On Thu, 1 Aug 2024 at 00:58, Anton Khirnov <an...@khirnov.net> wrote: >
Thanks for the review. > Quoting Josh Allmann (2024-07-09 21:05:47) > > Encoders may emit a buffering period SEI without a corresponding > > SPS/PPS if the SPS/PPS is carried out-of-band, eg with avcc. > > > > During Annex B conversion, this may result in the SPS/PPS being > > inserted *after* the buffering period SEI but before the IDR NAL. > > > > Since the buffering period SEI references the SPS, the SPS/PPS > > needs to come first. > > --- > > > > Notes: > > v2: Updated FATE test refs > > > > libavcodec/bsf/h264_mp4toannexb.c | 13 +++++++++++++ > > tests/ref/fate/h264-bsf-mp4toannexb | 2 +- > > tests/ref/fate/h264_mp4toannexb_ticket2991 | 18 +++++++++--------- > > tests/ref/fate/segment-mp4-to-ts | 12 ++++++------ > > 4 files changed, 29 insertions(+), 16 deletions(-) > > > > diff --git a/libavcodec/bsf/h264_mp4toannexb.c > > b/libavcodec/bsf/h264_mp4toannexb.c > > index 92af6a6881..6607f1e91a 100644 > > --- a/libavcodec/bsf/h264_mp4toannexb.c > > +++ b/libavcodec/bsf/h264_mp4toannexb.c > > @@ -363,6 +363,19 @@ static int h264_mp4toannexb_filter(AVBSFContext *ctx, > > AVPacket *opkt) > > if (!new_idr && unit_type == H264_NAL_IDR_SLICE && (buf[1] & > > 0x80)) > > new_idr = 1; > > > > + /* If this is a buffering period SEI without a corresponding > > sps/pps > > + * then prepend any existing sps/pps before the SEI */ > > + if (unit_type == H264_NAL_SEI && buf[1] == 0 && !sps_seen && > > !pps_seen) { > > That 0 should be SEI_TYPE_BUFFERING_PERIOD, right? > Yes - fixed > > + if (s->sps_size) { > > + count_or_copy(&out, &out_size, s->sps, s->sps_size, > > PS_OUT_OF_BAND, j); > > + sps_seen = 1; > > + } > > + if (s->pps_size) { > > + count_or_copy(&out, &out_size, s->pps, s->pps_size, > > PS_OUT_OF_BAND, j); > > + pps_seen = 1; > > + } > > Is there a reason to insert the PPS? IIUC only the SPS is needed. > I believe it would be needed if using this bsf with the segment muxer, and segmentation happens on a recovery point (with a buffering period), eg in the test fate-segment-mp4-to-ts . Granted it is kind of incidental that this patch actually fixes that specific case. I have never seen a SPS without a PPS though. Josh _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".