRImage *exr_image, const EXRHeader *exr_header,
+                       const char *filename, const char **err) {
+  if (exr_image == NULL || filename == NULL ||
+      exr_header->compression_type < 0) {
+    tinyexr::SetErrorMessage("Invalid argument for SaveEXRImageToFile", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+#if !TINYEXR_USE_PIZ
+  if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_PIZ) {
+    tinyexr::SetErrorMessage("PIZ compression is not supported in this build",
+                             err);
+    return TINYEXR_ERROR_UNSUPPORTED_FEATURE;
+  }
+#endif
+
+#if !TINYEXR_USE_ZFP
+  if (exr_header->compression_type == TINYEXR_COMPRESSIONTYPE_ZFP) {
+    tinyexr::SetErrorMessage("ZFP compression is not supported in this build",
+                             err);
+    return TINYEXR_ERROR_UNSUPPORTED_FEATURE;
+  }
+#endif
+
+  FILE *fp = NULL;
+#ifdef _WIN32
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang
+  errno_t errcode =
+      _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"wb");
+  if (errcode != 0) {
+    tinyexr::SetErrorMessage("Cannot write a file: " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_CANT_WRITE_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "wb");
+#endif
+#else
+  fp = fopen(filename, "wb");
+#endif
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot write a file: " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_CANT_WRITE_FILE;
+  }
+
+  unsigned char *mem = NULL;
+  size_t mem_size = SaveEXRImageToMemory(exr_image, exr_header, &mem, err);
+  if (mem_size == 0) {
+    return TINYEXR_ERROR_SERIALZATION_FAILED;
+  }
+
+  size_t written_size = 0;
+  if ((mem_size > 0) && mem) {
+    written_size = fwrite(mem, 1, mem_size, fp);
+  }
+  free(mem);
+
+  fclose(fp);
+
+  if (written_size != mem_size) {
+    tinyexr::SetErrorMessage("Cannot write a file", err);
+    return TINYEXR_ERROR_CANT_WRITE_FILE;
+  }
+
+  return TINYEXR_SUCCESS;
+}
+
+size_t SaveEXRMultipartImageToMemory(const EXRImage* exr_images,
+                                     const EXRHeader** exr_headers,
+                                     unsigned int num_parts,
+                                     unsigned char** memory_out, const char** err) {
+  if (exr_images == NULL || exr_headers == NULL || num_parts < 2 ||
+      memory_out == NULL) {
+    tinyexr::SetErrorMessage("Invalid argument for SaveEXRNPartImageToMemory",
+                              err);
+    return 0;
+  }
+  return tinyexr::SaveEXRNPartImageToMemory(exr_images, exr_headers, num_parts, memory_out, err);
+}
+
+int SaveEXRMultipartImageToFile(const EXRImage* exr_images,
+                                const EXRHeader** exr_headers,
+                                unsigned int num_parts,
+                                const char* filename,
+                                const char** err) {
+  if (exr_images == NULL || exr_headers == NULL || num_parts < 2) {
+    tinyexr::SetErrorMessage("Invalid argument for SaveEXRMultipartImageToFile",
+                              err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  FILE *fp = NULL;
+#ifdef _WIN32
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang.
+  errno_t errcode =
+    _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"wb");
+  if (errcode != 0) {
+    tinyexr::SetErrorMessage("Cannot write a file: " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_CANT_WRITE_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "wb");
+#endif
+#else
+  fp = fopen(filename, "wb");
+#endif
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot write a file: " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_CANT_WRITE_FILE;
+  }
+
+  unsigned char *mem = NULL;
+  size_t mem_size = SaveEXRMultipartImageToMemory(exr_images, exr_headers, num_parts, &mem, err);
+  if (mem_size == 0) {
+    return TINYEXR_ERROR_SERIALZATION_FAILED;
+  }
+
+  size_t written_size = 0;
+  if ((mem_size > 0) && mem) {
+    written_size = fwrite(mem, 1, mem_size, fp);
+  }
+  free(mem);
+
+  fclose(fp);
+
+  if (written_size != mem_size) {
+    tinyexr::SetErrorMessage("Cannot write a file", err);
+    return TINYEXR_ERROR_CANT_WRITE_FILE;
+  }
+
+  return TINYEXR_SUCCESS;
+}
+
+int LoadDeepEXR(DeepImage *deep_image, const char *filename, const char **err) {
+  if (deep_image == NULL) {
+    tinyexr::SetErrorMessage("Invalid argument for LoadDeepEXR", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+#ifdef _WIN32
+  FILE *fp = NULL;
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang.
+  errno_t errcode =
+      _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"rb");
+  if (errcode != 0) {
+    tinyexr::SetErrorMessage("Cannot read a file " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "rb");
+#endif
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot read a file " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+#else
+  FILE *fp = fopen(filename, "rb");
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot read a file " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+#endif
+
+  size_t filesize;
+  // Compute size
+  fseek(fp, 0, SEEK_END);
+  filesize = static_cast<size_t>(ftell(fp));
+  fseek(fp, 0, SEEK_SET);
+
+  if (filesize == 0) {
+    fclose(fp);
+    tinyexr::SetErrorMessage("File size is zero : " + std::string(filename),
+                             err);
+    return TINYEXR_ERROR_INVALID_FILE;
+  }
+
+  std::vector<char> buf(filesize);  // @todo { use mmap }
+  {
+    size_t ret;
+    ret = fread(&buf[0], 1, filesize, fp);
+    assert(ret == filesize);
+    (void)ret;
+  }
+  fclose(fp);
+
+  const char *head = &buf[0];
+  const char *marker = &buf[0];
+
+  // Header check.
