Opened 11 years ago

Closed 11 years ago

#5750 closed defect (fixed)

Unable to play most of my h264 videos since .21 release

Reported by: anonymous Owned by: Anduin Withers
Priority: minor Milestone: unknown
Component: mythvideo Version: unknown
Severity: medium Keywords:
Cc: Ticket locked: no

Description

I am unable to play most of my video collection using .21-fixes. I tried again today with r18457 hoping the recent ffmpeg sync (r18372) would make a difference. The last revision I was able to play these with was from November 8, 2007. The most obvious change after that point was the multi-channel audio merge.

Videos that don't play have accelerated sound and choppy video. Verbose output shows numerous " NVP::AddAudioData?():p1: Audio buffer overflow, audio data lost!" entries. The few videos that do play, do so without those messages.

My video collection is all ripped from DVD and encoded with mencoder using "-ovc x264 -x264encopts bitrate=1200:pass=2:deblock:cabac:threads=auto -vf hqdn3d=2:1:2 -oac copy". I do use 2 pass encoding.

I am attaching logs of a video with and without problems with "-v playback,audio,libav"

My last attempt to build mythtv used "./configure --enable-proc-opt --disable-ffmpeg-pthreads". Enabling or disabling ffmpeg-pthreads makes no difference. I am having this problem on three machines with different processors (Opteron 180, E8400 and an AppleTV).

Attachments (3)

bad_playback.txt (88.9 KB) - added by anonymous 11 years ago.
log of video that has the issue
good_playback.txt (23.1 KB) - added by anonymous 11 years ago.
log of video that does not have the issue
old_version.txt.gz (133.6 KB) - added by anonymous 11 years ago.
log of the video that fails when working on older checkout from 11.07.2007

Download all attachments as: .zip

Change History (6)

Changed 11 years ago by anonymous

Attachment: bad_playback.txt added

log of video that has the issue

Changed 11 years ago by anonymous

Attachment: good_playback.txt added

log of video that does not have the issue

Changed 11 years ago by anonymous

Attachment: old_version.txt.gz added

log of the video that fails when working on older checkout from 11.07.2007

comment:1 Changed 11 years ago by anonymous

When I looked at the logs from the two versions, I noticed the following:

Old pre-.21 revision: WriteAudio?: Preparing 6144 bytes (1536 frames) 2008-09-27 21:51:29.450 AO: audio waiting for space on soundcard: have 832 need 6144

.21 and later: NVP::AddAudioData?():p1: Audio buffer overflow, audio data lost!

From the logs, it appears the older version was able to buffer audio until the hardware could handle it whereas the newer code simply overflows and loses the data. Then again, without reading the code, I could be way off.

All three of my machines do use on-board audio with intel drivers (snd_intel8x0 and snd_hda_intel).

comment:2 Changed 11 years ago by anonymous

As an additional note, 5313-v2.patch (ticket 5313) appears to resolve this. It's also resolved in Trunk.

comment:3 Changed 11 years ago by Dibblah

Resolution: fixed
Status: newclosed

Reported as fixed in trunk

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