[sane-devel] HP Scanjet 3670 bad colors

[Octavio Alvarez]

Hi.

I'm trying to get my HP Scanjet 3670 under Linux. The scanner works (it
scans and all) but the scan has some color distortion.

I confirmed the scanner works: here is a comparison of a section of a
scanned image in both, Windows and Linux:

http://blog.alvarezp.org/files/scan-hp3670/scan-hp3670-win7.jpg
http://blog.alvarezp.org/files/scan-hp3670/scan-hp3670-linux.png

The scan is a black and white section of a creased document.

Even the problem itself is very unstable. Sometimes the whole page is
distorted, sometimes only gray shades are. *Once* in my 40-like attempts
the output was acceptable but I could not reproduce this success case. I
noticed, though that solid strong colors are usually not distorted.

I wanted to find out if this was an introduced bug, but I could only
compile as back as 1.0.22 + 2 commits and it failed too. Before that,
there is a V4L compilation blocker that prevented me from going further
back.

I tried looking at the code but I realized I understand very little
(near to nothing) about how a scanner works.

Is this a SANE bug? What can be done to make it properly work?

Thanks.