+  {
+    const char header[] = {0x76, 0x2f, 0x31, 0x01};
+
+    if (memcmp(marker, header, 4) != 0) {
+      tinyexr::SetErrorMessage("Invalid magic number", err);
+      return TINYEXR_ERROR_INVALID_MAGIC_NUMBER;
+    }
+    marker += 4;
+  }
+
+  // Version, scanline.
+  {
+    // ver 2.0, scanline, deep bit on(0x800)
+    // must be [2, 0, 0, 0]
+    if (marker[0] != 2 || marker[1] != 8 || marker[2] != 0 || marker[3] != 0) {
+      tinyexr::SetErrorMessage("Unsupported version or scanline", err);
+      return TINYEXR_ERROR_UNSUPPORTED_FORMAT;
+    }
+
+    marker += 4;
+  }
+
+  int dx = -1;
+  int dy = -1;
+  int dw = -1;
+  int dh = -1;
+  int num_scanline_blocks = 1;  // 16 for ZIP compression.
+  int compression_type = -1;
+  int num_channels = -1;
+  std::vector<tinyexr::ChannelInfo> channels;
+
+  // Read attributes
+  size_t size = filesize - tinyexr::kEXRVersionSize;
+  for (;;) {
+    if (0 == size) {
+      return TINYEXR_ERROR_INVALID_DATA;
+    } else if (marker[0] == '\0') {
+      marker++;
+      size--;
+      break;
+    }
+
+    std::string attr_name;
+    std::string attr_type;
+    std::vector<unsigned char> data;
+    size_t marker_size;
+    if (!tinyexr::ReadAttribute(&attr_name, &attr_type, &data, &marker_size,
+                                marker, size)) {
+      std::stringstream ss;
+      ss << "Failed to parse attribute\n";
+      tinyexr::SetErrorMessage(ss.str(), err);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+    marker += marker_size;
+    size -= marker_size;
+
+    if (attr_name.compare("compression") == 0) {
+      compression_type = data[0];
+      if (compression_type > TINYEXR_COMPRESSIONTYPE_PIZ) {
+        std::stringstream ss;
+        ss << "Unsupported compression type : " << compression_type;
+        tinyexr::SetErrorMessage(ss.str(), err);
+        return TINYEXR_ERROR_UNSUPPORTED_FORMAT;
+      }
+
+      if (compression_type == TINYEXR_COMPRESSIONTYPE_ZIP) {
+        num_scanline_blocks = 16;
+      }
+
+    } else if (attr_name.compare("channels") == 0) {
+      // name: zero-terminated string, from 1 to 255 bytes long
+      // pixel type: int, possible values are: UINT = 0 HALF = 1 FLOAT = 2
+      // pLinear: unsigned char, possible values are 0 and 1
+      // reserved: three chars, should be zero
+      // xSampling: int
+      // ySampling: int
+
+      if (!tinyexr::ReadChannelInfo(channels, data)) {
+        tinyexr::SetErrorMessage("Failed to parse channel info", err);
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+
+      num_channels = static_cast<int>(channels.size());
+
+      if (num_channels < 1) {
+        tinyexr::SetErrorMessage("Invalid channels format", err);
+        return TINYEXR_ERROR_INVALID_DATA;
+      }
+
+    } else if (attr_name.compare("dataWindow") == 0) {
+      memcpy(&dx, &data.at(0), sizeof(int));
+      memcpy(&dy, &data.at(4), sizeof(int));
+      memcpy(&dw, &data.at(8), sizeof(int));
+      memcpy(&dh, &data.at(12), sizeof(int));
+      tinyexr::swap4(&dx);
+      tinyexr::swap4(&dy);
+      tinyexr::swap4(&dw);
+      tinyexr::swap4(&dh);
+
+    } else if (attr_name.compare("displayWindow") == 0) {
+      int x;
+      int y;
+      int w;
+      int h;
+      memcpy(&x, &data.at(0), sizeof(int));
+      memcpy(&y, &data.at(4), sizeof(int));
+      memcpy(&w, &data.at(8), sizeof(int));
+      memcpy(&h, &data.at(12), sizeof(int));
+      tinyexr::swap4(&x);
+      tinyexr::swap4(&y);
+      tinyexr::swap4(&w);
+      tinyexr::swap4(&h);
+    }
+  }
+
+  assert(dx >= 0);
+  assert(dy >= 0);
+  assert(dw >= 0);
+  assert(dh >= 0);
+  assert(num_channels >= 1);
+
+  int data_width = dw - dx + 1;
+  int data_height = dh - dy + 1;
+
+  // Read offset tables.
