galfar.imaginglib/Doc/VampyreDoc/FileFormats/Targa.xml

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<doc>
  <title>Truevision Targa File Format</title>
  <chapter>
    <title>Truevision Targa File Format</title>
    <par>
      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.
    </par>

    <table>
      <title>Targa File Format Support</title>
      <row>
        <th>Format</th>
        <th>TImageFormat equivalent</th>
        <th>Loading</th>
        <th>Saving</th>
      </row>
      <row>
        <td>8 bit indexed</td>
        <td><icode>ifIndex8</icode></td>
        <td>Yes</td><td>Yes</td>
      </row>
      <row>
        <td>8 bit grayscale</td>
        <td><icode>ifGray8</icode></td>
        <td>Yes</td><td>Yes</td>
      </row>
      <row>
        <td>16 bit ARGB</td>
        <td><icode>ifA1R5G5B5</icode></td>
        <td>Yes</td><td>Yes</td>
      </row>
      <row>
        <td>24 bit RGB</td>
        <td><icode>ifR8G8B8</icode></td>
        <td>Yes</td><td>Yes</td>
      </row>
      <row>
        <td>32 bit ARGB</td>
        <td><icode>ifA8R8G8B8</icode></td>
        <td>Yes</td><td>Yes</td>
      </row>
      <row>
        <td>All above but RLE compressed</td>
        <td><icode>-</icode></td>
        <td>Yes</td><td>Yes</td>
      </row>
      <row>
        <td>8 bit indexed Huffman, Delta, RLE</td>
        <td><icode>ifIndex8</icode></td>
        <td>No</td><td>No</td>
      </row>
      <row>
        <td>8 bit indexed Huffman, Delta, RLE, 4-pass</td>
        <td><icode>ifIndex8</icode></td>
        <td>No</td><td>No</td>
      </row>
    </table>

    <note>
      If anyone has some information about two last formats (TGA image type
      codes 32 and 33) please tell me.
    </note>

    <par>
      When working with Targa files you can find useful some options
      which can be set by <ref>SetOption</ref> function and their current values
      can be get by <ref>GetOption</ref> function.
      Or you can set them by modifying properties of <ref>TTargaFileFormat</ref>
      class.
    </par>

    <table>
      <title>Options Related to Targa Files</title>
      <row>
        <th>OptionId</th>
        <th>Allowed Values</th>
        <th>Usage</th>
      </row>
      <row>
        <td><ref>ImagingTargaRLE</ref></td>
        <td><b>0 (false)</b> or <b>1 (true)</b></td>
        <td>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 <b>0 (false)</b>. </td>
      </row>
    </table>

  </chapter>
</doc>