[FFmpeg-devel] [PATCH 1/2] avformat/mux: Warn if the muxers bitexact flag is not set but it looks as if the user wants it set

[Ronald S. Bultje]

Hi,

On Sun, Aug 23, 2015 at 5:52 AM, Andreas Cadhalpun <
andreas.cadhalpun at googlemail.com> wrote:

> On 23.08.2015 11:09, Michael Niedermayer wrote:
> > From: Michael Niedermayer <michael at niedermayer.cc>
> >
> > Note: I doubt requiring this in the future is a good idea
> > See: [FFmpeg-devel] [PATCH 3/4] fate: add -fflags +bitexact to the
> relevant targets
> > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > ---
> >  libavformat/mux.c |    7 ++++++-
> >  1 file changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/libavformat/mux.c b/libavformat/mux.c
> > index 81c4676..77a24cc 100644
> > --- a/libavformat/mux.c
> > +++ b/libavformat/mux.c
> > @@ -250,10 +250,15 @@ static int init_muxer(AVFormatContext *s,
> AVDictionary **options)
> >          (ret = av_opt_set_dict2(s->priv_data, &tmp,
> AV_OPT_SEARCH_CHILDREN)) < 0)
> >          goto fail;
> >
> > +    if (s->nb_streams && s->streams[0]->codec->flags &
> AV_CODEC_FLAG_BITEXACT) {
> > +        if (!(s->flags & AVFMT_FLAG_BITEXACT))
> > +            av_log(s, AV_LOG_WARNING, "Muxer bitexact flag is not set,
> please set AVFormatContext.flags |= AVFMT_FLAG_BITEXACT.\n"
> > +                                      "This will become mandatory with
> future API cleanup\n"
> > +            );
>
> Such a warning is probably a good idea.
> However, either it should be removed together with FF_API_LAVF_BITEXACT
> (which only makes sense if we keep FF_API_LAVF_BITEXACT until next time)
> or the warning has to change, when FF_API_LAVF_BITEXACT is disabled.
> Saying 'future API cleanup', when the cleanup already happened seems wrong.


See FF_API_OLD_FILTER_OPTS_ERROR, is probably a good template.

I'm fine with this, but what do you think of a utility -bitexact option
that sets all bitexact flags? Most fate test commands can be halved if we
use that. But your choice.

Ronald