+  int num_blocks = data_height / num_scanline_blocks;
+  if (num_blocks * num_scanline_blocks < data_height) {
+    num_blocks++;
+  }
+
+  std::vector<tinyexr::tinyexr_int64> offsets(static_cast<size_t>(num_blocks));
+
+  for (size_t y = 0; y < static_cast<size_t>(num_blocks); y++) {
+    tinyexr::tinyexr_int64 offset;
+    memcpy(&offset, marker, sizeof(tinyexr::tinyexr_int64));
+    tinyexr::swap8(reinterpret_cast<tinyexr::tinyexr_uint64 *>(&offset));
+    marker += sizeof(tinyexr::tinyexr_int64);  // = 8
+    offsets[y] = offset;
+  }
+
+#if TINYEXR_USE_PIZ
+  if ((compression_type == TINYEXR_COMPRESSIONTYPE_NONE) ||
+      (compression_type == TINYEXR_COMPRESSIONTYPE_RLE) ||
+      (compression_type == TINYEXR_COMPRESSIONTYPE_ZIPS) ||
+      (compression_type == TINYEXR_COMPRESSIONTYPE_ZIP) ||
+      (compression_type == TINYEXR_COMPRESSIONTYPE_PIZ)) {
+#else
+  if ((compression_type == TINYEXR_COMPRESSIONTYPE_NONE) ||
+      (compression_type == TINYEXR_COMPRESSIONTYPE_RLE) ||
+      (compression_type == TINYEXR_COMPRESSIONTYPE_ZIPS) ||
+      (compression_type == TINYEXR_COMPRESSIONTYPE_ZIP)) {
+#endif
+    // OK
+  } else {
+    tinyexr::SetErrorMessage("Unsupported compression format", err);
+    return TINYEXR_ERROR_UNSUPPORTED_FORMAT;
+  }
+
+  deep_image->image = static_cast<float ***>(
+      malloc(sizeof(float **) * static_cast<size_t>(num_channels)));
+  for (int c = 0; c < num_channels; c++) {
+    deep_image->image[c] = static_cast<float **>(
+        malloc(sizeof(float *) * static_cast<size_t>(data_height)));
+    for (int y = 0; y < data_height; y++) {
+    }
+  }
+
+  deep_image->offset_table = static_cast<int **>(
+      malloc(sizeof(int *) * static_cast<size_t>(data_height)));
+  for (int y = 0; y < data_height; y++) {
+    deep_image->offset_table[y] = static_cast<int *>(
+        malloc(sizeof(int) * static_cast<size_t>(data_width)));
+  }
+
+  for (size_t y = 0; y < static_cast<size_t>(num_blocks); y++) {
+    const unsigned char *data_ptr =
+        reinterpret_cast<const unsigned char *>(head + offsets[y]);
+
+    // int: y coordinate
+    // int64: packed size of pixel offset table
+    // int64: packed size of sample data
+    // int64: unpacked size of sample data
+    // compressed pixel offset table
+    // compressed sample data
+    int line_no;
+    tinyexr::tinyexr_int64 packedOffsetTableSize;
+    tinyexr::tinyexr_int64 packedSampleDataSize;
+    tinyexr::tinyexr_int64 unpackedSampleDataSize;
+    memcpy(&line_no, data_ptr, sizeof(int));
+    memcpy(&packedOffsetTableSize, data_ptr + 4,
+           sizeof(tinyexr::tinyexr_int64));
+    memcpy(&packedSampleDataSize, data_ptr + 12,
+           sizeof(tinyexr::tinyexr_int64));
+    memcpy(&unpackedSampleDataSize, data_ptr + 20,
+           sizeof(tinyexr::tinyexr_int64));
+
+    tinyexr::swap4(&line_no);
+    tinyexr::swap8(
+        reinterpret_cast<tinyexr::tinyexr_uint64 *>(&packedOffsetTableSize));
+    tinyexr::swap8(
+        reinterpret_cast<tinyexr::tinyexr_uint64 *>(&packedSampleDataSize));
+    tinyexr::swap8(
+        reinterpret_cast<tinyexr::tinyexr_uint64 *>(&unpackedSampleDataSize));
+
+    std::vector<int> pixelOffsetTable(static_cast<size_t>(data_width));
+
+    // decode pixel offset table.
+    {
+      unsigned long dstLen =
+          static_cast<unsigned long>(pixelOffsetTable.size() * sizeof(int));
+      if (!tinyexr::DecompressZip(
+              reinterpret_cast<unsigned char *>(&pixelOffsetTable.at(0)),
+              &dstLen, data_ptr + 28,
+              static_cast<unsigned long>(packedOffsetTableSize))) {
+        return false;
+      }
+
+      assert(dstLen == pixelOffsetTable.size() * sizeof(int));
+      for (size_t i = 0; i < static_cast<size_t>(data_width); i++) {
+        deep_image->offset_table[y][i] = pixelOffsetTable[i];
+      }
+    }
+
+    std::vector<unsigned char> sample_data(
+        static_cast<size_t>(unpackedSampleDataSize));
+
+    // decode sample data.
+    {
+      unsigned long dstLen = static_cast<unsigned long>(unpackedSampleDataSize);
+      if (dstLen) {
+        if (!tinyexr::DecompressZip(
+                reinterpret_cast<unsigned char *>(&sample_data.at(0)), &dstLen,
+                data_ptr + 28 + packedOffsetTableSize,
+                static_cast<unsigned long>(packedSampleDataSize))) {
+          return false;
+        }
+        assert(dstLen == static_cast<unsigned long>(unpackedSampleDataSize));
+      }
+    }
+
+    // decode sample
+    int sampleSize = -1;
+    std::vector<int> channel_offset_list(static_cast<size_t>(num_channels));
+    {
+      int channel_offset = 0;
+      for (size_t i = 0; i < static_cast<size_t>(num_channels); i++) {
+        channel_offset_list[i] = channel_offset;
+        if (channels[i].pixel_type == TINYEXR_PIXELTYPE_UINT) {  // UINT
+          channel_offset += 4;
+        } else if (channels[i].pixel_type == TINYEXR_PIXELTYPE_HALF) {  // half
+          channel_offset += 2;
+        } else if (channels[i].pixel_type ==
+                   TINYEXR_PIXELTYPE_FLOAT) {  // float
+          channel_offset += 4;
+        } else {
+          assert(0);
+        }
+      }
+      sampleSize = channel_offset;
+    }
+    assert(sampleSize >= 2);
+
+    assert(static_cast<size_t>(
+               pixelOffsetTable[static_cast<size_t>(data_width - 1)] *
+               sampleSize) == sample_data.size());
+    int samples_per_line = static_cast<int>(sample_data.size()) / sampleSize;
+
+    //
+    // Alloc memory
+    //
+
+    //
+    // pixel data is stored as image[channels][pixel_samples]
+    //
+    {
+      tinyexr::tinyexr_uint64 data_offset = 0;
