Hi I have come across a strange issue with concatenating mkv (vp9/libopus) files which have been transcoded from mp4 and the saple rate changed.
Conversion string ffmpeg -v 35 -threads 4 -i /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_1_envsc2_1_envs_vo.mkv -c:v libvpx-vp9 -crf 40 -row-mt 1 -tile-columns 6 -frame-parallel 1 -c:a libopus -b:a 56k -ar 48000 -frame_size 40 -strict -2 -ac 2 -af aresample=48000,volume=1 -vf scale='480:trunc(ow/((1/sar)*dar)/2)*2',setsar='1/1',fps='fps=20' -y -speed 15 -deadline realtime /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_1_envsc2_1_envs_vo_envs_vo.mkv This seems to go normally, however when I then try to concatenate these files I get a short video, eg 47 minutes rather than 2:24 The error is [matroska @ 0x56489ea616c0] Non-monotonous DTS in output stream 0:1; previous: 2855081, current: 2855000; changing to 2855081. This may result in incorrect timestamps in the output file. [concat @ 0x56489e998980] DTS 2855014 < 2855064 out of order [matroska @ 0x56489ea616c0] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 2855064 >= 2855014 Conversion failed! concat file is file /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_1_envsc2_1_envs_vo.mkv duration 0:23:21 file /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_2_envsc2_1_envs_vo.mkv duration 0:24:14 file /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_3_envsc2_1_envs_vo.mkv duration 0:24:04 file /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_4_envsc2_1_envs_vo.mkv duration 0:23:38 file /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_5_envsc2_1_envs_vo.mkv duration 0:24:00 file /srv/data/staging/Doctor_Who_10_3_Frontier_in_Space_6c2_envsc2_1_envs_vo.mkv duration 0:24:46 If I convert to mp4 with aac no issues, but I cant convert the resulting file to mkv vp9/libopus with the same issues. Anyone any ideas what is happening? _______________________________________________ ffmpeg-user mailing list [email protected] https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
