ComputerEyes Raw Data file format

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Revision as of 02:47, 30 January 2017 by Lp (talk | contribs) (corrected medium resolution bit ordering, based on PicSwitch)
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ComputerEyes Raw Data    *.CE1 (low resolution)
                         *.CE2 (medium resolution)
                         *.CE3 (high resolution)
                                
1 long          [$45594553 or "EYES"]
1 word          resolution [0 = low res, 1 = medium res, 2 = high res]
1 word          brightness adjust [0-191]
1 word          contrast adjust [0-191]
1 word          red adjust [0-191]
1 word          green adjust [0-191]
1 word          blue adjust [0-191]
1 word          ?
1 word          ?
1 word          ?
If resolution = 0 {
64000 bytes     red plane, 320 x 200, 1 pixel per byte
64000 bytes     green plane, 320 x 200, 1 pixel per byte
64000 bytes     blue plane, 320 x 200, 1 pixel per byte
------------
192022 bytes    total
} 
else If resolution = 1 {
128000 words    640 x 200, 1 pixel per word
------------
256022 bytes    total
} 
else if resolution = 2 {
256000 bytes    640 x 400, 1 pixel per byte
------------
256022 bytes    total
}

   This is almost three formats in one:
   
        Low resolution:

           The planes are arranged vertically, instead of horizontally.
        The first byte is the red component of pixel (0,0), the second is (0,1),
        and the third (0,2).  The 201st corresponds to (1,0), etc.  The 64001st
        byte is the green component of (0,0).
           Only the low six bits of each byte are used.

        Medium resolution:

           The picture is arranged vertically, instead of horizontally.
        The first word is pixel (0,0), the second is (0,1), and the third
        (0,2).  The 200th is (1,0) etc.
           Each word is divided up into the RGB values for the corresponding
        pixel, as follows:

          Bit:  (MSB) 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 (LSB)
                      -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
                       0 R4 R3 R2 R1 R0 G4 G3 G2 G1 G0 B4 B3 B2 B1 B0

        Bit 15 is not used.

        High resolution:
           
           The picture is arranged vertically, instead of horizontally.
        The first byte is pixel (0,0), the second is (0,2), and the third 
        (0,4). The 200th is (0,1), followed by (0,3), and (0,5), etc.
          Each byte represent a value from 0 to 191, which is the result
        of 6-bits each of R, G, and B added together, but not divided by 3.              

In order to reduce overhead the pixel arrangement matches the devices scanning 
sequence. It's also assumed the divide by 3 was left out of the high resolution
dump for the same reason. The re-arrangement of the pixels and the divide
could be done during post processing anyway.

These files are created by CE.PRG which comes with the ComputerEyes
hardware. It's not documented in the manual how to create these files.
You must hold down the Alternate key while clicking Save or Load in 
the File drop-down menu.

Further more the program PicSwitch v1.0.1 can process these files. This
feature is also not documented.

Indecently CE.PRG and PicSwith are both written by John Brochu.

Back to ST Picture Formats