[sane-devel] Epson Perfection 3490 -> included bugfix makes it work

[Julien BLACHE]

"Belgabor" <belgabor at gmx.de> wrote:

> I also have to thank for this patch (it came on the day I boght the scanner
> without knowing about the issues). It is almost perfect as it works nice for
> resolutions up to 1200 dpi. At 2400 and 3200 I get a combing effect. Every
> other pixel column is offset by several pixels. It looks a bit like an
> interlaced PAL TV picture (only the combing is vertical rather than
> horizontal). 
> Hints appreciated (also if someone could confirm this. The error isn't there
> in windoze, so it doesn't seem to be a hardware problem).

The backend needs to perform line distance correction on the image as
for the 2480/2580 and an increasing number of scanners.

The high resolution are obtained by combining the data from 2 slightly
offset sensors (lower resolution, cheaper), hence the offset you see.

JB.

-- 
Julien BLACHE                                   <http://www.jblache.org> 
<jb at jblache.org>                                  GPG KeyID 0xF5D65169