https://www.temlib.org/AtariForumWiki/index.php?action=history&feed=atom&title=Canvas_file_formatCanvas file format - Revision history2026-05-13T17:43:50ZRevision history for this page on the wikiMediaWiki 1.39.2https://www.temlib.org/AtariForumWiki/index.php?title=Canvas_file_format&diff=11689&oldid=prev>Lp: moved Canvas to Canvas file format: Renamed so "Canvas" app page can be used in the future2017-01-02T22:40:20Z<p>moved <a href="/AtariForumWiki/index.php/Canvas" class="mw-redirect" title="Canvas">Canvas</a> to <a href="/AtariForumWiki/index.php/Canvas_file_format" title="Canvas file format">Canvas file format</a>: Renamed so "Canvas" app page can be used in the future</p>
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<p><b>New page</b></p><div><pre><br />
Canvas *.CNV, *.CPT<br />
<br />
Canvas is a simple drawing program for the Atari ST. The simplest file<br />
format it uses is .CNV. The format has no infor on the resolution of <br />
the image. The colors are stored in VDI order.<br />
<br />
48 bytes palette, value 0-7 per byte, RGB in VDI order.<br />
32000 bytes image data<br />
<br />
<br />
The CPT format is a compressed format:<br />
16 words palette<br />
1 word resolution (0=low, 1=med, 2=high resolution)<br />
??? words compressed data, uncompressed 32000 bytes<br />
<br />
Packing algorithm: first all runlength data is transfered. Then the<br />
gaps that haven't been filled with runlengthdata is filled with the <br />
remaining data from file.<br />
Runlength data:<br />
1 word repeat count<br />
1 word offset<br />
n words run length data (n=4 low, 2 med, 1 high)<br />
The n words run length data are repeated (repeat count +1) times from <br />
offset bytes from the start of the file. When repeat count $FFFF signifies <br />
the end of the run length data (the offset and run length data still folow <br />
the $FFFF repeat count).<br />
??? words data to fill the gaps that haven't been filled with run <br />
length data.<br />
</pre><br />
Back to [[ST Picture Formats]]</div>>Lp