Difference between revisions of "TruePaint/Prism Paint file format"

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                           24 bit is stored R, G, B in that order
 
                           24 bit is stored R, G, B in that order
  
−
The prism paint compressed format uses the packbits compression algorithm. For every  
+
The prism paint compressed format uses the Packbits compression algorithm. For every  
 
scanline the bitplanes are compressed separately. The falcon high-color resolution  
 
scanline the bitplanes are compressed separately. The falcon high-color resolution  
 
(16 bit) is compressed as if there were 16 bitplanes, which there are not.
 
(16 bit) is compressed as if there were 16 bitplanes, which there are not.
 
The same rule applies to 24 bits per pixel.
 
The same rule applies to 24 bits per pixel.
 +
 +
Additional information:
 +
The TruePaint manual describes the format as designed for high speed and only writes
 +
uncompressed files. Prism Paint on the other hand offers compression every time a
 +
file is saved with an alert box (yes/no).
 
</pre>
 
</pre>
 
See also [[PackBits Compression Algorithm]]
 
See also [[PackBits Compression Algorithm]]
  
 
Back to [[ST Picture Formats]]
 
Back to [[ST Picture Formats]]

Latest revision as of 01:14, 4 June 2018

TruePaint       *.TPI
Prism Paint     *.PNT

  1 long        $504e5400 'PNT\0' TruePaint Magic
  1 word        $0100             ???? file version
  1 word        palette_size      Might be there in true color
  1 word        x_size
  1 word        y_size
  1 word        bits_per_pixel
  1 word        compression, $0000 uncompressed, $0001 packbits compressed
  1 long        picture_data_size = ((x_size+15)&0xffff0)*y_size*bits_per_pixel/8 
                (uncompressed)
108 bytes       $0
---------
128 bytes       total for header

3*palette_size     words   Palette data, RGB, values 0..1000. The colors are in VDI order
                          
picture_data_size  bytes   The line length is a multiple of 16 pixels for all bit depths
                           Interleaved bitplanes for bits_per_pixel<16
                           16 bit word per pixel for 16-bit pictures, RRRRrGGGGGgBBBBBb
                           24 bit is stored R, G, B in that order

The prism paint compressed format uses the Packbits compression algorithm. For every 
scanline the bitplanes are compressed separately. The falcon high-color resolution 
(16 bit) is compressed as if there were 16 bitplanes, which there are not.
The same rule applies to 24 bits per pixel.

Additional information:
The TruePaint manual describes the format as designed for high speed and only writes
uncompressed files. Prism Paint on the other hand offers compression every time a
file is saved with an alert box (yes/no).

See also PackBits Compression Algorithm

Back to ST Picture Formats