----- Original Message ----- > From: "wm4" <nfx...@googlemail.com> > To: ffmpeg-devel@ffmpeg.org > Sent: Wednesday, May 23, 2018 12:02:45 PM > Subject: Re: [FFmpeg-devel] [PATCH v6 1/3] avcodec: add flags for packets > with top/bottom field
> On Wed, 23 May 2018 16:46:17 +0100 > Rostislav Pehlivanov <atomnu...@gmail.com> wrote: > >> On 23 May 2018 at 16:18, wm4 <nfx...@googlemail.com> wrote: >> >> > On Tue, 22 May 2018 17:19:35 -0400 (EDT) >> > Patrick Keroulas <patrick.kerou...@savoirfairelinux.com> wrote: >> > >> > > ----- Original Message ----- >> > > > From: "Rostislav Pehlivanov" <atomnu...@gmail.com> >> > > > To: "FFmpeg development discussions and patches" < >> > ffmpeg-devel@ffmpeg.org> >> > > > Sent: Friday, May 18, 2018 5:28:42 PM >> > > > Subject: Re: [FFmpeg-devel] [PATCH v6 1/3] avcodec: add flags for >> > packets with top/bottom field >> > > >> > > > On 18 May 2018 at 22:17, wm4 <nfx...@googlemail.com> wrote: >> > > >> > > >> > > >> > > > > But I think a new side data type would be much saner. We could even >> > > > > just make it something generic, like AV_PKT_DATA_ANCILLARY or >> > > > > something. It's apparently just packet data which somehow couldn't go >> > > > > into the packet data. >> > > >> > > >> > > > I agree, a generic ancillary side data type sounds better. It would >> > have to >> > > > be handled the same way as mastering metadata (e.g. to allocate it >> > you'd >> > > > need to use a separate function), since the size of the data struct >> > can't >> > > > be part of the API if we intend to add fields later. >> > > > Patrick, if you're okay with that you should submit a patch which bases >> > > > such side data on libavutil/mastering_display_metadata.h/.c >> > > >> > > No problem for transmitting field flags through side data. But the given >> > > example (libavutil/mastering_display_metadata.h/.c) attaches data to >> > > AVFrame, not AVPacket, so I'm not sure where to place this separate >> > > allocator function. Do you recommend to create a new >> > > libavcodec/ancillary.c/h utility? >> > >> > The example you mentioned exists for AVPacket too (it's just not easy >> > to see how it can end up in AVPacket, because no demuxer does that >> > directly). >> > >> > Anyway, ancillary side data would just be an untyped byte array, so I >> > don't think it needs any helpers. Just an addition to the packet side >> > data enum (I think it's somewhere in avcodec.h). >> > _______________________________________________ >> > ffmpeg-devel mailing list >> > ffmpeg-devel@ffmpeg.org >> > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel >> > >> >> I'd rather have it as a well defined typed array rather than a bunch of >> bytes. Otherwise we'd start sending unknown side data info and users >> wouldn't know what to do with it. > > Unless you're adding some meta object system for describing arbitrary > types at runtime I don't know how you'd do that. Is that ok if I simply define a basic struct to hold the field? Any suggestion on where to insert the definition of this data and the accessors in lavc? In a new source file? > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
