Calamus Raster Graphic file format

Calamus Raster Graphic    *.CRG

10 bytes        file id [”CALAMUSCRG”]
1 word          version? [$03E8]
1 word          version? [$0002]      
1 long          file size, minus 24
1 word          code for the page size? [$0080]
1 long          image width in pixels
1 long          image height in pixels
1 long          unknown [varies]
1 byte          unknown [$01]
1 byte          unknown [$00]
1 long          unknown [$FFFFFFFF]
1 long          size of compressed image data in bytes
--------
42 bytes        total for header

??              monochrome image adata

RLE compression scheme: The compressed data consists of a code byte, followed by one or 
more data bytes, followed by another code byte, and so on. 
  
  To decompress:  Code byte (N)    Instructions
                  N <= 127         Emit the next N+1 bytes literally.
                  N >= 128         Emit the next byte N-127 times.
                  
  After decompression, pixels are in left-to-right, top-to-bottom order. The format is
  8 pixels per byte, most significant bit first, white is 0. Rows are padded to the next
  byte boundary.

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