Sun rasterfile image format

[Zoltan Levay]

Can someone explain to me the format of byte-encoded Sun rasterfiles
(ras_type == RT_BYTE_ENCODED).  I would like to know the structure of the
bytes in the file representing the pixels in the image.  I gather it's
some sort of run-length encoding, but it's not entirely obvious and I
can't seem to find the explanation in TFM.  I do understand the header,
colormap, and RT_STANDARD image formats.