Opened 5 years ago

Last modified 5 years ago

#2095 new defect

Regression with AC-3 audio after planar audio support was added

Reported by: subjunk@… Owned by: reimar
Priority: normal Component: core
Version: HEAD Severity: major
Keywords: Cc: cehoyos
Blocked By: Blocking:
Reproduced by developer: Analyzed by developer:

Description

This bug occurs with builds of MPlayer made after FFmpeg added planar audio support.

The following used to work, but now it doesn't:

mencoder input.mkv -oac lavc -of mpeg -ovc lavc -lavcopts vcodec=mpeg2video:acodec=ac3:abitrate=448 -o file.mpeg

If you remove the AC-3 parts it works:

mencoder input.mkv -oac lavc -of mpeg -ovc lavc -lavcopts vcodec=mpeg2video -o file.mpeg

I have uploaded a sample, but as far as I know it will work with any input; I have tested it with the following audio inputs: AC-3, AAC, FLAC.

Sample: http://www.spirton.com/uploads/MPlayer/Sample-AC3PlanarBug.mkv

Change History (4)

comment:1 Changed 5 years ago by subjunk@…

I forgot to say what the bug actually is ;)
Instead of outputting the audio, it outputs a buzzing sound.

comment:2 Changed 5 years ago by subjunk@…

Until this bug is fixed in MPlayer, I have temporarily fixed it by reverting the FFmpeg commit that caused it, which was b1540fc.

It should be noted (I said it on IRC but putting it here for a more permanent record) that FFmpeg is not affected by the bug - AC-3 encoding works in FFmpeg - so it does appear to be a bug with MPlayer's planar implementation rather than a bug in libav.

comment:3 Changed 5 years ago by cehoyos

  • Cc cehoyos@… added

Could you confirm that this problem is only reproducible with MEncoder, not with MPlayer? (It works fine here.)

comment:4 Changed 5 years ago by subjunk@…

Confirmed, I can't reproduce it with MPlayer, only MEncoder.
I couldn't see an option to use lavc with MPlayer but I tested with -ac a52 and -ac ffac3.

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