[FFmpeg-devel] [PATCH 000/279] New channel layout API

[Anton Khirnov]

Quoting Nicolas George (2021-12-08 11:55:40)
> James Almer (12021-12-07):
> > This is an updated and rebased version of the API that was sent to this mailing
> > list about two years ago. It expands it with some new helpers, implements some
> > changes that allows further extensibility for new features down the line, and
> > finishes porting all missing modules and those introduced since 2019.
> 
> I see the concerns I raised last time have not been addressed:
> 
> (1) the ability to have a channel at a certain location several times;

I have no idea what you mean, the CUSTOM order can have any channel at
any location. This was true in all versions of this API back to 2013.

> 
> (2) the ability to attach an arbitrary label to a channel or to a group
>     of channels;
> 
> (3) an API and syntax for the user to specify a particular channel.
> 
> (1) is necessary for the amerge filter: merge two stereo streams, you
> get two FL and two FR.
> 
> (1) is also necessary for devices that can record several sources
> simultaneously. IIRC, that is the case for the BlackMagick devices. If
> your devices records a band from two stereo and three mono microphones,
> we need two FL, two FR and three FC.

Multiplexing multiple streams into a single AVFrame is not a valid use
case. Just use multiple streams.

-- 
Anton Khirnov