[Ffmpeg-devel] -ab 128 doesn't work with aac encoding?

Colin McKellar blibbler
Fri Aug 26 02:07:21 CEST 2005

On 25/08/05, Patrice Bensoussan <patrice.bensoussan at free.fr> wrote:
> Hello,
> I'm trying to convert a WMA file to AAC 128kbit, but it seems the -ab
> option
> doesn't work : when I use -ab 128, the created file is 94kbit
> according to quicktime 7 :
> Any idea what is happening? (i'm using the lastest ffmpeg cvs)

AAC has no CBR method, at best, it is ABR. If the file does not have
the complexity to require 128kbps, then it will be below the requested
bitrate. I suspect that if you had a longer sample, it would more
likely reach the bitrate.

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