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| | <code>.dg1</code> files begin with ASCII "{{magic|DGU}}". | | <code>.dg1</code> files begin with ASCII "{{magic|DGU}}". |
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| − | <pre>
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| − | PaintShop plus *.PSC (st high resolution)
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| − | *.DA4 (st high resolution, double height)
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| − |
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| − | *.DA4 files are simple screen dumps:
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| − |
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| − | 64000 bytes image data (uncompressed, thus 640x800)
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| − | -----------
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| − | 64000 bytes total for file
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| − |
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| − | *.PSC files are compressed:
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| − |
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| − | 6 bytes file id ["tm89PS"]
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| − | 1 word version [0xCB = 2.03]
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| − | 1 byte ? [always 2]
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| − | 1 byte ? [always 1]
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| − | 1 word image width in pixels - 1 [always 639]
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| − | 1 word image height in pixels - 1 [always 399]
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| − | --------
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| − | 14 bytes total for header
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| − |
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| − | ? image data:
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| − | The image data is not compressed based on pixels, but rather scan lines. Starting at the
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| − | top and working downward. There are 9 unique codes:
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| − |
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| − | Codes:
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| − | 0 set current line all white (0x00)
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| − | 10 copy line above (next byte + 1) times
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| − | 12 copy line above (next byte + 256 + 1) times
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| − | 99 copy from stream 80 * 400 lines (full image)
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| − | 100 fill next line with (next byte) as line style [(b << 8 ) | b]
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| − | 102 fill next line with (next 2 bytes) as line style [(b1 << 8) | b2]
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| − | 110 copy from stream 80 bytes to current line
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| − | 200 set current line all black (0xFF)
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| − | 255 marks end of file (stop process codes)
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| − |
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| − | 'line style' mentioned above is a reference to VDI function vsl_udsty(), set user-defined
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| − | line style pattern. Essentially, fill that line with the bit pattern.
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| − | </pre>
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| | | | |
| | == Software == | | == Software == |
Revision as of 20:47, 10 August 2020
DuneGraph is a graphics program for the Atari ST line of computers. .dc1 files are compressed .dg1 files.
Identification
.dc1 files begin with ASCII "DGC".
.dg1 files begin with ASCII "DGU".
Software
Sample files
Links
