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<pre>
CarckArt *.CA1 (low resolution)
*.CA2 (medium resolution)
*.CA3 (high resolution)

1 word 'CA' crackart magic
1 byte compression: 00 = uncompressed, 01 = compressed
1 byte resolution: 00 = low res, 01 = medium res, 02 = high res
?? words palette
For low res pictures there are 16 palette entries
For med res pictures there are 4 palette entries
For high res pictures there are 0 palette entries
?? bytes Picture data:
For uncompressed pictures 32000 bytes follow
For compressed pictures the compressed data follows

-----------
< 32057 bytes total

CrackArt data compression:
1 byte Escape character
1 byte Delta: initially the 32000 screen memory are
filled with the delta byte
1 word Offset: offset between two packed bytes;
Offset is added to the current byte position
to calculate the next byte position. When the
next byte position is greater 32000, the next
byte position is the first position of screen
memory not written to
if Offset = 0, the whole screen if filled with
the delta byte, no packed bytes follow

1 byte Cmd: Command byte
Cmd <> Escape character: Cmd = one literal byte
Cmd = Escape charater:
read 1 control byte
0: read one byte, n, and one byte, b;
repeat b (n+1) times
1: read one word, n, and one byte, b;
repeat b (n+1) times
2: read one byte, if zero: stop else read
one extra byte and to make word n:
repeat Delta (n+1) times
Escape character: output one escape charater
else: read one byte, b;
repeat b cmd times
Decompression stops when Escape 2,0 is found or 32000 bytes have been written
</pre>
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CrackArt file format - Revision history

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