PaintShop file format
PaintShop plus *.PSC (st high resolution) *.DA4 (st high resolution, double height) *.DA4 files are simple screen dumps: 64000 bytes image data (uncompressed, thus 640x800) ----------- 64000 bytes total for file *.PSC files are compressed: 6 bytes file id ["tm89PS"] 1 word version [0xCB = 2.03] 1 byte ? [always 2] 1 byte ? [always 1] 1 word image width in pixels - 1 [always 639] 1 word image height in pixels - 1 [always 399] -------- 14 bytes total for header ? image data: The image data is not compressed based on pixels, but rather scan lines. Starting at the top and working downward. There are 9 unique codes: Codes: 0 set current line all white (0x00) 10 copy line above (next byte + 1) times 12 copy line above (next byte + 256 + 1) times 99 copy from stream 80 * 400 lines (full image) 100 fill next line with (next byte) as line style [(b << 8 ) | b] 102 fill next line with (next 2 bytes) as line style [(b1 << 8) | b2] 110 copy from stream 80 bytes to current line 200 set current line all black (0xFF) 255 marks end of file (stop process codes) 'line style' mentioned above is a reference to VDI function vsl_udsty(), set user-defined line style pattern. Essentially, fill that line with the bit pattern.
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