Small delays and framerate deviations on video playback

[4ernov]

Hello,

I have a video application based on GStreamer-0.10. Suddenly I found
strange framerate deviations and microdelays in the video stream that
is displayed. These effects are especially noticeable on still videos
and slow camera motion which looks like stop and starts. It's not any
major display problem as these artifacts are indeed minor, it's more
like small mistakes with frame showtime.

My application is multiplatform and the problem mentioned above is
reproducible on Windows, Mac OS X and Linux which means that it's not
an issue with concrete output sink. I logged some detailes logs from
xvimagesink, but jitter and interframe periods are quite good: jitter
is always negative and is around -25 ms (from -6 to -40 ms) and
display times go monotonic in 40 ms (which is right for my 25 fps).
What's more, I also tried gst-launch 0.10 and 1.0 as well as several
different players (ffplay, VLC) with several container and video
formats (raw H.264, MP4/H.264, OGG/Theora, Webm/VP8) but the results
are pretty much the same: there's deviations on video. The only test
case that I finished successfully is omxplayer on Raspberry Pi, it's
output video stream looks very smooth without any displaying problems.

It seems that there could be some serious problem concerning video
output. Did anyone suffer a problem like this? Maybe, there're known
issues or workarounds with that? I pretty much sure that it could be
either clocking problem in basesink or rendering problem in other
sinks, but I have no arguments on that.

Thanks in advance!

Alexey Chernov