[gentoo-user] libav/ffmpeg's bitrate options have no effect in Gentoo

[Casper Ti. Vector]

Recently I found that the `-b' and `-ab' options used for setting the
output bitrate in ffmpeg and libav have no effect on my Gentoo machine.
With Ubuntu (and the Medibuntu repository enabled), this does not
happen.

For example, for any `<bitrate>' I use in
    % ffmpeg -ab <bitrate> -i test.ape test.mp3
I get only `test.mp3' in 64kbps bitrate (as default setting). It's
similar as for other audio/video formats and/or the `-b' option.

My Gentoo system is updated daily with global ~amd64 keyword in use. I
recently switched from ffmpeg to libav and they are both affected by
this issue.

Is anybody facing the same issue? Has anyone got any idea about the
possible causes and/or solutions? Please tell me if more information is
needed, thanks.

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