[gstreamer-bugs] [Bug 556963] New: h264 playback choppy on most (but not all) files

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | don't know | Ver: 0.10.18
           Summary: h264 playback choppy on most (but not all) files
           Product: GStreamer
           Version: 0.10.18
          Platform: Other
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: major
          Priority: Normal
         Component: don't know
        AssignedTo: gstreamer-bugs at lists.sourceforge.net
        ReportedBy: bugs at mathrick.org
         QAContact: gstreamer-bugs at lists.sourceforge.net
     GNOME version: Unspecified
   GNOME milestone: Unspecified


Playback is consistently choppy for about 80% of h264 streams. The exact
symptoms is that it plays a couple of frames, then pauses for 100-200ms or
thereabouts, then plays a couple of frames again. Sound playback is unaffected,
and both CPU cores on my machine are keeping cool (<35%, including a stray
flash process somewhere in the browser, eating up about 20%). Some h264
streams, however, play just fine, again with absolutely no CPU trouble. Mplayer
plays all of the files fine.

Below I include two samples, a jerky one and a smooth one, as video-only
matroska files, cut down to 1MB. Also attached are logs from the playback. One
interesting thing I noticed from the logs is this:

mathrick at hatsumi:/tmp$ cat jerky.log | grep "default
gsttypefindhelper.c:93:helper_find_peek" | wc -l
80985
mathrick at hatsumi:/tmp$ cat smooth.log | grep "default
gsttypefindhelper.c:93:helper_find_peek" | wc -l
4754

For some reason, the majority of _playback_ time in the jerky sample is spent
calling helper_find_peek; this continues and doesn't stop until the pipeline is
finally disassembled by EOS.

Filing under "don't know" initially, since I honestly don't know which
component is to blame.


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