[FFmpeg-devel] [PATCH] Add a G.722 encoder

[Martin Storsjö]

On Fri, 10 Sep 2010, Martin Storsj? wrote:

> On Fri, 10 Sep 2010, Michael Niedermayer wrote:
> 
> > On Fri, Sep 10, 2010 at 04:24:00PM +0300, Martin Storsj? wrote:
> > > Hi,
> > > 
> > > As in $subj, the first patch adds a straightforward encoder that produces 
> > > bitexact output matching the reference test vectors. The second patch adds 
> > > trellis support to the encoder, closely modelled after the code in 
> > > libavcodec/adpcm.c.
> > > 
> > > I'm only doing trellis on the lower sub-band, since the higher only is 
> > > encoded with 2 bits. And if I'd want to do trellis for both of them at the 
> > > same time, I'd have to run the QMF on the output from both subbands in 
> > > order to get one decoded sample values, in order to have one difference 
> > > instead of two to compare.
> > 
> > why not comapare 2 ?
> > 
> > diff= (a0-a1)^2 + C*(b0-b1)^2
> 
> I guess that's doable, too, I'll try that.

This actually turned out to work quite well, thanks! New version attached 
that does trellis for both of them at the same time.

// Martin
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