[FFmpeg-devel] [PATCH 1/3] mpeg12dec: validate color space

[Ronald S. Bultje]

Hi,

On Wed, Jan 25, 2017 at 8:20 PM, Andreas Cadhalpun <
andreas.cadhalpun at googlemail.com> wrote:

> On 07.01.2017 13:44, Ronald S. Bultje wrote:
> > On Fri, Jan 6, 2017 at 9:35 PM, Michael Niedermayer
> <michael at niedermayer.cc>
> > wrote:
> >
> >> On Fri, Jan 06, 2017 at 09:43:24PM +0100, Andreas Cadhalpun wrote:
> >>> On 23.12.2016 00:57, Andreas Cadhalpun wrote:
> >>>> Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
> >>>> ---
> >>>>  libavcodec/mpeg12dec.c | 4 ++++
> >>>>  1 file changed, 4 insertions(+)
> >>>>
> >>>> diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
> >>>> index 63979079c8..d3dc67ad6a 100644
> >>>> --- a/libavcodec/mpeg12dec.c
> >>>> +++ b/libavcodec/mpeg12dec.c
> >>>> @@ -1470,6 +1470,10 @@ static void mpeg_decode_sequence_display_
> extension(Mpeg1Context
> >> *s1)
> >>>>          s->avctx->color_primaries = get_bits(&s->gb, 8);
> >>>>          s->avctx->color_trc       = get_bits(&s->gb, 8);
> >>>>          s->avctx->colorspace      = get_bits(&s->gb, 8);
> >>>> +        if (!av_color_space_name(s->avctx->colorspace)) {
> >>>> +            av_log(s->avctx, AV_LOG_WARNING, "Invalid color space %d,
> >> setting to unspecified\n", s->avctx->colorspace);
> >>>> +            s->avctx->colorspace = AVCOL_SPC_UNSPECIFIED;
> >>>> +        }
> >>>>      }
> >>>>      w = get_bits(&s->gb, 14);
> >>>>      skip_bits(&s->gb, 1); // marker
> >>>>
> >>>
> >>> Ping for the series.
> >>
> >> i have no real objection to it.
> >> iam used to see these being exported unchanged though so it feels a
> >> bit odd
> >
> >
> > Doesn't this destroy exporting of newly added colorspaces that have no
> > explicit mention yet in libavutil? I'm not 100% sure this is a good
> thing.
>
> Yes. That's how it is already done in libavcodec/h264_ps.c, so it just
> makes handling unknown values consistent.


Changing h264_ps.c would also make things consistent.

The question is not whether changing A or B towards the other makes the
combination consistent. The question is which form of consistency is
better...

Ronald