[FFmpeg-devel] [PATCH]Sanitize VBR setting for libfdk-aac

Derek Buitenhuis derek.buitenhuis at gmail.com
Wed Sep 12 20:56:32 CEST 2012

On 12/09/2012 2:03 PM, Reimar Döffinger wrote:
> Are you by chance not aware of this line of code?
> ffmpeg_opt.c:        st->codec->global_quality = FF_QP2LAMBDA * qscale;
> Note that lots of encoders like the vorbis, libspeex, ... one do exactly that same division.

It is not meant to be set with -qscale N.

It is meant to be set with -flags +qscale -global_quality N. This passes it through untouched,
and never introduces this FF_QP2LAMBDA nonsense. There's no need to cargo cult this FF_QP2LAMBDA
business. This approach is simpler.

- Derek

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