+      for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+        deep_image->image[c][y] = static_cast<float *>(
+            malloc(sizeof(float) * static_cast<size_t>(samples_per_line)));
+
+        if (channels[c].pixel_type == 0) {  // UINT
+          for (size_t x = 0; x < static_cast<size_t>(samples_per_line); x++) {
+            unsigned int ui;
+            unsigned int *src_ptr = reinterpret_cast<unsigned int *>(
+                &sample_data.at(size_t(data_offset) + x * sizeof(int)));
+            tinyexr::cpy4(&ui, src_ptr);
+            deep_image->image[c][y][x] = static_cast<float>(ui);  // @fixme
+          }
+          data_offset +=
+              sizeof(unsigned int) * static_cast<size_t>(samples_per_line);
+        } else if (channels[c].pixel_type == 1) {  // half
+          for (size_t x = 0; x < static_cast<size_t>(samples_per_line); x++) {
+            tinyexr::FP16 f16;
+            const unsigned short *src_ptr = reinterpret_cast<unsigned short *>(
+                &sample_data.at(size_t(data_offset) + x * sizeof(short)));
+            tinyexr::cpy2(&(f16.u), src_ptr);
+            tinyexr::FP32 f32 = half_to_float(f16);
+            deep_image->image[c][y][x] = f32.f;
+          }
+          data_offset += sizeof(short) * static_cast<size_t>(samples_per_line);
+        } else {  // float
+          for (size_t x = 0; x < static_cast<size_t>(samples_per_line); x++) {
+            float f;
+            const float *src_ptr = reinterpret_cast<float *>(
+                &sample_data.at(size_t(data_offset) + x * sizeof(float)));
+            tinyexr::cpy4(&f, src_ptr);
+            deep_image->image[c][y][x] = f;
+          }
+          data_offset += sizeof(float) * static_cast<size_t>(samples_per_line);
+        }
+      }
+    }
+  }  // y
+
+  deep_image->width = data_width;
+  deep_image->height = data_height;
+
+  deep_image->channel_names = static_cast<const char **>(
+      malloc(sizeof(const char *) * static_cast<size_t>(num_channels)));
+  for (size_t c = 0; c < static_cast<size_t>(num_channels); c++) {
+#ifdef _WIN32
+    deep_image->channel_names[c] = _strdup(channels[c].name.c_str());
+#else
+    deep_image->channel_names[c] = strdup(channels[c].name.c_str());
+#endif
+  }
+  deep_image->num_channels = num_channels;
+
+  return TINYEXR_SUCCESS;
+}
+
+void InitEXRImage(EXRImage *exr_image) {
+  if (exr_image == NULL) {
+    return;
+  }
+
+  exr_image->width = 0;
+  exr_image->height = 0;
+  exr_image->num_channels = 0;
+
+  exr_image->images = NULL;
+  exr_image->tiles = NULL;
+  exr_image->next_level = NULL;
+  exr_image->level_x = 0;
+  exr_image->level_y = 0;
+
+  exr_image->num_tiles = 0;
+}
+
+void FreeEXRErrorMessage(const char *msg) {
+  if (msg) {
+    free(reinterpret_cast<void *>(const_cast<char *>(msg)));
+  }
+  return;
+}
+
+void InitEXRHeader(EXRHeader *exr_header) {
+  if (exr_header == NULL) {
+    return;
+  }
+
+  memset(exr_header, 0, sizeof(EXRHeader));
+}
+
+int FreeEXRHeader(EXRHeader *exr_header) {
+  if (exr_header == NULL) {
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  if (exr_header->channels) {
+    free(exr_header->channels);
+  }
+
+  if (exr_header->pixel_types) {
+    free(exr_header->pixel_types);
+  }
+
+  if (exr_header->requested_pixel_types) {
+    free(exr_header->requested_pixel_types);
+  }
+
+  for (int i = 0; i < exr_header->num_custom_attributes; i++) {
+    if (exr_header->custom_attributes[i].value) {
+      free(exr_header->custom_attributes[i].value);
+    }
+  }
+
+  if (exr_header->custom_attributes) {
+    free(exr_header->custom_attributes);
+  }
+
+  EXRSetNameAttr(exr_header, NULL);
+
+  return TINYEXR_SUCCESS;
+}
+
+void EXRSetNameAttr(EXRHeader* exr_header, const char* name) {
+  if (exr_header == NULL) {
+    return;
+  }
+  memset(exr_header->name, 0, 256);
+  if (name != NULL) {
+    size_t len = std::min(strlen(name), (size_t)255);
+    if (len) {
+      memcpy(exr_header->name, name, len);
+    }
+  }
+}
+
+int EXRNumLevels(const EXRImage* exr_image) {
+  if (exr_image == NULL) return 0;
+  if(exr_image->images) return 1; // scanlines
+  int levels = 1;
+  const EXRImage* level_image = exr_image;
+  while((level_image = level_image->next_level)) ++levels;
+  return levels;
+}
+
+int FreeEXRImage(EXRImage *exr_image) {
+  if (exr_image == NULL) {
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  if (exr_image->next_level) {
+    FreeEXRImage(exr_image->next_level);
+    delete exr_image->next_level;
+  }
+
+  for (int i = 0; i < exr_image->num_channels; i++) {
+    if (exr_image->images && exr_image->images[i]) {
+      free(exr_image->images[i]);
+    }
+  }
+
+  if (exr_image->images) {
+    free(exr_image->images);
+  }
+
+  if (exr_image->tiles) {
+    for (int tid = 0; tid < exr_image->num_tiles; tid++) {
+      for (int i = 0; i < exr_image->num_channels; i++) {
+        if (exr_image->tiles[tid].images && exr_image->tiles[tid].images[i]) {
+          free(exr_image->tiles[tid].images[i]);
+        }
+      }
+      if (exr_image->tiles[tid].images) {
+        free(exr_image->tiles[tid].images);
+      }
+    }
+    free(exr_image->tiles);
+  }
+
+  return TINYEXR_SUCCESS;
+}
+
+int ParseEXRHeaderFromFile(EXRHeader *exr_header, const EXRVersion *exr_version,
+                           const char *filename, const char **err) {
+  if (exr_header == NULL || exr_version == NULL || filename == NULL) {
+    tinyexr::SetErrorMessage("Invalid argument for ParseEXRHeaderFromFile",
+                             err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  FILE *fp = NULL;
+#ifdef _WIN32
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang.
