Hi Alexey, Agreed, but bear in mind this patch I submitted is not for inclusion and merge in the git tree, it is just for testing purpose, it will never be merged in the git.
This is just a one shot patch to show some informations and then you can throw it away once you have the informations. But yes I could make it use the uvc_trace() API, it won't kill me :) Thanks for your feed back on the patch, do you have the time to test it on your webcams and to publish part of your syslog ? Regards, Yann Le 12/06/11 08:24, Alexey Fisher a écrit : > Hi, > > please use "uvc_trace(UVC_TRACE_DESCR," or pr_debug instead of printk. > So you can enable verbosity only if you need. > > On Di, 2011-06-07 at 17:56 +0200, Yann Sionneau wrote: >> Hi again, >> >> here is as attached file a new patch that applies to linux 2.6.39 tree >> (linux-2.6.git, tag v2.6.39). >> >> This patch now prints at the end of each stream : >> >> (*) total number of PTS (taking into account each packet) >> (*) total number of SCR >> (*) total number of ERR >> (*) number of packets without PTS (nb_missing_pts) >> (*) number of packets without SCR (nb_missing_scr) >> >> It will print as well for each packet (beware, it will hugely flood your >> syslog) : >> >> (*) SCR >> (*) diff with previous packet's SCR >> (*) PTS >> (*) diff with previous packet's PTS >> >> Beware, to see the "end of stream" statistics, you have to scroll up a >> little bit, it will be somewhere in the end of the per-packet >> information flood. >> >> Some results inline in the e-mail. >> >> On 06/06/2011 11:22 PM, Yann Sionneau wrote: >>> Le 06/06/11 19:42, Laurent Pinchart a écrit : >>>> Hi Yann, >>>> >>>> Thanks for the patch. >>>> >>>> On Friday 03 June 2011 15:48:59 Yann Sionneau wrote: >>>>> Hi Laurent and the UVC list, >>>>> >>>>> Here is a patch [snip] >>>> You should take all UVC packets into account, not just the first one for >>>> each >>>> frame. >>> Yes I don't know why in my head I thought only the first uvc packet >>> would have a header for the frame with timestamps and such, but it makes >>> no sense, each packet has its own header and the start of frame is just >>> signaled by the toggling of the FID :) >>> >>>> the important information are >>>> >>>> - do all frames have a PTS timestamp in their first packet ? >>> It seems so yes, at least on the two webcams I tried with the patch. >>> >>>> - do all non-empty packets for a frame have a PTS timestamp, and is it >>>> constant through the whole frame as it should be ? >>> Let's modify the patch to count the PTS and SCR of all packets instead >>> of only one per frame in order to sort this out ! >> I tested with the Logitech HD Pro C910, all packets have a PTS. >> PTS are indeed constant through the whole frame as it should be. >>>> - how many SCR timestamps do we have per frame ? are they constant through >>>> the >>>> whole frame or do they vary as they should ? >>>> >>> Same here ! >> With the same webcam, all packets have a SCR. >> The SCR value does vary through each frame, as it should do. >> The difference between the previous SCR is usually the same, except at a >> regular interval where there is a "jump" in SCR values. >> >> for example, SCR - SCR_prev would be 7 times the same difference, and >> then it will change for just one time, and then go back to the old >> difference for 7 times etc. >> >>>>> [snip] >>> Thanks for your review and comments, will submit a new patch ASAP ! > _______________________________________________ Linux-uvc-devel mailing list Linux-uvc-devel@lists.berlios.de https://lists.berlios.de/mailman/listinfo/linux-uvc-devel
