On 26.10.2016 20:15, Paul B Mahol wrote: > On 10/25/16, Michael Niedermayer <mich...@niedermayer.cc> wrote: >> On Tue, Oct 25, 2016 at 07:45:25PM +0200, Andreas Cadhalpun wrote: >>> On 25.10.2016 12:58, Paul B Mahol wrote: >>>> patch(es)have good intent, but better fix is doing/checking it in single >>>> place. >>> >>> I don't agree. >>> In general, validity checks should be where the values are actually read. >>> This eliminates the risk that bogus values could cause problems between >>> being set >>> and being checked. >>> Also, having only a check in a central place is bad for debugging, because >>> it is >>> not immediately clear where the bogus value came from, when the check is >>> triggered. >>> (I know this from personal experience debugging all the cases triggering >>> the >>> assert in av_rescale_rnd.) >>> >>> The problem with that approach is that such checks can easily be >>> forgotten, which >>> is why I think a check in a central place would make sense in addition to >>> checking >>> the individual cases. >> >> some formats may also lack a sample rate like mpeg ps/ts >> the fact is known insude the demuxer, generic code after it doesnt >> know. Doing the only check after the parser is a bit late OTOH >> >> [...] >> >> -- >> Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB >> >> What does censorship reveal? It reveals fear. -- Julian Assange >> > > I'm not (yet) aware of better "fix" so do as you like.
Have you seen the patch for checking this in a central place [1]? It would catch all the negative sample rates, but not the negative timescales. (I still think it should be checked both centrally and locally.) Best regards, Andreas 1: https://ffmpeg.org/pipermail/ffmpeg-devel/2016-October/201769.html _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel