Image decompression for the Jeilin JL2005B/C/D cameras
Herewith a general announcement that the long-mysterious decompression
algorithm needed to get photos out of the various cameras with the Jeilin
JL2005B, JL2005C, and JL2005D cameras has finally been conquered by a
sustained assault on the problem. The team which did this has consisted of
Adam, Bertrik, Hans, and myself.
A version of the decompression algorithm has been posted at
The above is a standalone decompression program, which will operate on
a raw file obtained from the camera by
and will emit an image in PPM format.
The affected cameras are those which are supported in the (still
experimental) libgphoto2/camlibs/jl2005c camera library.
Naturally, the code in playground/raw_converters/jl2005bcd_raw_converter
is intended for future inclusion in the camera library.
The affected cameras are those with the Vendor:Product combination
This ID is apparently used by all cameras with the JL2005B, JL2005C, and
JL2005D chip inside. There are at this point many of such cameras on the
I ask anyone who owns one of these cameras to try to get the raw photos
out and to test the decompressor program.
Congratulations again to the other members of the team which worked on
this project. The compression algorithm used for the photos in these
cameras is quite nasty to work on, and this problem has been lying around
for three years.