+  errno_t errcode =
+      _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"rb");
+  if (errcode != 0) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    return TINYEXR_ERROR_INVALID_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "rb");
+#endif
+#else
+  fp = fopen(filename, "rb");
+#endif
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+
+  size_t filesize;
+  // Compute size
+  fseek(fp, 0, SEEK_END);
+  filesize = static_cast<size_t>(ftell(fp));
+  fseek(fp, 0, SEEK_SET);
+
+  std::vector<unsigned char> buf(filesize);  // @todo { use mmap }
+  {
+    size_t ret;
+    ret = fread(&buf[0], 1, filesize, fp);
+    assert(ret == filesize);
+    fclose(fp);
+
+    if (ret != filesize) {
+      tinyexr::SetErrorMessage("fread() error on " + std::string(filename),
+                               err);
+      return TINYEXR_ERROR_INVALID_FILE;
+    }
+  }
+
+  return ParseEXRHeaderFromMemory(exr_header, exr_version, &buf.at(0), filesize,
+                                  err);
+}
+
+int ParseEXRMultipartHeaderFromMemory(EXRHeader ***exr_headers,
+                                      int *num_headers,
+                                      const EXRVersion *exr_version,
+                                      const unsigned char *memory, size_t size,
+                                      const char **err) {
+  if (memory == NULL || exr_headers == NULL || num_headers == NULL ||
+      exr_version == NULL) {
+    // Invalid argument
+    tinyexr::SetErrorMessage(
+        "Invalid argument for ParseEXRMultipartHeaderFromMemory", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  if (size < tinyexr::kEXRVersionSize) {
+    tinyexr::SetErrorMessage("Data size too short", err);
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+
+  const unsigned char *marker = memory + tinyexr::kEXRVersionSize;
+  size_t marker_size = size - tinyexr::kEXRVersionSize;
+
+  std::vector<tinyexr::HeaderInfo> infos;
+
+  for (;;) {
+    tinyexr::HeaderInfo info;
+    info.clear();
+
+    std::string err_str;
+    bool empty_header = false;
+    int ret = ParseEXRHeader(&info, &empty_header, exr_version, &err_str,
+                             marker, marker_size);
+
+    if (ret != TINYEXR_SUCCESS) {
+      tinyexr::SetErrorMessage(err_str, err);
+      return ret;
+    }
+
+    if (empty_header) {
+      marker += 1;  // skip '\0'
+      break;
+    }
+
+    // `chunkCount` must exist in the header.
+    if (info.chunk_count == 0) {
+      tinyexr::SetErrorMessage(
+          "`chunkCount' attribute is not found in the header.", err);
+      return TINYEXR_ERROR_INVALID_DATA;
+    }
+
+    infos.push_back(info);
+
+    // move to next header.
+    marker += info.header_len;
+    size -= info.header_len;
+  }
+
+  // allocate memory for EXRHeader and create array of EXRHeader pointers.
+  (*exr_headers) =
+      static_cast<EXRHeader **>(malloc(sizeof(EXRHeader *) * infos.size()));
+
+  
+  int retcode = TINYEXR_SUCCESS;
+
+  for (size_t i = 0; i < infos.size(); i++) {
+    EXRHeader *exr_header = static_cast<EXRHeader *>(malloc(sizeof(EXRHeader)));
+    memset(exr_header, 0, sizeof(EXRHeader));
+
+    std::string warn;
+    std::string _err;
+    if (!ConvertHeader(exr_header, infos[i], &warn, &_err)) {
+      if (!_err.empty()) {
+        tinyexr::SetErrorMessage(
+            _err, err);
+      }
+      // continue to converting headers
+      retcode = TINYEXR_ERROR_INVALID_HEADER;
+    }
+
+    exr_header->multipart = exr_version->multipart ? 1 : 0;
+
+    (*exr_headers)[i] = exr_header;
+  }
+
+  (*num_headers) = static_cast<int>(infos.size());
+
+  return retcode;
+}
+
+int ParseEXRMultipartHeaderFromFile(EXRHeader ***exr_headers, int *num_headers,
+                                    const EXRVersion *exr_version,
+                                    const char *filename, const char **err) {
+  if (exr_headers == NULL || num_headers == NULL || exr_version == NULL ||
+      filename == NULL) {
+    tinyexr::SetErrorMessage(
+        "Invalid argument for ParseEXRMultipartHeaderFromFile()", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  FILE *fp = NULL;
+#ifdef _WIN32
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang.
+  errno_t errcode =
+      _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"rb");
+  if (errcode != 0) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    return TINYEXR_ERROR_INVALID_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "rb");
+#endif
+#else
+  fp = fopen(filename, "rb");
+#endif
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+
+  size_t filesize;
+  // Compute size
+  fseek(fp, 0, SEEK_END);
+  filesize = static_cast<size_t>(ftell(fp));
+  fseek(fp, 0, SEEK_SET);
+
+  std::vector<unsigned char> buf(filesize);  // @todo { use mmap }
+  {
+    size_t ret;
+    ret = fread(&buf[0], 1, filesize, fp);
+    assert(ret == filesize);
+    fclose(fp);
+
+    if (ret != filesize) {
+      tinyexr::SetErrorMessage("`fread' error. file may be corrupted.", err);
+      return TINYEXR_ERROR_INVALID_FILE;
+    }
+  }
+
+  return ParseEXRMultipartHeaderFromMemory(
+      exr_headers, num_headers, exr_version, &buf.at(0), filesize, err);
+}
+
+int ParseEXRVersionFromMemory(EXRVersion *version, const unsigned char *memory,
+                              size_t size) {
+  if (version == NULL || memory == NULL) {
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  if (size < tinyexr::kEXRVersionSize) {
+    return TINYEXR_ERROR_INVALID_DATA;
+  }
+
+  const unsigned char *marker = memory;
+
+  // Header check.
