On 18 May 2018 at 21:03, wm4 <nfx...@googlemail.com> wrote: > On Fri, 18 May 2018 20:09:02 +0100 > Rostislav Pehlivanov <atomnu...@gmail.com> wrote: > > > On 18 May 2018 at 20:05, 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: Tuesday, May 15, 2018 4:46:02 PM > > > > Subject: Re: [FFmpeg-devel] [PATCH v6 1/3] avcodec: add flags for > > > packets with top/bottom field > > > > > > > On 15 May 2018 at 18:03, wm4 <nfx...@googlemail.com> wrote: > > > > > > > >> On Tue, 15 May 2018 17:15:05 +0100 > > > >> Rostislav Pehlivanov <atomnu...@gmail.com> wrote: > > > >> > > > >> > On 15 May 2018 at 15:55, wm4 <nfx...@googlemail.com> wrote: > > > >> > > > > >> > > On Mon, 14 May 2018 18:26:35 -0400 > > > >> > > Patrick Keroulas <patrick.kerou...@savoirfairelinux.com> wrote: > > > >> > > > > > >> > > > Signed-off-by: Patrick Keroulas <patrick.keroulas@ > > > >> savoirfairelinux.com> > > > >> > > > --- > > > >> > > > doc/APIchanges | 3 +++ > > > >> > > > libavcodec/avcodec.h | 8 ++++++++ > > > >> > > > libavcodec/version.h | 4 ++-- > > > >> > > > 3 files changed, 13 insertions(+), 2 deletions(-) > > > >> > > > > > > >> > > > diff --git a/doc/APIchanges b/doc/APIchanges > > > >> > > > index bbefc83..d06868e 100644 > > > >> > > > --- a/doc/APIchanges > > > >> > > > +++ b/doc/APIchanges > > > >> > > > @@ -15,6 +15,9 @@ libavutil: 2017-10-21 > > > >> > > > > > > >> > > > API changes, most recent first: > > > >> > > > > > > >> > > > +2018-05-xx - xxxxxxxxxx - lavc 58.20.100 - avcodec.h > > > >> > > > + Add AV_PKT_FLAG_TOP_FIELD and AV_PKT_FLAG_BOTTOM_FIELD. > > > >> > > > + > > > >> > > > 2018-05-xx - xxxxxxxxxx - lavu 56.18.101 - hwcontext_cuda.h > > > >> > > > Add AVCUDADeviceContext.stream. > > > >> > > > > > > >> > > > diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h > > > >> > > > index fb0c6fa..14811be 100644 > > > >> > > > --- a/libavcodec/avcodec.h > > > >> > > > +++ b/libavcodec/avcodec.h > > > >> > > > @@ -1480,6 +1480,14 @@ typedef struct AVPacket { > > > >> > > > */ > > > >> > > > #define AV_PKT_FLAG_DISPOSABLE 0x0010 > > > >> > > > > > > >> > > > +/** > > > >> > > > + * The packet contains a top field. > > > >> > > > + */ > > > >> > > > +#define AV_PKT_FLAG_TOP_FIELD 0x0020 > > > >> > > > +/** > > > >> > > > + * The packet contains a bottom field. > > > >> > > > + */ > > > >> > > > +#define AV_PKT_FLAG_BOTTOM_FIELD 0x0040 > > > >> > > > > > > >> > > > enum AVSideDataParamChangeFlags { > > > >> > > > AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001, > > > >> > > > diff --git a/libavcodec/version.h b/libavcodec/version.h > > > >> > > > index 3fda743..b9752ce 100644 > > > >> > > > --- a/libavcodec/version.h > > > >> > > > +++ b/libavcodec/version.h > > > >> > > > @@ -28,8 +28,8 @@ > > > >> > > > #include "libavutil/version.h" > > > >> > > > > > > >> > > > #define LIBAVCODEC_VERSION_MAJOR 58 > > > >> > > > -#define LIBAVCODEC_VERSION_MINOR 19 > > > >> > > > -#define LIBAVCODEC_VERSION_MICRO 101 > > > >> > > > +#define LIBAVCODEC_VERSION_MINOR 20 > > > >> > > > +#define LIBAVCODEC_VERSION_MICRO 100 > > > >> > > > > > > >> > > > #define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_ > > > VERSION_MAJOR, > > > >> > > > >> > > \ > > > >> > > > > > > >> > > LIBAVCODEC_VERSION_MINOR, \ > > > >> > > > > > >> > > So far we could avoid codec-specific packet flags, and I think > it > > > >> > > should stay this way. Maybe make it side data, something with > naming > > > >> > > specific to the bitpacked codec. Or alternatively, if this codec > > > >> > > is 100% RTP specific and there's no such thing as standard > bitpacked > > > >> > > packets (e.g. muxed in other files etc.), add it to the packet > > > >> > > directly. The RTP code "repacks" it already on the libavformat > side > > > >> > > anyway. > > > >> > > _______________________________________________ > > > >> > > ffmpeg-devel mailing list > > > >> > > ffmpeg-devel@ffmpeg.org > > > >> > > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > > >> > > > > > >> > > > > >> > This codec isn't RTP specific, its the same as V210. There are > no > > > flags > > > >> in > > > >> > the bitstream, its just a sequence of packed pixels. And just > like > > > v210 > > > >> > there's a standard for what packets need to look like (rfc4175, > and > > > >> > unfortunately it does specify the fields need to be separate), > so > > > >> packing 2 > > > >> > fields in the muxer isn't really an option. > > > >> > > > >> Then why are there separate bitpacked and v210 decoders/codec_ids? > > > >> > > > > > > > > Its a different type of packing. > > > > > > > > > > > > > > > >> > Side data seems a bit of an overkill for a flag. I'd say the > field > > > flags > > > >> > are not codec specific as some raw codecs and containers can > signal > > > >> fields > > > >> > per packet. So I don't really mind them. > > > >> > > > >> You want codec specific flags to accumulate in AVPacket.flags? > Can't way > > > >> until we change the flags field to int128_t. > > > >> > > > >> > > > > No, but I think 2 more bits won't hurt much, especially considering > > > pretty > > > > much all formats supporting interlaced content split each field into > a > > > > separate packet. > > > > > > Recomposing a frame from fields on the demux side would make the > bitpacked > > > decoder > > > completely useless. Can we find a consensus? How about reusing > > > AVPictureStructure > > > as suggested by Derek? > > > > > > > _______________________________________________ > > > > 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 > > > > > > > Reusing that structure would mean adding a field to AVPackets. I'd rather > > avoid that, so I'm okay with the packet flags. > > We can't add fields to AVPacket (ABI issues). I'm against the flags > though. None of the current packet flags are needed for correct > decoding, why change that suddenly? > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel >
AV_PKT_FLAG_TRUSTED is needed to decode some packets, so it would not be an entirely new change. On the other hand, using side data would mean having to use AV_CODEC_CAP_PARAM_CHANGE, adding a AV_SIDE_DATA_PARAM_CHANGE_FIELD and adding a new AVCodecContext field to indicate the current field of a packet. Or adding a new 1-byte large side data type to indicate packet field. I think the packet flag solution is much saner than that. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel