James Almer: > On 4/21/2024 12:32 PM, Andreas Rheinhardt wrote: >> James Almer: >>> If the demuxer doesn't set extradata in the stream's codecpar, a >>> need_context_update request will delete the previously extracted >>> extradata in >>> the stream's internal AVCodecContext. >>> As we can't ensure the old extradata is valid for the stream in its post >>> context update request state, try to get extradata from the new >>> packet instead >>> of attempting to preserve the old in some form. >>> >>> Signed-off-by: James Almer <jamr...@gmail.com> >>> --- >>> libavformat/demux.c | 12 +++++++++++- >>> 1 file changed, 11 insertions(+), 1 deletion(-) >>> >>> diff --git a/libavformat/demux.c b/libavformat/demux.c >>> index abfd5fee7d..39aa1cd4e3 100644 >>> --- a/libavformat/demux.c >>> +++ b/libavformat/demux.c >>> @@ -1319,6 +1319,8 @@ fail: >>> return ret; >>> } >>> +static int extract_extradata(FFFormatContext *si, AVStream *st, >>> const AVPacket *pkt); >>> + >>> static int read_frame_internal(AVFormatContext *s, AVPacket *pkt) >>> { >>> FFFormatContext *const si = ffformatcontext(s); >>> @@ -1373,6 +1375,11 @@ static int read_frame_internal(AVFormatContext >>> *s, AVPacket *pkt) >>> return ret; >>> } >>> + if (!sti->avctx->extradata && >>> + (ret = extract_extradata(si, st, pkt)) < 0) { >>> + av_packet_unref(pkt); >>> + return ret; >>> + } >>> sti->codec_desc = >>> avcodec_descriptor_get(sti->avctx->codec_id); >>> sti->need_context_update = 0; >>> @@ -2470,6 +2477,8 @@ static int extract_extradata(FFFormatContext >>> *si, AVStream *st, const AVPacket * >>> if (ret < 0) >>> return ret; >>> + av_bsf_flush(sti->extract_extradata.bsf); >>> + >>> ret = av_bsf_send_packet(sti->extract_extradata.bsf, pkt_ref); >>> if (ret < 0) { >>> av_packet_unref(pkt_ref); >>> @@ -3090,7 +3099,8 @@ find_stream_info_err: >>> err = codec_close(sti); >>> if (err < 0 && ret >= 0) >>> ret = err; >>> - av_bsf_free(&sti->extract_extradata.bsf); >>> + if (sti->extract_extradata.bsf) >>> + av_bsf_flush(sti->extract_extradata.bsf); >>> } >>> if (ic->pb) { >>> FFIOContext *const ctx = ffiocontext(ic->pb); >> >> This will keep the BSF around for longer than necessary, although only a >> tiny minority of demuxers ever set need_context_update at all. > > It's not exactly a massive context, so i don't think it's a problem. But > if you prefer, i could add an FF_INFMT_FLAG_ for this.
Actually, it is worse: It is legal for the codec id to change upon need_context_update and then the BSF would still be configured for the old BSF. Anyway, an FF_INFMT_FLAG flag is overkill for this: Just reset the extract_extradata.inited flag. - Andreas _______________________________________________ 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".