Problem is I'm not sure where the pixel data comes from. It's in row-major order, one byte per pixel. It's NOT greyscale. I'm presuming it's using a lookup table or color palate or something.
Quite likely, it's an 8-bit index into the standard MacOS system color table--the one used if you create a GIF image and use the Macintosh color palette.
So it's essentially like a GIF, except that it is not LZW compressed and it does not have the color lookup table built in.
