[FFmpeg-cvslog] r23460 - trunk/libavcodec/vorbis_enc.c

[Rafaël Carré]

On Fri,  4 Jun 2010 01:53:11 +0200 (CEST)
cehoyos <subversion at mplayerhq.hu> wrote:

> Author: cehoyos
> Date: Fri Jun  4 01:53:10 2010
> New Revision: 23460
> 
> Log:
> Raise default vorbis encoding quality.
> 
> Patch by Frank Barchard, fbarchard google com
> 
> Modified:
>    trunk/libavcodec/vorbis_enc.c


> -        venc->quality = 1.;
> +        venc->quality = 0.03;
>      venc->quality *= venc->quality;

This change make all encoded samples 0 (did you test libvorbis instead?)
Or in other words: completely silent output

To raise the quality this parameter should be higher,

-aq 30.0 gives around the same output size than oggenc for the one file
I tested and definitely better quality than before this commit.

Attached patch gives about the same results than using -aq 30.0.

Why does it use 3.0 and not 30.0 ?

I am not sure what the calculation involving CODEC_FLAG_QSCALE and
FF_QP2LAMBDA really means:
But I guess a "factor to convert from H.263 QP to lambda" (from
avcodec.h) isn't related to vorbis ?

-- 
Rafa?l Carr?
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