Hi Grazvydas, On Tue, Nov 04, 2014 at 01:16:03AM +0200, Grazvydas Ignotas wrote: > Hi, > > On Mon, Nov 3, 2014 at 12:57 AM, Sakari Ailus <sakari.ailus@xxxxxx> wrote: > > Hi Grazvydas, > > > > On Sun, Nov 02, 2014 at 04:03:55AM +0200, Grazvydas Ignotas wrote: > >> There is periodic stutter (seen in vlc, for example) since 3.9 where > >> the stream stops for around half a second every 3-5 seconds or so. > >> Bisecting points to 1b18e7a0be859911b22138ce27258687efc528b8 "v4l: > >> Tell user space we're using monotonic timestamps". I've verified the > >> problem is there on stock Ubuntu 14.04 kernel, 3.16.7 from kernel.org > >> and when using media_build.git . The commit does not revert on newer > >> kernels as that code changed, but checking out a commit before the one > >> mentioned gives properly working kernel. > >> > >> I'm using Logitech C920 which can do h264 compression and playing the > >> video using vlc: > >> cvlc v4l2:///dev/video0:chroma=h264:width=1280:height=720 > > > > I've got Logitech C270 here but I can't reproduce the problem. The frame > > rate with the above command is really low, around 5. With a smaller > > resolution it works quite smoothly. The reason might be that the pixel > > format is still YUYV. The other option appears to be MJPG. > > I've tried lower resolution and YUYV with MJPG too, this has the same problem: > cvlc v4l2:///dev/video0:chroma=h264:width=320:height=240 > cvlc v4l2:///dev/video0:chroma=yuyv:width=320:height=240 > > > > > My vlc is of version 2.0.3 (Debian). Which one do you have, and does it use > > libv4l2? > > Mine is 2.1.4, my distro is Ubuntu 14.04. I can see libv4l2.so.0.0.0 > in maps, but I have no idea what it's used for.. > > > Have you tried with a different application to see if the problem persists? > > Tried mplayer and cheese now, and it seems they are not affected, so > it's an issue with vlc. I wonder why it doesn't like newer flags.. > > Ohwell, sorry for the noise. I guess the newer VLC could indeed pay attention to the monotonic timestamp flag. Remi, any idea? -- Cheers, Sakari Ailus e-mail: sakari.ailus@xxxxxx XMPP: sailus@xxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
