Hello,

Do you have the Quickcam Pro 9000 or the Vision Pro ?
I didn't have any difficulty turning off the auto-exposure with both of them.
Have you tried with normal user and root ?
Anyway my problem was not so with the framerate (which may be
dependant of the exposure) but on dropped frames (which has an effect
on framerate)

Regards,

2009/6/25 Andrey Nechypurenko <[email protected]>:
>
> Hi,
>
>> 1) dropping by the device because the host is too slow to drain the data, -> 
>> use a different host to test
>
> I also have this camera and on my Dell Precission M6400 notebook running 
> latest stable Debian (lenny) luvcview shows no more then 10-12 fps so far.
> I did try it only in room with "normal" light conditions and auto-exposure 
> turned on. I beleave auto-exposure was turned on because as I know it is the 
> default setting and attempt to turn it off using luvcview does not work. I am 
> currently on different computer and do not remember exact error message but 
> it was just saying that attempt to turn it off failed.
>
> Just want to mention it to exclude USB and host performance related issue.
>
> Regards,
> Andrey.
>
>
> On Wed, Jun 24, 2009 at 5:29 PM, Saint Germain <[email protected]> wrote:
>
> I've tried disconnecting all PCI cards except the USB controler and
> using it in different slot, but same results.
> I also tried booting with acpi=off but no such luck.
>
> I will try on another computer this week end. Really strange... I never
> had any problem with this USB controler.
>
> I also have a Philips Toucam Pro (need pwc driver) which if connected
> on the same port works correctly without a single dropped frame (but
> with a poor definition, something about the previous pwcx module being
> reimplemented).
>
> Maybe some freak combination of motherboard + USB controler + UVC
> module ?
>
> I'll keep you updated this WE.
>
> Thanks for your help !
>
> On Wed, 24 Jun 2009 23:46:11 +0100, Paulo Assis <[email protected]>
> wrote :
>
>
>> The YUYV fps difference to MJPG, IMHO, can only be caused by the
>> frame size. MJPG is compressed so it can be some 10 times smaller
>> compared to YUYV. This also indicates that CPU is not a problem since
>> MJPG requires a lot more CPU (needs decompressing)
>> So if memory is also not a problem, the only thing left is the USB
>> connection.
>>
>> I'm just intrigued by the flickering, even at 20 fps video should be
>> acceptable, I'm guessing the driver is dropping some data, in yuv
>> case the entire frame as incomplete frames are droped by default, in
>> the case of MJPG since there is no way of knowing the complete frame
>> size (it varies due to the compression process), you just get part of
>> the frame and that causes the ficker.
>>
>> In any case all seems to point to the usb connection, so I would run
>> some tests on that.
>>
>> Best regards,
>> Paulo
>
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>
>
>
> --
> Best Regards
> Brian
>
>
>
>
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