[FFmpeg-devel] [PATCH 24/35] fftools/ffmpeg: use the sync queues to handle -frames

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Thu Jun 16 23:33:46 EEST 2022


Anton Khirnov:
> Same issues apply to it as to -shortest.
> 
> Changes the results of the following tests:
> - matroska-flac-extradata-update
>   The test reencodes two input FLAC streams into three output FLAC
>   streams. The last output stream is limited to 8 frames. The current
>   code results in the first two output streams having 12 frames, after
>   this commit all three streams have 8 frames and are the same length.
>   This new result is better, since it is predictable.

The point of the test was that only one stream is limited so that one
can see the extradata update directly in the test result: The unlimited
streams have a different extradata than the limited stream (because said
extradata contains an md5 of the decoded data). So it is expected that
the extradata hashes of the first two streams coincide and differ from
the hash of the last stream.
(The current test results btw show an imperfection: The extradata of the
last stream is not updated, as the encoder is not flushed (or the flush
packet does not arrive at the muxer). Fixing this (as seems to be the
case) is good.)

> - mkv-1242
>   The test streamcopies one video and one audio stream, video is limited
>   to 11 frames. The new result shortens the audio stream so that it is
>   not longer than the video.
> ---
>  fftools/ffmpeg.c                              |  6 ------
>  fftools/ffmpeg_mux.c                          | 10 +---------
>  fftools/ffmpeg_opt.c                          | 18 ++++++++++++++---
>  fftools/sync_queue.c                          | 20 +++++++++++++++++++
>  fftools/sync_queue.h                          |  7 +++++++
>  tests/ref/fate/matroska-flac-extradata-update | 16 +++++----------
>  tests/ref/fate/mkv-1242                       |  3 ---
>  7 files changed, 48 insertions(+), 32 deletions(-)
> 
> diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
> index 1a14637ece..a471fa0f8f 100644
> --- a/fftools/ffmpeg.c
> +++ b/fftools/ffmpeg.c
> @@ -3467,12 +3467,6 @@ static int need_output(void)
>  
>          if (ost->finished || of_finished(of))
>              continue;
> -        if (ost->frame_number >= ost->max_frames) {
> -            int j;
> -            for (j = 0; j < of->ctx->nb_streams; j++)
> -                close_output_stream(output_streams[of->ost_index + j]);
> -            continue;
> -        }
>  
>          return 1;
>      }
> diff --git a/fftools/ffmpeg_mux.c b/fftools/ffmpeg_mux.c
> index 641bdb98b0..56444770bf 100644
> --- a/fftools/ffmpeg_mux.c
> +++ b/fftools/ffmpeg_mux.c
> @@ -237,19 +237,11 @@ void of_submit_packet(OutputFile *of, AVPacket *pkt, OutputStream *ost)
>  
>      if (pkt) {
>          /*
> -         * Audio encoders may split the packets --  #frames in != #packets out.
> -         * But there is no reordering, so we can limit the number of output packets
> -         * by simply dropping them here.
>           * Counting encoded video frames needs to be done separately because of
>           * reordering, see do_video_out().
>           */
> -        if (!(st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && ost->encoding_needed)) {
> -            if (ost->frame_number >= ost->max_frames) {
> -                av_packet_unref(pkt);
> -                return;
> -            }
