[FFmpeg-devel] [PATCH]lavf/mxfdec: Limit score for strangely cut files

[Carl Eugen Hoyos]

Am Di., 25. Aug. 2020 um 00:48 Uhr schrieb Tomas Härdin <tjoppen at acc.umu.se>:
>
> mån 2020-08-24 klockan 21:42 +0200 skrev Carl Eugen Hoyos:
> > Hi!
> >
> > Attached patch fixes ticket #8846, the sample there is both a mov and
> > an mxf file.
> > It is not entirely clear to me if the sample was only made to annoy us
> > but the content looks real.
> >
> > An alternative may be to check the extension if the score is equal but
> > I don't really like that either.
>
> The file is a polyglot, yes. The run-in feature in MXF exists to be
> able to add extra metadata and other MXF features while maintaining
> backward compatibility. And to be annoying.

The file does not play here with -f mxf...

> > Subject: [PATCH] lavf/mxfdec: Limit score for strangely cut files.
>
> I'd reword this to "lavf/mxfdec: Limit score for files with run-in"
>
> > @@ -3615,7 +3615,7 @@ static int mxf_probe(const AVProbeData *p) {
> >                  AV_RN32(bufp+ 4) == AV_RN32(mxf_header_partition_pack_key+ 4) &&
> >                  AV_RN32(bufp+ 8) == AV_RN32(mxf_header_partition_pack_key+ 8) &&
> >                  AV_RN16(bufp+12) == AV_RN16(mxf_header_partition_pack_key+12))
> > -                return AVPROBE_SCORE_MAX;
> > +                return bufp - p->buf ? AVPROBE_SCORE_MAX - 1 : AVPROBE_SCORE_MAX;
>
> bufp != p->buf would be more readable. Else this does the same thing as
> a patch I was just working on, so the logic is OK.

Patch applied.

Thank you, Carl Eugen