[FFmpeg-devel] [PATCH v2 2/8] avformat/mov: check that pcmC box is of the expected type

[Jan Ekström]

On Mon, Feb 27, 2023 at 3:36 PM Tomas Härdin <git at haerdin.se> wrote:
>
> lör 2023-02-25 klockan 02:28 +0800 skrev Zhao Zhili:
> > From: Jan Ekström <jeebjp at gmail.com>
> >
> > As per 23003-5:2020 this box is defined as
> > PCMConfig extends FullBox(‘pcmC’, version = 0, 0), which means
> > that version is 0 and flags should be zero.
> > ---
> >  libavformat/mov.c | 13 +++++++++++--
> >  1 file changed, 11 insertions(+), 2 deletions(-)
>
> Probably OK, but I'm not versed i the version problems relating to this
> tag. Should we also support version > 0?
>
> /Tomas

pcmC only has version 0 and flags coded to zero, thankfully

The channel layout box is where the "fun" begins with version 1 as
well as this following quote:

> When authoring, version 1 should be preferred over version 0.
> Version 1 conveys the channel ordering, which is not always the case for
> version 0. Version 1 should be used to convey the base channel count for DRC.

Jan