[FFmpeg-devel] [PATCH 19/25] fftools/ffmpeg: report new streams from the input thread

[Andreas Rheinhardt]

Anton Khirnov:
> This avoids a potential race with the demuxer adding new streams. It is
> also more efficient, since we no longer do inter-thread transfers of
> packets that will be just discarded.
> ---
>  fftools/ffmpeg.c       | 22 ----------------------
>  fftools/ffmpeg_demux.c | 23 +++++++++++++++++++++++
>  2 files changed, 23 insertions(+), 22 deletions(-)
> 
> diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
> index 1393ca9c1e..37f52f0208 100644
> --- a/fftools/ffmpeg.c
> +++ b/fftools/ffmpeg.c
> @@ -3277,21 +3277,6 @@ static int init_output_stream(OutputStream *ost, AVFrame *frame,
>      return ret;
>  }
>  
> -static void report_new_stream(int input_index, AVPacket *pkt)
> -{
> -    InputFile *file = input_files[input_index];
> -    AVStream *st = file->ctx->streams[pkt->stream_index];
> -
> -    if (pkt->stream_index < file->nb_streams_warn)
> -        return;
> -    av_log(file->ctx, AV_LOG_WARNING,
> -           "New %s stream %d:%d at pos:%"PRId64" and DTS:%ss\n",
> -           av_get_media_type_string(st->codecpar->codec_type),
> -           input_index, pkt->stream_index,
> -           pkt->pos, av_ts2timestr(pkt->dts, &st->time_base));
> -    file->nb_streams_warn = pkt->stream_index + 1;
> -}
> -
>  static int transcode_init(void)
>  {
>      int ret = 0, i, j, k;
> @@ -3831,13 +3816,6 @@ static int process_input(int file_index)
>  
>      reset_eagain();
>  
> -    /* the following test is needed in case new streams appear
> -       dynamically in stream : we ignore them */
> -    if (pkt->stream_index >= ifile->nb_streams) {
> -        report_new_stream(file_index, pkt);
> -        goto discard_packet;
> -    }
> -
>      ist = input_streams[ifile->ist_index + pkt->stream_index];
>  
>      ist->data_size += pkt->size;
> diff --git a/fftools/ffmpeg_demux.c b/fftools/ffmpeg_demux.c
> index f9bd6d47fe..66cb6ebd5f 100644
> --- a/fftools/ffmpeg_demux.c
> +++ b/fftools/ffmpeg_demux.c
> @@ -20,6 +20,7 @@
>  
>  #include "libavutil/error.h"
>  #include "libavutil/time.h"
> +#include "libavutil/timestamp.h"
>  #include "libavutil/thread.h"
>  #include "libavutil/threadmessage.h"
>  
> @@ -27,6 +28,20 @@
>  
>  #include "libavformat/avformat.h"
>  
> +static void report_new_stream(InputFile *file, AVPacket *pkt)
> +{
> +    AVStream *st = file->ctx->streams[pkt->stream_index];

Missing const on st and pkt.

> +
> +    if (pkt->stream_index < file->nb_streams_warn)
> +        return;
> +    av_log(file->ctx, AV_LOG_WARNING,
> +           "New %s stream %d:%d at pos:%"PRId64" and DTS:%ss\n",
> +           av_get_media_type_string(st->codecpar->codec_type),
> +           file->index, pkt->stream_index,
> +           pkt->pos, av_ts2timestr(pkt->dts, &st->time_base));
> +    file->nb_streams_warn = pkt->stream_index + 1;
> +}
> +
>  static void *input_thread(void *arg)
>  {
>      InputFile *f = arg;
> @@ -51,6 +66,14 @@ static void *input_thread(void *arg)
>                               f->ctx->streams[pkt->stream_index]);
>          }
>  
> +        /* the following test is needed in case new streams appear
> +           dynamically in stream : we ignore them */
> +        if (pkt->stream_index >= f->nb_streams) {
> +            report_new_stream(f, pkt);
> +            av_packet_unref(pkt);
> +            continue;
> +        }
> +
>          queue_pkt = av_packet_alloc();
>          if (!queue_pkt) {
>              av_packet_unref(pkt);