[sane-devel] Canon LiDE 60: Semi-success report

[Henning Meier-Geinitz]

Hi,

On Mon, Dec 05, 2005 at 12:00:30AM +0100, Reinhard Mayr aka Czerwinski wrote:
> sorry, I did not realize that there is a difference between current CVS  
> and experimental.

Are you really sure that you use experimental now? :-)
Some of your errors occur for me with the normal CVS, but not with
experimental. Also, when you get an error, make sure you unplug and
replug the scanner when you do another test. Otherwise it may still be
confused by the earlier test.

Which frontend do you use? Is the scanner connected to a USB2 hub?

Just to be sure: xsane 0.98 does have a bug that can cause stack
corruption in the backend. While I didn't see this in connection with
the genesys backend, it happend with other backends. Try to use xsane
0.98b or apply the bug fix Oliver Rauch posted on this list.

I use xsane 0.98b for testing.

Details:

> gray/8bit:
> 75: ok
> 150: ok
> 300: ok
> 600: ok
> 1200: ok
> 2400: Error during read: error during device I/O. I can avoid this by  
> enforcing backtracking through system load (e.g. by task switching)

No backtracking here. No I/O errors. Image is ok but stretched in
Y-direction (as already mentioned in my report). You can enable
debugging this way:
SANE_DEBUG_GENESYS=255 SANE_DEBUG_GENESYS_GL841=255 xsane 2>log

The logs may be to big to be send to this list, however so please try
to compress them or place them on a website. The limit is 50 KB.

> gray/16bit:
> 75: ok
> 150: ok
> 300: ok
> 600: backtracking. horizontal lines

I only get backtracking here with high load of the computer.  However
I can confirm the horizontal lines. Looks like something connected to
backtracking at 16 bit doesn't fully work yet. I don't have
these lines in 8 bit mode.

This also happens with the Canon LiDE 50. Here is a sample image of
such a scan with forced backtracking (4.2 MB):
http://www.meier-geinitz.de/sane/tmp/lide50/stripes-16bit-gray-0600.png

> 1200: backtracking. Error during read: error during device I/O

No error here. I get some backtracking and one or several strange
horizontal lines when the scanner does backtracking. These lines
contain data from the scanned image but are horizontally moved
somehow. Data corruption?

> 2400: backtracking. horizontal lines - picture is unusable

Same here as for 1200 dpi.

> color/8bit:
> Segmentation fault at any resolution

Works for me. Backtracking in high resolutions, but no stripes.
Please create a log file and run the frontend in gdb and do a
backtrace there (bt) when the error occurs.

> color/16bit:
> 600: Failed to start scanner: invalid argument
> other resolutions: segmentation fault

Works for me. No stripes even when backtracking with the Canon LiDE
60. However, I do get some stripes with the Canon LiDE 50. So there is
a backtracking problem in 16 bit mode (3.5 MB):

http://www.meier-geinitz.de/sane/tmp/lide50/stripes-16bit-color-0300.png

Bye,
  Henning