Opened 10 years ago

Closed 10 years ago

Last modified 10 years ago

#8652 closed defect (fixed)

Some h.264 encoded mkv files display audio sync issues

Reported by: John <jlagrone@…> Owned by: Janne Grunau
Priority: minor Milestone: unknown
Component: MythTV - Video Playback Version: Unspecified
Severity: medium Keywords:
Cc: Ticket locked: no


I have several dvd rips encoded with handbrake in h.264 in mkv containers with display severe audio sync issues. Namely the video plays faster than the audio in an accelerating manner, so setting an offset for the audio is not effective as it will soon be out of sync again.

I'm not entirely sure this is a myth issue or a handbrake issue (or something else I'm overlooking) as my older encodes seem fine and only the more recent ones seem to have this problem but the same files play fine vlc, xine, mplayer, and at least one old version of mythtv (r24587).

This problem manifests itself in r25331. I have tried using different playback profiles and audio options and seen no change. I've attached mythfrontend log with -v genereal,important,playback,audio

Attachments (1)

mythfrontend.log (298.2 KB) - added by John <jlagrone@…> 10 years ago.
mythfrontend log

Download all attachments as: .zip

Change History (5)

Changed 10 years ago by John <jlagrone@…>

Attachment: mythfrontend.log added

mythfrontend log

comment:1 Changed 10 years ago by tralph

Please try r25285 and report back. Also a sample would be appreciated.

I do notice that your video has mixed interlaced/progressive frames according to the logs but I'm unaware that this has ever caused an sync issue.

comment:2 Changed 10 years ago by John <jlagrone@…>

r25285 works. r25286 does not. I put a clip that's about 1 minute / 13.5 MB here that exhibits the problem.

comment:3 Changed 10 years ago by tralph

Resolution: fixed
Status: newclosed

fixed in r25352.

comment:4 Changed 10 years ago by tralph

John, I fixed the problem where we make adjustments when the video timecodes don't match the frame intervals. This allows your video to playback much better. However, you may or may not notice but some video jitter is going to occur. Whatever software you are using is setting the container fps to 60000/1001. It appears you took a 29.97 fps DVD and detelecined to 23.976 so your container frame rate should have been set to 24000/1001. You can easily remux your video and specify the proper fps using mkvtoolnix-gui programs.

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