Hello, I've tried on a completely different computer (mine is an old Dell GX150 workstation with a PCI USB 2.0 controller, the other is a new Acer laptop) and I have exactly the same problem (with kernel 2.6.26).
However this time I could try on Windows Vista (which was on the laptop) and the webcam is working perfectly ! So now I really don't know where the problem is ? If both computers never have any problem with the USB controller and that the webcam is working on Vista and that I have other webcams using pwc driver which worked, it seems that the problem is in the uvcvideo module ? But some people on this mailing-list have reported that this webcam is working perfectly on linux ?!? I really don't know how to investigate further... I only have 3 days left for returning my webcam, so do you think that it's worth keeping the webcam and help debugging or should I return the webcam ? Thanks a lot anyway for the people who have tried to help ! It's very refreshing to have some kind of support... Regards, On Thu, 25 Jun 2009 13:44:13 +0200, Saint Germain <[email protected]> wrote : > Hello, > > 1) I will try this WE on a different computer which has USB 2.0 port > directly on motherboard and keep you update > 2) I've included all trace here : > http://forums.quickcamteam.net/showthread.php?tid=860 > 3) I have the problem with guvcview, luvcview, mplayer, kopete, > skype... So I don't think that is an application issue > > Thank you for your help ! > > 2009/6/25 Brian Pin <[email protected]>: > > Hi > > Maybe there are some possible reasons.. > > 1) dropping by the device because the host is too slow to drain the > > data, -> use a different host to test > > 2) dropping by the host uvc driver, -> turn on the trace to maximum > > to check if there is a drop > > 3) dropping by the application above uvc driver, -> probably be > > some timing issues or synchronization issues..don't know how to > > test, maybe a different application would tell the difference? > > > > Good luck > > > > > > 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 > >> _______________________________________________ > >> Linux-uvc-devel mailing list > >> [email protected] > >> https://lists.berlios.de/mailman/listinfo/linux-uvc-devel > > > > > > > > -- > > Best Regards > > Brian > > _______________________________________________ Linux-uvc-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
