[FFmpeg-devel] [PATCH 0/2] libvpxenc: Fix CQ encoding without a specified bitrate

James Zern jzern at google.com
Fri Aug 17 20:10:42 CEST 2012

On Fri, Aug 17, 2012 at 8:55 AM, Michael Niedermayer <michaelni at gmx.at> wrote:
> This patchset attempts to do something sane and expected in case no bitrate
> is set. Actually i had expected that simply leaving bitrate at 0 would cause
> encoding to use the CQ value, but testing shows it doesnt, so this now
> forces a huge bitrate which leads to quality based encoding in the absence
> of a specified bitrate.

Yes unfortunately the two are tied together. The lib uses the bitrate
as a max in cq mode and if it can't achieve the quality below that
bitrate it falls back to vbr mode.

> Also if neither a quality nor a bitrate is specified a warning is printed
> and whatever was in the bitrate field of libvpx is then used.
> Michael

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