> +        if (!(st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && ost->encoding_needed))
>              ost->frame_number++;
> -        }
>      }
>  
>      if (of->mux->header_written) {
> diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c
> index 2cd4d42f2a..22eb558ff3 100644
> --- a/fftools/ffmpeg_opt.c
> +++ b/fftools/ffmpeg_opt.c
> @@ -2331,6 +2331,7 @@ static int init_complex_filters(void)
>  static int setup_sync_queues(OutputFile *of, AVFormatContext *oc, int64_t buf_size_us)
>  {
>      int nb_av_enc = 0, nb_interleaved = 0;
> +    int limit_frames = 0, limit_frames_av_enc = 0;
>  
>  #define IS_AV_ENC(ost, type)  \
>      (ost->encoding_needed && (type == AVMEDIA_TYPE_VIDEO || type == AVMEDIA_TYPE_AUDIO))
> @@ -2345,14 +2346,19 @@ static int setup_sync_queues(OutputFile *of, AVFormatContext *oc, int64_t buf_si
>  
>          nb_interleaved += IS_INTERLEAVED(type);
>          nb_av_enc      += IS_AV_ENC(ost, type);
> +
> +        limit_frames        |=  ost->max_frames < INT64_MAX;
> +        limit_frames_av_enc |= (ost->max_frames < INT64_MAX) && IS_AV_ENC(ost, type);
>      }
>  
> -    if (!(nb_interleaved > 1 && of->shortest))
> +    if (!((nb_interleaved > 1 && of->shortest) ||
> +          (nb_interleaved > 0 && limit_frames)))
>          return 0;
>  
> -    /* if we have more than one encoded audio/video streams, then we
> +    /* if we have more than one encoded audio/video streams, or at least
> +     * one encoded audio/video stream is frame-limited, then we
>       * synchronize them before encoding */
> -    if (nb_av_enc > 1) {
> +    if ((of->shortest && nb_av_enc > 1) || limit_frames_av_enc) {
>          of->sq_encode = sq_alloc(SYNC_QUEUE_FRAMES, buf_size_us);
>          if (!of->sq_encode)
>              return AVERROR(ENOMEM);
> @@ -2371,6 +2377,9 @@ static int setup_sync_queues(OutputFile *of, AVFormatContext *oc, int64_t buf_si
>              ost->sq_frame = av_frame_alloc();
>              if (!ost->sq_frame)
>                  return AVERROR(ENOMEM);
> +
> +            if (ost->max_frames != INT64_MAX)
> +                sq_limit_frames(of->sq_encode, ost->sq_idx_encode, ost->max_frames);
>          }
>      }
>  
> @@ -2391,6 +2400,9 @@ static int setup_sync_queues(OutputFile *of, AVFormatContext *oc, int64_t buf_si
>              ost->sq_idx_mux = sq_add_stream(of->sq_mux);
>              if (ost->sq_idx_mux < 0)
>                  return ost->sq_idx_mux;
> +
> +            if (ost->max_frames != INT64_MAX)
> +                sq_limit_frames(of->sq_mux, ost->sq_idx_mux, ost->max_frames);
>          }
>      }
>  
> diff --git a/fftools/sync_queue.c b/fftools/sync_queue.c
> index 49f0600b6c..08c3cf4f2a 100644
> --- a/fftools/sync_queue.c
> +++ b/fftools/sync_queue.c
> @@ -36,6 +36,9 @@ typedef struct SyncQueueStream {
>      int64_t          head_ts;
>      /* no more frames will be sent for this stream */
>      int              finished;
> +
> +    uint64_t         frames_sent;
> +    uint64_t         frames_max;
>  } SyncQueueStream;
>  
>  struct SyncQueue {
> @@ -264,6 +267,10 @@ int sq_send(SyncQueue *sq, unsigned int stream_idx, SyncQueueFrame frame)
>  
>      stream_update_ts(sq, stream_idx, ts);
>  
> +    st->frames_sent++;
> +    if (st->frames_sent >= st->frames_max)
> +        finish_stream(sq, stream_idx);
> +
>      return 0;
>  }
>  
> @@ -362,6 +369,7 @@ int sq_add_stream(SyncQueue *sq)
