[sane-devel] Canon FS4000: image data is sensor data, not RGB?

Dave Burns sane@burnsorama.com
Thu, 17 Jun 2004 11:59:18 -0400

I am making good progress reverse-engineering the SCSI protocol for this
film scanner. I now have a short test program in C that scans film and I now
have the challenge of decoding the image data returned. It appears to be raw
sensor data. I don't have experience with many other scanners: is this
typical of scanners to return raw data? Or maybe typical of film scanners
but not flatbed?

I have seen Dave Coffin's page on dcraw
(http://www.cybercom.net/~dcoffin/dcraw/) which can decode sensor data to
RGB but want to consult this list before I start to integrate his code in
case anyone here has already done this and can offer tips/advice.

Also, the image data appears to contain more data than expected. I.e. there
is more data then there should be if I consider the size of my scanning
window and work out the math. Is this typical and is it normal to have to
interpolate to provide the user with expected results?