AAC encoder breaking 5.1 LFE channel
|Reported by:||elsiko||Owned by:|
|Blocking:||Reproduced by developer:||no|
|Analyzed by developer:||no|
Summary of the bug:
For a long time now, I've been doing some encodings into x265/aac using ffmpeg.
Recently I started noticing a problem with the audio channels that get - I think - mixed up.
The original file media info would show:
Front: L C R, Side: L R, LFE
But the encoded file will show:
Front: L C R, Side: C, Back: L R
I'm no expert, but I think the LFE channel is either dropped or converted.
I think this behaviour started around December 2017.
To be certain that something indeed changed, I encoded a file twice, used two static builds (from here: https://johnvansickle.com/ffmpeg/), once using a build from 2017-09-02, and one from 2018-01-24.
I attached to the tickets the logs of both encodings, the media info (+ the original).
You can download the original mkv file, as well as encoded files from there: http://18.104.22.168/encoding-results/
You can clearly see in the mediainfo of 2017 that the channels were correct (with LFE), but that's not the case in the 2018 encoding.
One last thing, I think this problem might be related to this ticket: https://trac.ffmpeg.org/ticket/6965
Change History (9)
comment:1 by , 4 years ago
|Summary:||AAC encoder breaking 5.1 channels → AAC encoder breaking 5.1 LFE channel|