[FFmpeg-devel] [PATCH v1 2/2] avcodec/mpeg12enc: Support mpeg2 encoder profile with const options

[Fu, Linjie]

> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> Limin Wang
> Sent: Friday, April 3, 2020 22:55
> To: ffmpeg-devel at ffmpeg.org
> Subject: Re: [FFmpeg-devel] [PATCH v1 2/2] avcodec/mpeg12enc: Support
> mpeg2 encoder profile with const options
> 
> On Fri, Apr 03, 2020 at 04:25:15PM +0200, Hendrik Leppkes wrote:
> > On Fri, Apr 3, 2020 at 3:12 PM <lance.lmwang at gmail.com> wrote:
> > >
> > > From: Limin Wang <lance.lmwang at gmail.com>
> > >
> > > make setting profile more user friendly
> > >
> >
> > Please make sure API users can still set it through avctx->profile,
> > otherwise this would be an API break.
> 
> Right, I'll update the patch to check avctx->profile != unknown, then
> overwrite
> the s->profile with it to void API break.
> 
Would it be better to determine the profile with a priority like:
1.s->profile; then
2. avctx->profile; then
3. a default profile;
in case both avctx->profile and s->profile are set?

If user set a profile explicitly (through either option in cmdline or av_opt_set()), 
above priority seems to be natural. (and libx264 [1] has the same logic)

- Linjie

[1] https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/libx264.c#L806