+  {
+    const char header[] = {0x76, 0x2f, 0x31, 0x01};
+
+    if (memcmp(marker, header, 4) != 0) {
+      return TINYEXR_ERROR_INVALID_MAGIC_NUMBER;
+    }
+    marker += 4;
+  }
+
+  version->tiled = false;
+  version->long_name = false;
+  version->non_image = false;
+  version->multipart = false;
+
+  // Parse version header.
+  {
+    // must be 2
+    if (marker[0] != 2) {
+      return TINYEXR_ERROR_INVALID_EXR_VERSION;
+    }
+
+    if (version == NULL) {
+      return TINYEXR_SUCCESS;  // May OK
+    }
+
+    version->version = 2;
+
+    if (marker[1] & 0x2) {  // 9th bit
+      version->tiled = true;
+    }
+    if (marker[1] & 0x4) {  // 10th bit
+      version->long_name = true;
+    }
+    if (marker[1] & 0x8) {        // 11th bit
+      version->non_image = true;  // (deep image)
+    }
+    if (marker[1] & 0x10) {  // 12th bit
+      version->multipart = true;
+    }
+  }
+
+  return TINYEXR_SUCCESS;
+}
+
+int ParseEXRVersionFromFile(EXRVersion *version, const char *filename) {
+  if (filename == NULL) {
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  FILE *fp = NULL;
+#ifdef _WIN32
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang.
+  errno_t err = _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"rb");
+  if (err != 0) {
+    // TODO(syoyo): return wfopen_s erro code
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "rb");
+#endif
+#else
+  fp = fopen(filename, "rb");
+#endif
+  if (!fp) {
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+
+  size_t file_size;
+  // Compute size
+  fseek(fp, 0, SEEK_END);
+  file_size = static_cast<size_t>(ftell(fp));
+  fseek(fp, 0, SEEK_SET);
+
+  if (file_size < tinyexr::kEXRVersionSize) {
+    return TINYEXR_ERROR_INVALID_FILE;
+  }
+
+  unsigned char buf[tinyexr::kEXRVersionSize];
+  size_t ret = fread(&buf[0], 1, tinyexr::kEXRVersionSize, fp);
+  fclose(fp);
+
+  if (ret != tinyexr::kEXRVersionSize) {
+    return TINYEXR_ERROR_INVALID_FILE;
+  }
+
+  return ParseEXRVersionFromMemory(version, buf, tinyexr::kEXRVersionSize);
+}
+
+int LoadEXRMultipartImageFromMemory(EXRImage *exr_images,
+                                    const EXRHeader **exr_headers,
+                                    unsigned int num_parts,
+                                    const unsigned char *memory,
+                                    const size_t size, const char **err) {
+  if (exr_images == NULL || exr_headers == NULL || num_parts == 0 ||
+      memory == NULL || (size <= tinyexr::kEXRVersionSize)) {
+    tinyexr::SetErrorMessage(
+        "Invalid argument for LoadEXRMultipartImageFromMemory()", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  // compute total header size.
+  size_t total_header_size = 0;
+  for (unsigned int i = 0; i < num_parts; i++) {
+    if (exr_headers[i]->header_len == 0) {
+      tinyexr::SetErrorMessage("EXRHeader variable is not initialized.", err);
+      return TINYEXR_ERROR_INVALID_ARGUMENT;
+    }
+
+    total_header_size += exr_headers[i]->header_len;
+  }
+
+  const char *marker = reinterpret_cast<const char *>(
+      memory + total_header_size + 4 +
+      4);  // +8 for magic number and version header.
+
+  marker += 1;  // Skip empty header.
+
+  // NOTE 1:
+  //   In multipart image, There is 'part number' before chunk data.
+  //   4 byte : part number
+  //   4+     : chunk
+  //
+  // NOTE 2:
+  //   EXR spec says 'part number' is 'unsigned long' but actually this is
+  //   'unsigned int(4 bytes)' in OpenEXR implementation...
+  //   http://www.openexr.com/openexrfilelayout.pdf
+
+  // Load chunk offset table.
+  std::vector<tinyexr::OffsetData> chunk_offset_table_list;
+  chunk_offset_table_list.reserve(num_parts);
+  for (size_t i = 0; i < static_cast<size_t>(num_parts); i++) {
+    chunk_offset_table_list.resize(chunk_offset_table_list.size() + 1);
+    tinyexr::OffsetData& offset_data = chunk_offset_table_list.back();
+    if (!exr_headers[i]->tiled || exr_headers[i]->tile_level_mode == TINYEXR_TILE_ONE_LEVEL) {
+      tinyexr::InitSingleResolutionOffsets(offset_data, exr_headers[i]->chunk_count);
+      std::vector<tinyexr::tinyexr_uint64>& offset_table = offset_data.offsets[0][0];
+
+      for (size_t c = 0; c < offset_table.size(); c++) {
+        tinyexr::tinyexr_uint64 offset;
+        memcpy(&offset, marker, 8);
+        tinyexr::swap8(&offset);
+
+        if (offset >= size) {
+          tinyexr::SetErrorMessage("Invalid offset size in EXR header chunks.",
+                                   err);
+          return TINYEXR_ERROR_INVALID_DATA;
+        }
+
+        offset_table[c] = offset + 4;  // +4 to skip 'part number'
+        marker += 8;
+      }
+    } else {
+      {
+        std::vector<int> num_x_tiles, num_y_tiles;
+        tinyexr::PrecalculateTileInfo(num_x_tiles, num_y_tiles, exr_headers[i]);
+        int num_blocks = InitTileOffsets(offset_data, exr_headers[i], num_x_tiles, num_y_tiles);
+        if (num_blocks != exr_headers[i]->chunk_count) {
+          tinyexr::SetErrorMessage("Invalid offset table size.", err);
+          return TINYEXR_ERROR_INVALID_DATA;
+        }
+      }
+      for (unsigned int l = 0; l < offset_data.offsets.size(); ++l) {
+        for (unsigned int dy = 0; dy < offset_data.offsets[l].size(); ++dy) {
+          for (unsigned int dx = 0; dx < offset_data.offsets[l][dy].size(); ++dx) {
+            tinyexr::tinyexr_uint64 offset;
+            memcpy(&offset, marker, sizeof(tinyexr::tinyexr_uint64));
+            tinyexr::swap8(&offset);
+            if (offset >= size) {
+              tinyexr::SetErrorMessage("Invalid offset size in EXR header chunks.",
+                err);
+              return TINYEXR_ERROR_INVALID_DATA;
+            }
+            offset_data.offsets[l][dy][dx] = offset + 4; // +4 to skip 'part number'
+            marker += sizeof(tinyexr::tinyexr_uint64);  // = 8 
+          }
+        }
+      }
+    }
+  }
+
+  // Decode image.
