Beginning      Quantity                     Meaning
  ============    ========                    ============
     #0000        #30(16x3)      Palette. 16 triads of G,R,B colors
     encoded as ASCII digits:
                             "0"(#30) - color is off
                             "1"(#31) - dark color
                             "2"(#32) - normal color
                             "3"(#33) - bright color
                             Любое другое значение приравнивается
                             утилитой GRFVIEW к "3".

     #0030(*)     #03            "GRF"

     #0033(*)     #01            Recommended attribute for background
     (for small pictures)

     #0034(*)     #01            Recommended border (#00-#0F)

     #0035        #4B            Not used

     #0080(**)    #01            X-coord (0-79) of top left corner of
     the picture in bytes (=8 pixels)

     #0081(**)    #01            Y-coord (0-199) of top left corner of
     the picture in pixels

     #0082        #01            WIDTH (1..80) in bytes (=8 pixels)

     #0083        #01            HEIGHT (1..200) in pixels

     #0084     WIDTH*HEIGHT        Pixels. Column #0 (HEIGHT pixels) then
     column #1 ... column #(WIDTH-1).

#84+WIDTH*HEIGHT #nnnn          Attributes. The same but RLE encoded:
consists of pairs of bytes, in which the first byte in pair encodes number of repetitions of
second byte.


There are viewers of this format for CP/M (GRAF.COM), TASiS (grfview)
and TR-DOS (MCX viewer).

By now I should save the screenshot from RetroX when the picture is ready then cut
it in Photoshop, make 16 color palette and save the
picture in 8bpp format. Then I run my utility RetroXtoGRF
http://alonecoder.nedopc.com/zx/retroxtogrf.rar