The VideoLAN Forums

Hi All,

I sent this email via the VLC dev email and I am posting the info here plus some additional observations in hope of someone else knowing a fix via config setting I hope.

Basically it looks as if VLC since some version of 1.1.x is stuttering or pausing for high definition video at least where youtube is concerned. It gets a little less of an issue if I set the http caching to 20 seconds yes I know that might be high but that in turn causes the delays before start to be quite when it does pause or stutter. I could not locate the GPU setting to try that and see if it helps.

I noticed if I pick an HD quality the video most of the time for youtube I get stutter and if I use the youtube video player on the page it runs just fine. I have not tried with other video viewers. Also, if I pick a youtube video that is not HD then it plays just fine. I also tried downloading the latest nightly 1.2 and get the same results.
Listed below is the enmail contents I sent to the dev team. Also, I am using Windows 7 32-bit and a 6 core AMD 1055T running around 2.8Ghz and a 13Mbps download bandwidth. My CPU activity is below 2% and using the Wireshark sniffer the bandwidth utilization is below 500Kbps.

Anyone have any advice? With everyone now viewing HD video seems like this would be extremely important issue to VLC. I am seeing more posting regarding issues similar to this if not identical. Most of them go back to 1.0.x or use a different viewer.

Here is what I sent. It shows the message box output during the stuttering and looks like the video buffer is being cleared quite often for some reason.

Thanks,
Tony

I noticed when playing youtube videos after awhile (10-90 seconds) I get a
constant stutter of the video (video starting/stopping). I am running under
Windows 7 32-bit.

The url for the video is:
http://www.youtube.com/watch?v=s7jJahUhQnY



The pattern I am seeing in the messages is the video buffer buffers then later
gets cleared then rebuffers.

maindebug: Buffering 91%
maindebug: Buffering 92%
maindebug: Buffering 94%
maindebug: Buffering 95%
maindebug: Buffering 96%
maindebug: Buffering 98%
maindebug: Buffering 99%
maindebug: Stream buffering done (1602 ms in 4351 ms)
maindebug: Decoder buffering done in 0 ms
mainwarning: PTS is out of range (13000), dropping buffer
mainwarning: output PTS is out of range (4540000), clearing out
mainwarning: PTS is out of range (-10000), dropping buffer
mainwarning: PTS is out of range (-33000), dropping buffer
mainerror: ES_OUT_SET_(GROUP_)PCR is called too late (pts_delay increased to
2749 ms)
maindebug: ES_OUT_RESET_PCR called
mainwarning: early picture skipped
maindebug: Buffering 0%
maindebug: Buffering 0%
maindebug: Buffering 1%
maindebug: Buffering 2%
maindebug: Buffering 3%
maindebug: Buffering 4%
maindebug: Buffering 5%
maindebug: Buffering 5%
maindebug: End of audio preroll
maindebug: Buffering 6%
maindebug: Buffering 7%

Regards,
-Tony

Okay I tried enabling GPU and it made no difference. I also tried HQ type videos and the same stutter occurs.

Regards,
-Tony

No, this is like the demuxer doesn't get the data in time... Very weird, indeed.

Hi JB,
Thanks for the prompt reply I know you are very busy.
FYI DVD's work great no problem.

Let me know if there are any settings you want me to try.

Regarding the demuxer is that why caching when set so large seems to help?

I am at a different part of the country. I will try to see if I run into the same issues and get back to this thread with the results.

-Tony

Same issue but seems to take longer before it starts to happen.
Thanks,
-Tony

Do you have libavformat module?