+  for (size_t i = 0; i < static_cast<size_t>(num_parts); i++) {
+    tinyexr::OffsetData &offset_data = chunk_offset_table_list[i];
+
+    // First check 'part number' is identitical to 'i'
+    for (unsigned int l = 0; l < offset_data.offsets.size(); ++l)
+      for (unsigned int dy = 0; dy < offset_data.offsets[l].size(); ++dy)
+        for (unsigned int dx = 0; dx < offset_data.offsets[l][dy].size(); ++dx) {
+
+          const unsigned char *part_number_addr =
+              memory + offset_data.offsets[l][dy][dx] - 4;  // -4 to move to 'part number' field.
+          unsigned int part_no;
+          memcpy(&part_no, part_number_addr, sizeof(unsigned int));  // 4
+          tinyexr::swap4(&part_no);
+
+          if (part_no != i) {
+            tinyexr::SetErrorMessage("Invalid `part number' in EXR header chunks.",
+                                     err);
+            return TINYEXR_ERROR_INVALID_DATA;
+          }
+        }
+
+    std::string e;
+    int ret = tinyexr::DecodeChunk(&exr_images[i], exr_headers[i], offset_data,
+                                   memory, size, &e);
+    if (ret != TINYEXR_SUCCESS) {
+      if (!e.empty()) {
+        tinyexr::SetErrorMessage(e, err);
+      }
+      return ret;
+    }
+  }
+
+  return TINYEXR_SUCCESS;
+}
+
+int LoadEXRMultipartImageFromFile(EXRImage *exr_images,
+                                  const EXRHeader **exr_headers,
+                                  unsigned int num_parts, const char *filename,
+                                  const char **err) {
+  if (exr_images == NULL || exr_headers == NULL || num_parts == 0) {
+    tinyexr::SetErrorMessage(
+        "Invalid argument for LoadEXRMultipartImageFromFile", err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  FILE *fp = NULL;
+#ifdef _WIN32
+#if defined(_MSC_VER) || (defined(MINGW_HAS_SECURE_API) && MINGW_HAS_SECURE_API) // MSVC, MinGW GCC, or Clang.
+  errno_t errcode =
+      _wfopen_s(&fp, tinyexr::UTF8ToWchar(filename).c_str(), L"rb");
+  if (errcode != 0) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+#else
+  // Unknown compiler or MinGW without MINGW_HAS_SECURE_API.
+  fp = fopen(filename, "rb");
+#endif
+#else
+  fp = fopen(filename, "rb");
+#endif
+  if (!fp) {
+    tinyexr::SetErrorMessage("Cannot read file " + std::string(filename), err);
+    return TINYEXR_ERROR_CANT_OPEN_FILE;
+  }
+
+  size_t filesize;
+  // Compute size
+  fseek(fp, 0, SEEK_END);
+  filesize = static_cast<size_t>(ftell(fp));
+  fseek(fp, 0, SEEK_SET);
+
+  std::vector<unsigned char> buf(filesize);  //  @todo { use mmap }
+  {
+    size_t ret;
+    ret = fread(&buf[0], 1, filesize, fp);
+    assert(ret == filesize);
+    fclose(fp);
+    (void)ret;
+  }
+
+  return LoadEXRMultipartImageFromMemory(exr_images, exr_headers, num_parts,
+                                         &buf.at(0), filesize, err);
+}
+
+int SaveEXR(const float *data, int width, int height, int components,
+            const int save_as_fp16, const char *outfilename, const char **err) {
+  if ((components == 1) || components == 3 || components == 4) {
+    // OK
+  } else {
+    std::stringstream ss;
+    ss << "Unsupported component value : " << components << std::endl;
+
+    tinyexr::SetErrorMessage(ss.str(), err);
+    return TINYEXR_ERROR_INVALID_ARGUMENT;
+  }
+
+  EXRHeader header;
+  InitEXRHeader(&header);
+
+  if ((width < 16) && (height < 16)) {
+    // No compression for small image.
