[FFmpeg-trac] #4078(ffmpeg:new): Specify audio bitrate per-channel

FFmpeg trac at avcodec.org
Tue Nov 4 11:55:16 CET 2014

#4078: Specify audio bitrate per-channel
             Reporter:  Haravikk  |                     Type:  enhancement
               Status:  new       |                 Priority:  normal
            Component:  ffmpeg    |                  Version:  unspecified
             Keywords:            |               Blocked By:
             Blocking:            |  Reproduced by developer:  0
Analyzed by developer:  0         |
 Fairly self-explanatory, but currently we can specify audio bit-rate for
 the entire stream, but this requires us to calculate the total bitrate
 from the number of input channels ourselves.

 This is fine for single files, but for batch-encoding a mixture of stereo
 and surround-sound content it's not as ideal, or even for encoding a file
 that contains multiple audio-streams.

 To accommodate these use-cases I'd like to request an alternative syntax
 for specifying audio channels with a per-channel bit-rate so that I can
 instead just specify say 64k per channel for AAC, with ffmpeg
 automatically using a total of 128k for stereo or 384k for 5.1 etc.

 I'm not sure what the best way to do this would be. I suppose one option
 would be to have a new parameter -bc for "bits per channel", so I could
 specify something like ffmpeg -i "$INFILE" -acodec aac -bc:a 64k

 An alternative would be allowing some kind of suffix to the -b option such
 as: ffmpeg -i "$INFILE" -acodec aac -b:a 64k/c "$OUTFILE"

Ticket URL: <https://trac.ffmpeg.org/ticket/4078>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker

More information about the FFmpeg-trac mailing list