[FFmpeg-devel] [PATCH] avformat/dashdec: The segments in dash file doesn't read completely when segment's size and duration is very small.

[Steven Liu]

jiangjie <jiangjie618 at gmail.com> 于2024年9月2日周一 16:35写道：
>
> If the segment is very small, avformat_find_stream_info will read all audio/video data in this segment. cur->is_restart_needed is set to 0 later in dash_read_packet function, and no chance to be set to 1 again in the read_data function.
>
> Reproduction:
> ffmpeg -f lavfi -i mandelbrot -f lavfi -i anullsrc -c:v vp8 -g 5 -r 5 -c:a libopus -use_template 0 -seg_duration 1 -t 15 -y test_720.mpd
> ffprobe -show_packets test_720.mpd
>
> The duration of the test_720.mpd file is 15 seconds, but the duration that ffprobe show is small than 15 second.
> ---
>  libavformat/dashdec.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/libavformat/dashdec.c b/libavformat/dashdec.c
> index 63070b77be..12960d0312 100644
> --- a/libavformat/dashdec.c
> +++ b/libavformat/dashdec.c
> @@ -2207,9 +2207,9 @@ static int dash_read_packet(AVFormatContext *s, AVPacket *pkt)
>          if (cur->is_restart_needed) {
>              cur->cur_seg_offset = 0;
>              cur->init_sec_buf_read_offset = 0;
> +            cur->is_restart_needed = 0;
>              ff_format_io_close(cur->parent, &cur->input);
>              ret = reopen_demux_for_component(s, cur);
> -            cur->is_restart_needed = 0;
>          }
>      }
>      return AVERROR_EOF;
> --
> 2.43.0
>
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good catch
LGTM

Thanks
Steven