[sane-devel] Problems with Canon MP990 transparency unit

Rolf Bensch rolf at bensch-online.de
Sat Nov 15 13:16:46 UTC 2014


Hi Guillaume,

Please set me on CC when you respond to the mailing list. I missed your
last emails.

If possible, please fetch the usb traffic on a Windows machine for a tpu
scan. Then we can investigate the correct settings for the scan
parameters command.

On the other hand it seems that your scanner has problems with image
post processing @ higher resolutions. Please scan a small detail of an
image for all resolutions and save them as pnm/png or tiff files. 
Please send the files directly to me, the mailig list doesn't accept
large emails.

Cheers,
Rolf


Am 11.11.2014 um 18:32 schrieb Guillaume Courtois:
>
> 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.
>>>>>
>>>>>
>
>





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