[sane-devel] Problems with Canon MP990 transparency unit

Tue Nov 11 17:32:38 UTC 2014

Hi,

Progress here ! It turns out MP990 needs Data[0x25]=0x01 like some other 
scanners.
Sadly, I now have a color problem, white is greenish. Is that a gamma 
table problem ?

Bye.

Le 09/11/2014 21:12, Guillaume Courtois a écrit :
> Hi,
> 
> Worked a few hours again on the problem. It seems like I don't get the
> correct datas from the scanner (or it's being badly post-processed)
> when I'm using bigger resolutions than 300 dpi with TPU unit. Flatbed
> seems all ok.
> 
> 300 dpi scans do not give me underruns, but all the others do, and
> with bigger and bigger values. The resulting pictures are bigger and
> bigger in size, but the image inside them is worse : it seems like the
> bigger the resolution I choose, the less I get actual lines of datas.
> 
> Again, if you have any ideas, that would be cool. I can provide datas,
> logs, whatever you want.
> 
> Thanks guys.
> 
> Bye.
> 
> Le 02/11/2014 16:47, Guillaume Courtois a écrit :
>> Hi Rolf,
>> 
>> I've just seen I sent my first response to you but not the list, sorry
>> about that (but it contained nothing interesting in fact).
>> 
>> I made some progress today, color shifting seem ok and I don't have
>> the white columns anymore.
>> I'll have to give a clean patch to the list for that, but first I have
>> to solve my last problem, which is underrun.
>> 
>> I tried to find the source of that problem but with no luck until now.
>> It seem to happen only with TPU unit, strange ?
>> 
>> Here is the result at 1200 dpi :
>> 
>> pixma] **mp810_fill_buffer***** end of image *****
>> [pixma] WARNING:image size mismatches
>> [pixma]     859431936 expected (14032 lines) but 222452736 received 
>> (3632 lines)
>> [pixma] pixma_read_image(): completed (underrun detected)
>> 
>> (in debug :
>> [pixma] *mp810_fill_buffer***** moving 504704 bytes into buffer *****
>> [pixma] *mp810_fill_buffer***** 507904 bytes received by 
>> read_image_block *****
>> )
>> 
>> and at 600 dpi :
>> 
>> [pixma] **mp810_fill_buffer***** end of image *****
>> [pixma] WARNING:image size mismatches
>> [pixma]     214857984 expected (7016 lines) but 111226368 received 
>> (3632 lines)
>> [pixma] pixma_read_image(): completed (underrun detected)
>> 
>> (in debug :
>> [pixma] *mp810_fill_buffer***** moving 260096 bytes into buffer *****
>> [pixma] *mp810_fill_buffer***** 245760 bytes received by 
>> read_image_block *****
>> )
>> 
>> Buffer size seem to be twice the size when raising the resolution.
>> Shouldn't it be 4 times bigger ?
>> 
>> I hope you have an idea here because my head is exploding...
>> 
>> Thanks !
>> 
>> Bye.
>> 
>> Le 27/10/2014 16:57, Rolf Bensch a écrit :
>>> Hi Guillaume,
>>> 
>>> If you want to dig into the source code, you can look here:
>>> 
>>> file: pixma_mp810.c
>>> function: post_process_image_data()
>>> 
>>> It's possible that post processing image data is broken. Please check
>>> these git commits:
>>> b4bb0062c5cbb77c895b439b5f47e70b506305b1 (2013-01-11 16:37:00) and
>>> 1da5bcc2aa16a6382e5bd78a47cb3ec222a9aafc (2012-01-15 03:48:19)
>>> 
>>> Many thanks for your help.
>>> 
>>> Cheers,
>>> Rolf
>>> 
>>> 
>>> Am 19.10.2014 um 15:20 schrieb Guillaume Courtois:
>>>> 
>>>> Hi guys,
>>>> 
>>>> I'm currently trying to make the TPU correctly work on my MP990
>>>> scanner. It seems like there are shifting problems both in datas and
>>>> in the 3 colors (which seem to be 2 separate issues, but not sure).
>>>> 
>>>> I'm currently testing on my debian SID with sane GIT version, but I
>>>> have tested packages from SID and made tests on a Mint 17 netbook
>>>> also. All seem to give the same results.
>>>> 
>>>> It seems like datas are not shifted in 300 dpi but are more and more
>>>> shifted when you choose higher resolutions (600, 1200, 2400 dpi).
>>>> 
>>>> I'm happy to provide pictures if you want to see what it gives, but
>>>> that gives vertical black stripes on the captured picture.
>>>> 
>>>> Here is the output of xscanimage with some debug activated :
>>>> 
>>>> Here is the 300 dpi correct scan :
>>>> 
>>>> [pixma] pixma_scan(): start
>>>> [pixma]   line_size=3378 image_size=9674592 channels=3 depth=16
>>>> [pixma] Reader task id=140539733346048 (threaded)
>>>> [pixma]   dpi=300x300 offset=(780,88) dimension=563x2864
>>>> [pixma]   gamma_table=0xd939e0 source=2
>>>> [pixma]   threshold=127 threshold_curve=0
>>>> [pixma]   ADF page count: 0
>>>> [pixma] Setting non-blocking mode
>>>> [pixma] Current status: paper=0 cal=0 lamp=2 busy=0
>>>> [pixma] Current status: paper=0 cal=0 lamp=2 busy=0
>>>> [pixma] Current status: paper=0 cal=0 lamp=2 busy=0
>>>> [pixma] Lamp status: 3 , timeout in: 19
>>>> [pixma] pixma_read_image():completed
>>>> [pixma] Reader task terminated
>>>> [pixma] Reader task started
>>>> [pixma] Reader task id=140539733346048 (threaded)
>>>> 
>>>> Here is the not-so-correct 1200 dpi scan :
>>>> 
>>>> [pixma] pixma_scan(): start
>>>> [pixma]   line_size=13938 image_size=67376292 channels=3 depth=16
>>>> [pixma]   dpi=1200x1200 offset=(282,446) dimension=2323x4834
>>>> [pixma]   gamma_table=0xd939e0 source=2
>>>> [pixma]   threshold=127 threshold_curve=0
>>>> [pixma]   ADF page count: 0
>>>> [pixma] Setting non-blocking mode
>>>> [pixma] Current status: paper=0 cal=0 lamp=2 busy=0
>>>> [pixma] Current status: paper=0 cal=0 lamp=2 busy=0
>>>> [pixma] Current status: paper=0 cal=0 lamp=2 busy=0
>>>> [pixma] Lamp status: 3 , timeout in: 19
>>>> [pixma] WARNING:image size mismatches
>>>> [pixma]     67376292 expected (4834 lines) but 44044080 received 
>>>> (3160
>>>> lines)
>>>> [pixma] pixma_read_image(): completed (underrun detected)
>>>> 
>>>> As you can see, mismatch and underrun tells me I have to dig around 
>>>> that.
>>>> 
>>>> Also, it seems like data coming from the preview window is
>>>> mis-interpreted : I have to pick a smaller and decaled window in 
>>>> order
>>>> to get the actual correct part of the scan I want to have (I don't
>>>> know if I'm pretty clear on that one ?).
>>>> 
>>>> I'm still digging into the code to see if I can correct that but if
>>>> you guys could point me to the right direction, that would save me
>>>> lots of time.
>>>> 
>>>> Thanks for your attention, keep up the nice work on sane !
>>>> 
>>>> Bye.
>>>> 
>>>> 