[FFmpeg-devel] [PATCH 2/2] avformat/hls: Fix probing mpegts audio streams that use probing

[Anssi Hannula]

05.11.2016, 19:27, Hendrik Leppkes kirjoitti:
> On Sat, Nov 5, 2016 at 5:39 PM, Anssi Hannula <anssi.hannula at iki.fi> wrote:
>> Commit 04964ac311abe670f ("avformat/hls: Fix missing streams in some
>> cases with MPEG TS") caused a regression where subdemuxer streams that
>> use probing (e.g. dts/eac3/mp2 in mpegts) no longer get probed properly.
>>
>> This is because the codec parameters from the subdemuxer stream, once
>> probed, are not passed on to the main stream.
>>
>> Fix that by updating the codec parameters if the codec id changes.
>>
>> Signed-off-by: Anssi Hannula <anssi.hannula at iki.fi>
>> ---
>>  libavformat/hls.c | 12 +++++++++++-
>>  1 file changed, 11 insertions(+), 1 deletion(-)
>>
>> diff --git a/libavformat/hls.c b/libavformat/hls.c
>> index 6fb652c..8527f33 100644
>> --- a/libavformat/hls.c
>> +++ b/libavformat/hls.c
>> @@ -1950,6 +1950,8 @@ static int hls_read_packet(AVFormatContext *s, AVPacket *pkt)
>>      /* If we got a packet, return it */
>>      if (minplaylist >= 0) {
>>          struct playlist *pls = c->playlists[minplaylist];
>> +        AVStream *ist;
>> +        AVStream *st;
>>
>>          ret = update_streams_from_subdemuxer(s, pls);
>>          if (ret < 0) {
>> @@ -1972,8 +1974,11 @@ static int hls_read_packet(AVFormatContext *s, AVPacket *pkt)
>>              return AVERROR_BUG;
>>          }
>>
>> +        ist = pls->ctx->streams[pls->pkt.stream_index];
>> +        st = pls->main_streams[pls->pkt.stream_index];
>> +
>>          *pkt = pls->pkt;
>> -        pkt->stream_index = pls->main_streams[pls->pkt.stream_index]->index;
>> +        pkt->stream_index = st->index;
>>          reset_packet(&c->playlists[minplaylist]->pkt);
>>
>>          if (pkt->dts != AV_NOPTS_VALUE)
>> @@ -1981,6 +1986,11 @@ static int hls_read_packet(AVFormatContext *s, AVPacket *pkt)
>>                                              pls->ctx->streams[pls->pkt.stream_index]->time_base,
>>                                              AV_TIME_BASE_Q);
>>
>> +        /* There may be more situations where this would be useful, but this at least
>> +         * handles newly probed codecs properly (i.e. request_probe by mpegts). */
>> +        if (ist->codecpar->codec_id != st->codecpar->codec_id)
>> +            set_stream_info_from_input_stream(st, pls, ist);
>> +
> 
> A better solution would be checking
> ist->internal->need_context_update, and also setting this in the
> output stream when you copy params over, so the generic code knows
> things changed.

AFAICS that flag has already been handled & cleared by
read_frame_internal() at this point.

So I'll do what Andreas suggested and just set it to 1 here (or in
set_stream_in_from_input_stream), unless I'm missing something...

-- 
Anssi Hannula