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

Wed Mar 16 21:11:17 UTC 2016

My patch did not change anything about 240dpi, since you said that was
already working. I think perhaps there is something else going on
here. Can you power cycle the scanner after each test?

allan

On Wed, Mar 16, 2016 at 1:45 PM, el-ti <tl at ewetel.net> wrote:
> 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
>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> --
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>>>>>>>>>>>> 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"
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>
>>
>>
>>

-- 
"well, I stand up next to a mountain- and I chop it down with the edge
of my hand"