Truevision defined the TGA file format in 1984 for use with its first videographics products. It was the first truecolor file format widely available. They are still widely used for images with alpha channels. It can store indexed, grayscale, RGB and ARGB images. Targas can be uncompressed or compressed with RLE (run length encoding) algorithm.

Format	TImageFormat equivalent	Loading	Saving	8 bit indexed	ifIndex8	Yes	Yes	8 bit grayscale	ifGray8	Yes	Yes	16 bit ARGB	ifA1R5G5B5	Yes	Yes	24 bit RGB	ifR8G8B8	Yes	Yes	32 bit ARGB	ifA8R8G8B8	Yes	Yes	All above but RLE compressed	-	Yes	Yes	8 bit indexed Huffman, Delta, RLE	ifIndex8	No	No	8 bit indexed Huffman, Delta, RLE, 4-pass	ifIndex8	No	No

If anyone has some information about two last formats (TGA image type codes 32 and 33) please tell me. When working with Targa files you can find useful some options which can be set by SetOption function and their current values can be get by GetOption function. Or you can set them by modifying properties of TTargaFileFormat class.

OptionId	Allowed Values	Usage	ImagingTargaRLE	0 (false) or 1 (true)	Indicates whether Targa image will be saved with or without RLE compression (efficient only for images with large areas of the same color). Default value is 0 (false).