[FFmpeg-devel] [PATCH] avcodec/mpeg4videodec: Add support for parsing and exporting video_range

[Michael Niedermayer]

On Sun, Dec 10, 2017 at 07:56:49PM +0000, Mark Thompson wrote:
> On 10/12/17 15:20, Michael Niedermayer wrote:
> > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > ---
> >  libavcodec/mpeg4video.h    |  3 +++
> >  libavcodec/mpeg4videodec.c | 32 ++++++++++++++++++++++++++++++++
> >  2 files changed, 35 insertions(+)
> > 
> > diff --git a/libavcodec/mpeg4video.h b/libavcodec/mpeg4video.h
> > index 515b008ae4..0ba502d50b 100644
> > --- a/libavcodec/mpeg4video.h
> > +++ b/libavcodec/mpeg4video.h
> > @@ -43,6 +43,9 @@
> >  #define ACE_VO_TYPE             12
> >  #define ADV_SIMPLE_VO_TYPE      17
> >  
> > +#define VOT_VIDEO_ID 1
> > +#define VOT_STILL_TEXTURE_ID 2
> > +
> >  // aspect_ratio_info
> >  #define EXTENDED_PAR 15
> >  
> > diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
> > index cdd7077f01..852f73f02c 100644
> > --- a/libavcodec/mpeg4videodec.c
> > +++ b/libavcodec/mpeg4videodec.c
> > @@ -1751,6 +1751,36 @@ static int mpeg4_decode_profile_level(MpegEncContext *s, GetBitContext *gb)
> >          s->avctx->level = 0;
> >      }
> >  
> > +    return 0;
> > +
> 
> Stray newline.
> 
> > +}
> > +
> > +static int mpeg4_decode_visual_object(MpegEncContext *s, GetBitContext *gb)
> > +{
> > +    int visual_object_type;
> > +    int is_visual_object_identifier = get_bits1(gb);
> > +
> > +    if (is_visual_object_identifier) {
> > +        skip_bits(gb, 4+3);
> > +    }
> > +    visual_object_type = get_bits(gb, 4);
> > +
> > +    if (visual_object_type == VOT_VIDEO_ID ||
> > +        visual_object_type == VOT_STILL_TEXTURE_ID) {
> > +        int video_signal_type = get_bits1(gb);
> > +        if (video_signal_type) {
> > +            int video_format = get_bits(gb, 3);
> > +            int video_range = get_bits1(gb);
> > +            int color_description = get_bits1(gb);
> > +
> > +            s->avctx->color_range = video_range ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
> > +
> > +            if (color_description) {
> > +                skip_bits(gb, 8+8+8);
> 
> Might be nice to extract the colour information as well?  (Should be able to set color_primaries/color_trc/colorspace directly, I think.)

will look into this
btw, iam a bit short on samples that use this
i had found just one sample after a quick look
more samples would be welcome, if someone has some.


[...]

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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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