[sane-devel] bug with Canon N1240U in Lineart mode at 75 dpi?

Gerhard Jaeger gerhard@gjaeger.de
Tue, 30 Nov 2004 08:14:51 +0100


On Saturday 27 November 2004 20:24, Eric Ding wrote:
> I'm using sane-backends 1.0.15 with libusb on Gentoo Linux with a Canon
> N1240U scanner.
> When I try to scan in Lineart mode at 75dpi, I get a few back-and-forth
> pauses, then a significant buzzing sound as the scanner's (green) light
> is on, but the light bar doesn't move at all.  Scanning in other modes
> (i.e., Gray, Color) or in Lineart mode with higher resolutions (i.e.,
> 96, 300, etc.) works fine.
> Scanning with these settings using Canon's Windows driver works, so I
> conclude that this is likely an issue with the SANE plustek backend.
> Below find the stderr output of running
>      scanimage --mode Lineart --resolution=75
> with SANE_DEBUG_PLUSTEK set to 13. Have I found a bug? Can anyone
> confirm or deny this behavior?
> Thanks,
> Eric

I've tested that here and have no problems so far. It might be, that the 
motor settings for this mode are somewhat at or slightly beyond the limit
so that some devices have no problems while others have...
Can you do some more tests, i.e. increase the resolution and check when it's