[FFmpeg-devel] [PATCH 1/1] Prevent writing manifest files multiple times

[Jeyapal, Karthick]

On 3/27/19 2:08 AM, joepadmiraal wrote:
> ---
>  libavformat/dashenc.c | 17 ++++++++++++++++-
>  1 file changed, 16 insertions(+), 1 deletion(-)
Sorry for the delayed reply. Thanks for submitting a patch for a very useful optimization. Here are my review comments.

Please add a prefix "libavformat/dashenc : " to the subject line(First line of commit message). 
>
> diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
> index 1b74bce060..e4f7843e03 100644
> --- a/libavformat/dashenc.c
> +++ b/libavformat/dashenc.c
> @@ -144,6 +144,8 @@ typedef struct DASHContext {
>      int ignore_io_errors;
>      int lhls;
>      int master_publish_rate;
> +    int nr_of_streams_to_flush;
> +    int nr_of_streams_flushed;
>  } DASHContext;
>  
>  static struct codec_string {
> @@ -1079,6 +1081,7 @@ static int dash_init(AVFormatContext *s)
>      char *ptr;
>      char basename[1024];
>  
> +    c->nr_of_streams_to_flush = 0;
>      if (c->single_file_name)
>          c->single_file = 1;
>      if (c->single_file)
> @@ -1274,12 +1277,18 @@ static int dash_init(AVFormatContext *s)
>          os->max_pts = AV_NOPTS_VALUE;
>          os->last_dts = AV_NOPTS_VALUE;
>          os->segment_index = 1;
> +
> +        if (s->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
> +            c->nr_of_streams_to_flush++;
>      }
>  
>      if (!c->has_video && c->seg_duration <= 0) {
>          av_log(s, AV_LOG_WARNING, "no video stream and no seg duration set\n");
>          return AVERROR(EINVAL);
>      }
> +
> +    c->nr_of_streams_flushed = 0;
> +
>      return 0;
>  }
>  
> @@ -1565,8 +1574,14 @@ static int dash_flush(AVFormatContext *s, int final, int stream)
>          }
>      }
>  
> -    if (ret >= 0)
> +    if (ret >= 0) {
> +        c->nr_of_streams_flushed++;
> +        if (c->nr_of_streams_flushed != c->nr_of_streams_to_flush)
> +            return ret;
This seems to break support for the case c->has_video is false(audio-only). For that case c->nr_of_streams_to_flush will be 0 and will always satisfy the "if" condition here. Hence manifest will never get written for audio-only use-case.
> +
> +        c->nr_of_streams_flushed = 0;
>          ret = write_manifest(s, final);
> +    }
>      return ret;
>  }
>