[sane-devel] Canon DR-C125: Wrong colors when scanning Duplex

Wed Mar 16 17:45:12 UTC 2016

Oh! Mea culpa – I missed that point. But now the scanner works again,
and the behavior changed!  – That’s the good news. Not so good news is,
that now I have the following:

Resolutions 300 and 600 have the right colors.

Scanning with 100,150, 200 and 400 is now:
Blue -> Green
Green -> Red
Red -> Blue

Scanning with 240 is now:
Blue -> Red
Red -> Green
Green -> Blue

I don’t know if it helps, but I created a pdf document with scans in
color mode of the same page with the different resolutions in ascending
order: 100,150,200,240,300,400,600

You can get it here:
https://de.owncube.com/index.php/s/KaSuVc4vRFWdOk4

What you can also see there, is that there is a color strip on the left
side and that the page is a bit shifted horizontally – but this is not
our discussed problem at the moment.

I hope this helps you.

Thanks!
el-ti

Am 16.03.2016 um 15:01 schrieb m. allan noah:
> Did you install libusb-devel before you compiled sane-backends?
> 
> allan
> 
> On Wed, Mar 16, 2016 at 9:29 AM, el-ti <tl at ewetel.net> wrote:
>> All right, I’m pretty sure I got everything right, but surprisingly the scanner is not detected anymore... ("scanimage -L" only gives back the internal notebook camera) – is it even possible, that this is caused by the steps above? Or did I do something wrong?
>>
>> Sorry for all the work…
>>
>>
>> Am 16.03.2016 um 13:24 schrieb m. allan noah:
>>> 1. Download sane-backends-git snapshot from:
>>> http://www.sane-project.org/snapshots/
>>>
>>> 2. In a terminal, cd to the directory where you downloaded the file
>>> (perhaps ~/Downloads)
>>> cd ~/Downloads
>>>
>>> 3. Extract the file (update name as required)
>>> tar xzf sane-backends-gitXXXXXXXX.tar.gz
>>>
>>> 4. Change into the source directory (update name as required)
>>> cd sane-backends-gitXXXXXX/
>>>
>>> 5. Apply the patch (update location as required, perhaps also ~/Downloads)
>>> cat ~/Downloads/cdr-55a.diff | patch -p1
>>>
>>> 6. Then you need to follow the instructions at
>>> http://www.sane-project.org/README.linux That will have you installing
>>> an updated version of sane-backends in /usr/local, where it has a
>>> reduced change of causing problems for your system.
>>>
>>> Let me know if you have questions.
>>>
>>> allan
>>>
>>> On Wed, Mar 16, 2016 at 6:38 AM, el-ti <tl at ewetel.net> wrote:
>>>> Thank you very much for your work.
>>>>
>>>> Unfortunately, I have no experience with patching something like this so far. I did some research, though – seems to be quite doable. I’m familiar with the terminal etc. As I understand this, I have to apply the diff-file on the original file with the patch command. So far, so good – but I have no idea, which file it is. I couldn’t figure out by looking at the diff file.
>>>>
>>>> If you could tell, on which file I have to apply this, that would be great! Thanks!
>>>>
>>>> Tobias
>>>>
>>>>
>>>> Am 16.03.2016 um 01:33 schrieb m. allan noah:
>>>>> I have attached a patch for the sane-backends source code. This
>>>>> attempts to provide alternate color de-interlacing for your scanner.
>>>>> It does not attempt to fix any edge cropping issues. Let me know if
>>>>> you need more instructions.
>>>>>
>>>>> allan
>>>>>
>>>>> On Tue, Mar 15, 2016 at 7:59 PM, m. allan noah <kitno455 at gmail.com> wrote:
>>>>>> Canon scanners often have this variable interlacing at different
>>>>>> resolutions, so I am not surprised to see this. However, this
>>>>>> particular scanner has the weirdest interlacing that canon does. If
>>>>>> you can compile from source, I can send you some patches to try. See
>>>>>> http://www.sane-project.org/README.linux
>>>>>>
>>>>>> allan
>>>>>>
>>>>>> On Tue, Mar 15, 2016 at 9:17 AM, el-ti <tl at ewetel.net> wrote:
>>>>>>> Unfortunately, yes.
>>>>>>>
>>>>>>> I uninstalled "cndrvsane-drc125" and restartet the system. The color shift is still there.
>>>>>>>
>>>>>>> And there is also the problem, that there is a 1/2 cm cut on the long edge of the scanned page (the "duplex-offset" option only handles the short edge) – but I guess this is another problem.
>>>>>>>
