GEOpaint File Format

               GEOpaint  files  are  VLIR  structured  files.  Each  branch
          represents  2 lines of the picture.  The data in the branches  is
          stored  in a coded form that is different from photo  scraps  and
          click  boxes.  First  of  all,  consecutive bytes do not  form  a
          horizontal  line.  The  bytes  are in the same  sequence  as  the
          Commodore  stores  them on the hires  screen.  Eight  consecutive
          bytes fill a character position. Every eighth byte is on the same
          horizontal line.  

          640 bytes bitmapped for row #(RECORD# * 2) + 1 (80 cards * 8 bytes)          
          640 bytes bitmapped for row #(RECORD# * 2) + 2 (80 cards * 8 bytes)
          81st card byte = 8 zero bytes?!?!
          80 bytes color info for row #(RECORD# * 2) + 1 (80 cards * 1 byte)
          80 bytes color info for row #(RECORD# * 2) + 2 (80 cards * 1 byte)

          The bitmap data is stored in a coded form to conserve disk storage.
          The coding is simply a code byte followed by some data. Code bytes 
          fall into one of the following three categories:

               1) Code   bytes  less  than  64  determine  the  number   of
                  individual bytes that follow.
               2) Code  bytes  ranging  from 64 to 127 are  used  for  fill
                  patterns. The least significant 6 bits determine how many
                  character  positions are to be filled.  This code byte is
                  followed by eight bytes which determine the fill pattern.
               3) Code  bytes greater than 127 are 128 more than the number
                  of times to repeat the byte that follows the code byte.

          This  coding scheme is used to first specify the 1280 bytes  that
          form  the two lines of the picture. This is followed by  the  160
          bytes which form the color data for the two lines.  Each of these
          bytes is split into two four-bit nybbles.  The higher-order nybble
          (bits 7-4) specify the color of the foreground in that card while
          the lower order nybble (bits 3-0) specify the background color for
          that card.