+    header.compression_type = TINYEXR_COMPRESSIONTYPE_NONE;
+  } else {
+    header.compression_type = TINYEXR_COMPRESSIONTYPE_ZIP;
+  }
+
+  EXRImage image;
+  InitEXRImage(&image);
+
+  image.num_channels = components;
+
+  std::vector<float> images[4];
+
+  if (components == 1) {
+    images[0].resize(static_cast<size_t>(width * height));
+    memcpy(images[0].data(), data, sizeof(float) * size_t(width * height));
+  } else {
+    images[0].resize(static_cast<size_t>(width * height));
+    images[1].resize(static_cast<size_t>(width * height));
+    images[2].resize(static_cast<size_t>(width * height));
+    images[3].resize(static_cast<size_t>(width * height));
+
+    // Split RGB(A)RGB(A)RGB(A)... into R, G and B(and A) layers
+    for (size_t i = 0; i < static_cast<size_t>(width * height); i++) {
+      images[0][i] = data[static_cast<size_t>(components) * i + 0];
+      images[1][i] = data[static_cast<size_t>(components) * i + 1];
+      images[2][i] = data[static_cast<size_t>(components) * i + 2];
+      if (components == 4) {
+        images[3][i] = data[static_cast<size_t>(components) * i + 3];
+      }
+    }
+  }
+
+  float *image_ptr[4] = {0, 0, 0, 0};
+  if (components == 4) {
+    image_ptr[0] = &(images[3].at(0));  // A
+    image_ptr[1] = &(images[2].at(0));  // B
+    image_ptr[2] = &(images[1].at(0));  // G
+    image_ptr[3] = &(images[0].at(0));  // R
+  } else if (components == 3) {
+    image_ptr[0] = &(images[2].at(0));  // B
+    image_ptr[1] = &(images[1].at(0));  // G
+    image_ptr[2] = &(images[0].at(0));  // R
+  } else if (components == 1) {
+    image_ptr[0] = &(images[0].at(0));  // A
+  }
+
+  image.images = reinterpret_cast<unsigned char **>(image_ptr);
+  image.width = width;
+  image.height = height;
+
+  header.num_channels = components;
+  header.channels = static_cast<EXRChannelInfo *>(malloc(
+      sizeof(EXRChannelInfo) * static_cast<size_t>(header.num_channels)));
+  // Must be (A)BGR order, since most of EXR viewers expect this channel order.
+  if (components == 4) {
+#ifdef _MSC_VER
+    strncpy_s(header.channels[0].name, "A", 255);
+    strncpy_s(header.channels[1].name, "B", 255);
+    strncpy_s(header.channels[2].name, "G", 255);
+    strncpy_s(header.channels[3].name, "R", 255);
+#else
+    strncpy(header.channels[0].name, "A", 255);
+    strncpy(header.channels[1].name, "B", 255);
+    strncpy(header.channels[2].name, "G", 255);
+    strncpy(header.channels[3].name, "R", 255);
+#endif
+    header.channels[0].name[strlen("A")] = '\0';
+    header.channels[1].name[strlen("B")] = '\0';
+    header.channels[2].name[strlen("G")] = '\0';
+    header.channels[3].name[strlen("R")] = '\0';
+  } else if (components == 3) {
+#ifdef _MSC_VER
+    strncpy_s(header.channels[0].name, "B", 255);
+    strncpy_s(header.channels[1].name, "G", 255);
+    strncpy_s(header.channels[2].name, "R", 255);
+#else
+    strncpy(header.channels[0].name, "B", 255);
+    strncpy(header.channels[1].name, "G", 255);
+    strncpy(header.channels[2].name, "R", 255);
+#endif
+    header.channels[0].name[strlen("B")] = '\0';
+    header.channels[1].name[strlen("G")] = '\0';
+    header.channels[2].name[strlen("R")] = '\0';
+  } else {
+#ifdef _MSC_VER
+    strncpy_s(header.channels[0].name, "A", 255);
+#else
+    strncpy(header.channels[0].name, "A", 255);
+#endif
+    header.channels[0].name[strlen("A")] = '\0';
+  }
+
+  header.pixel_types = static_cast<int *>(
+      malloc(sizeof(int) * static_cast<size_t>(header.num_channels)));
+  header.requested_pixel_types = static_cast<int *>(
+      malloc(sizeof(int) * static_cast<size_t>(header.num_channels)));
+  for (int i = 0; i < header.num_channels; i++) {
+    header.pixel_types[i] =
+        TINYEXR_PIXELTYPE_FLOAT;  // pixel type of input image
+
+    if (save_as_fp16 > 0) {
+      header.requested_pixel_types[i] =
+          TINYEXR_PIXELTYPE_HALF;  // save with half(fp16) pixel format
+    } else {
+      header.requested_pixel_types[i] =
+          TINYEXR_PIXELTYPE_FLOAT;  // save with float(fp32) pixel format(i.e.
+                                    // no precision reduction)
+    }
+  }
+
+  int ret = SaveEXRImageToFile(&image, &header, outfilename, err);
+  if (ret != TINYEXR_SUCCESS) {
+    return ret;
+  }
+
+  free(header.channels);
+  free(header.pixel_types);
+  free(header.requested_pixel_types);
+
+  return ret;
+}
+
+#ifdef __clang__
+// zero-as-null-ppinter-constant
+#pragma clang diagnostic pop
+#endif
+
+#endif  // TINYEXR_IMPLEMENTATION_DEFINED
+#endif  // TINYEXR_IMPLEMENTATION

Tools/Image/ImageImporterMain.cpp

@@ -17,6 +17,7 @@ Options:
 -store-raw <0|1>       : Store RAW images. Default is 0
 -mip-count <number>    : Max number of mipmaps. By default store until 4x4
 -astc-block-size <XxY> : The size of the ASTC block size. eg 4x4. Default is 8x8
+-verbose               : Verbose log
 )";
 
 static Error parseCommandLineArgs(int argc, char** argv, ImageImporterConfig& config,
@@ -161,6 +162,10 @@ static Error parseCommandLineArgs(int argc, char** argv, ImageImporterConfig& co
 
 			ANKI_CHECK(CString(argv[i]).toNumber(config.m_mipmapCount));
 		}
+		else if(CString(argv[i]) == "-verbose")
+		{
+			LoggerSingleton::get().enableVerbosity(true);
+		}
 		else
 		{
 			filenames.emplaceBack(filenames.getAllocator(), argv[i]);