>       * streams forever; cf. overflow_heartbeat() */
>      st->tb      = (AVRational){ 1, 1 };
>      st->head_ts = AV_NOPTS_VALUE;
> +    st->frames_max = UINT64_MAX;
>  
>      return sq->nb_streams++;
>  }
> @@ -381,6 +389,18 @@ void sq_set_tb(SyncQueue *sq, unsigned int stream_idx, AVRational tb)
>      st->tb = tb;
>  }
>  
> +void sq_limit_frames(SyncQueue *sq, unsigned int stream_idx, uint64_t frames)
> +{
> +    SyncQueueStream *st;
> +
> +    av_assert0(stream_idx < sq->nb_streams);
> +    st = &sq->streams[stream_idx];
> +
> +    st->frames_max = frames;
> +    if (st->frames_sent >= st->frames_max)
> +        finish_stream(sq, stream_idx);
> +}
> +
>  SyncQueue *sq_alloc(enum SyncQueueType type, int64_t buf_size_us)
>  {
>      SyncQueue *sq = av_mallocz(sizeof(*sq));
> diff --git a/fftools/sync_queue.h b/fftools/sync_queue.h
> index e08780b7bf..7beddf8c4a 100644
> --- a/fftools/sync_queue.h
> +++ b/fftools/sync_queue.h
> @@ -63,6 +63,13 @@ int sq_add_stream(SyncQueue *sq);
>   */
>  void sq_set_tb(SyncQueue *sq, unsigned int stream_idx, AVRational tb);
>  
> +/**
> + * Limit the number of output frames for stream with index stream_idx
> + * to max_frames.
> + */
> +void sq_limit_frames(SyncQueue *sq, unsigned int stream_idx,
> +                     uint64_t max_frames);
> +
>  /**
>   * Submit a frame for the stream with index stream_idx.
>   *
> diff --git a/tests/ref/fate/matroska-flac-extradata-update b/tests/ref/fate/matroska-flac-extradata-update
> index b0276f734d..84dcc9c1d0 100644
> --- a/tests/ref/fate/matroska-flac-extradata-update
> +++ b/tests/ref/fate/matroska-flac-extradata-update
> @@ -1,8 +1,8 @@
> -56ff5763fd81ad3bc02c22402cd685e2 *tests/data/fate/matroska-flac-extradata-update.matroska
> -2008 tests/data/fate/matroska-flac-extradata-update.matroska
> -#extradata 0:       34, 0x7acb09e7
> -#extradata 1:       34, 0x7acb09e7
> -#extradata 2:       34, 0x443402dd
> +8ec02dffd603f44e08b2ae3b81a0d5a0 *tests/data/fate/matroska-flac-extradata-update.matroska
> +1816 tests/data/fate/matroska-flac-extradata-update.matroska
> +#extradata 0:       34, 0x93650c81
> +#extradata 1:       34, 0x93650c81
> +#extradata 2:       34, 0x93650c81
>  #tb 0: 1/1000
>  #media_type 0: audio
>  #codec_id 0: flac
> @@ -42,9 +42,3 @@
>  0,        672,        672,       96,       26, 0x50dd042e
>  1,        672,        672,       96,       26, 0x50dd042e
>  2,        672,        672,       96,       26, 0x50dd042e
> -0,        768,        768,       96,       26, 0x53de0499
> -1,        768,        768,       96,       26, 0x53de0499
> -0,        864,        864,       96,       26, 0x53df04b4
> -1,        864,        864,       96,       26, 0x53df04b4
> -0,        960,        960,       42,       26, 0x5740044b
> -1,        960,        960,       42,       26, 0x5740044b
> diff --git a/tests/ref/fate/mkv-1242 b/tests/ref/fate/mkv-1242
> index e025701093..1d1a227832 100644
> --- a/tests/ref/fate/mkv-1242
> +++ b/tests/ref/fate/mkv-1242
> @@ -42,6 +42,3 @@
>  1,        383,        383,       21,      325, 0xcd7a9fd6
>  1,        404,        404,       22,      359, 0x6edeb91c
>  1,        426,        426,       21,      333, 0xb8999fb7
> -1,        447,        447,       21,      317, 0xf2589e1a
> -1,        468,        468,       21,      319, 0x82ed9572
> -1,        489,        489,       22,      473, 0xea54e696



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