>>>>>>> If you need more information, do not hesitate to tell me.
>>>>>>>
>>>>>>> el-ti
>>>>>>>
>>>>>>> Am 15.03.2016 um 12:41 schrieb m. allan noah:
>>>>>>>> If you uninstall the Canon "DR-C125 Driver for Linux V1.0 (v1.0)"
>>>>>>>> software, does this color shift still happen?
>>>>>>>>
>>>>>>>> allan
>>>>>>>>
>>>>>>>> On Tue, Mar 15, 2016 at 7:37 AM, el-ti <tl at ewetel.net> wrote:
>>>>>>>>> The system is using the libsane version from the PPA: 1.0.26-git20160305-wily0
>>>>>>>>>
>>>>>>>>> It was installed above the one from Ubuntu’s repositories, when I added the PPA.
>>>>>>>>>
>>>>>>>>> el-ti
>>>>>>>>>
>>>>>>>>> Am 15.03.2016 um 12:22 schrieb m. allan noah:
>>>>>>>>>> You have installed both sane-backends, and canon's driver? Which one
>>>>>>>>>> are you using? Assuming you are actually using sane-backends, we will
>>>>>>>>>> have to modify the code to control the color descrambling.
>>>>>>>>>>
>>>>>>>>>> allan
>>>>>>>>>>
>>>>>>>>>> On Tue, Mar 15, 2016 at 6:08 AM, el-ti <tl at ewetel.net> wrote:
>>>>>>>>>>> Hello,
>>>>>>>>>>>
>>>>>>>>>>> I have an appendix to make – maybe someone has a hint for me, why the
>>>>>>>>>>> scanner behaves really strange:
>>>>>>>>>>>
>>>>>>>>>>> Depending on the scanning resolution, the shifting on the color range is
>>>>>>>>>>> different! I used the following command to test this:
>>>>>>>>>>>
>>>>>>>>>>> scanimage --batch --source "ADF Duplex" --page-width 210
>>>>>>>>>>> --page-height=297 -l 0 -t 0 -x 210 -y 297 --mode Color --resolution 300
>>>>>>>>>>>
>>>>>>>>>>> Then I tried all available resolutions: 100, 150, 200, 240, 300, 400,
>>>>>>>>>>> 600. The results are strange:
>>>>>>>>>>>
>>>>>>>>>>> Scanning with 100,150,200 gives me:
>>>>>>>>>>> Blue -> Red
>>>>>>>>>>> Red -> Green
>>>>>>>>>>> Green -> Blue
>>>>>>>>>>>
>>>>>>>>>>> Scanning with 300 and 400 gives me:
>>>>>>>>>>> Blue -> Green
>>>>>>>>>>> Green -> Red
>>>>>>>>>>> Red -> Blue
>>>>>>>>>>>
>>>>>>>>>>> And scanning with 240 and 600 shows the RIGHT colors.
>>>>>>>>>>>
>>>>>>>>>>> How is that possible? And how can this problem be solved?
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> I installed Rolf Bensch’s PPA
>>>>>>>>>>> (https://launchpad.net/~rolfbensch/+archive/ubuntu/sane-git), because it
>>>>>>>>>>> solved the back page cutting problem when scanning Duplex. (see
>>>>>>>>>>> http://permalink.gmane.org/gmane.comp.graphics.scanning.sane.devel/24903)
>>>>>>>>>>>
>>>>>>>>>>> Other than that, I only installed the Canon "DR-C125 Driver for Linux
>>>>>>>>>>> V1.0 (v1.0)".
>>>>>>>>>>>
>>>>>>>>>>> Any hint is appreciated!
>>>>>>>>>>> el-ti
>>>>>>>>>>>
>>>>>>>>>>> Am 04.03.2016 um 10:59 schrieb el-ti:
>>>>>>>>>>>> Dear Sane-developers and users,
>>>>>>>>>>>>
>>>>>>>>>>>> through this very helpful discussion
>>>>>>>>>>>> (http://permalink.gmane.org/gmane.comp.graphics.scanning.sane.devel/24903),
>>>>>>>>>>>> I managed to get my Canon Scanner working in Duplex without cutting 1 cm
>>>>>>>>>>>> of the back page.
>>>>>>>>>>>>
>>>>>>>>>>>> Everything seems to work fine. However, I discovered a very strange
>>>>>>>>>>>> behaviour regarding the colour management: When scanning in simplex
>>>>>>>>>>>> mode, everything works fine. There is no page cutting and colours are as
>>>>>>>>>>>> they should be. But in duplex mode, the colours are somehow shifted on
>>>>>>>>>>>> the colour range: Blue is scanned as green, green is scanned as red, red
>>>>>>>>>>>> is scanned as blue (for both back and front page).
>>>>>>>>>>>>
>>>>>>>>>>>> Is there an easy solution for this? Or did I forget to install something?
>>>>>>>>>>>>
>>>>>>>>>>>> Thank you very much!
>>>>>>>>>>>> el-ti
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> --
>>>>>>>>>>> sane-devel mailing list: sane-devel at lists.alioth.debian.org
>>>>>>>>>>> http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/sane-devel
>>>>>>>>>>> Unsubscribe: Send mail with subject "unsubscribe your_password"
>>>>>>>>>>>              to sane-devel-request at lists.alioth.debian.org
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> "well, I stand up next to a mountain- and I chop it down with the edge
>>>>>> of my hand"
>>>>>
>>>>>
>>>>>
>>>>
>>>
>>>
>>>
>>
> 
> 
> 