On Sun, Nov 30, 2014 at 01:15:43PM +0100, Vittorio Giovara wrote: > > On 30/11/2014 01:45, Christophe Gisquet wrote: > >Most of the code is actually not mine but originated from "Direct264": > >http://forum.doom9.org/showthread.php?t=152419 > >https://svn.code.sf.net/p/direct264/code/Patches/ > >Therefore I've tried to split as best as possible the code I have added. > >There are 3 controversial parts in this patch set: > >- the BSF API change (fixing it is out of my league/time budget) > >- the filter doing in-place filtering (?) > >- the level of validation for this new filter > > > >I've only tested the cropping feature, and validating that the rest > >works tenuous. Anyway, cropping is unfortunately not at all well > >supported: > >- VLC 2.1.5 (Windows) either crashes or outputs garbage > >- DXVA on some Intel core gets top/left cropping completely wrong > > (0,0 but something valid for bottom/right seems to be OK) > >- ffmpeg-based decoders (e.g. mplayer) are OK > > > >It is possible the implementation is incorrect but it was written > >following the specs. > > > I don't really understand this patchset nor the usecase for it.
I belive its usecase is to correct incorrect parameters in an SPS croping, aspect ratio level/profile, ... in cases where re-encoding with better parameters is not possible (broken encoder, source material unavailble, ... > While of course it's technically possible to change the SPS, it's a > VeryBadIdea to so. Especially if you are targetting cropping (which > is fixed in VLC 2.2 btw), you *never ever* have to ignore it, but > use it to crop the picture correctly, as it's a mandatory part in > the H264 specifications. If your use case is non-spec compliant, > then you already have a CODEC_FLAG for that, which does not modifies > the bitstream. > All other uses cases seem workaround for broken encoders/decoders, > it'd be better to fix those instead. > > Vittorio > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Concerning the gods, I have no means of knowing whether they exist or not or of what sort they may be, because of the obscurity of the subject, and the brevity of human life -- Protagoras
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