[Ffmpeg-devel] [PATCH] audio channel extraction

[Axel Holzinger]

Hi

> Hi
>
> On Fri, Sep 15, 2006 at 02:21:13PM +0200, Baptiste Coudurier wrote:
> > Michael Niedermayer wrote:
> > > Hi
> > >
> > > On Fri, Sep 15, 2006 at 12:47:20PM +0200, Baptiste Coudurier wrote:
> > >> Hi
> > >>
> > >> This patch adds feature to extract specific channels from
> audio track.
> > >> My main goal was to split 4 channels tracks to 2 stereos tracks.
> > >
> > > what about a more generic system which could mix chanels together into
> > > other channels? so that there would be a AxB matrix of coefficients to
> > > mix A input channels into B output channels?
> > >
> > >
> > > [...]
> >
> > That would be a nice idea indeed, and would that be usefull for ac3/aac
> > downmixing also ?
>
> i think so
>
>
> > I might lack theory and good design skills to do that
> > though :/
> > Could you point me papers, or design ideas ?
>
> just leave the coefficients to the user as command line parameters

bad idea as the ac3 data already tells you how to downmix

or do you think the user shall read the ac3 data directly to find out how to
downmix?

Cheers
Axel