Re: [FFmpeg-user] Duplication of time stamps when concatenating .mkv files
On date Tuesday 2015-02-03 13:16:00 -0800, Luke Paone wrote: Hi, I am running into some issues when splitting and then concatenating files using ffmpeg. I am using the following command line to split the files: [...] Here is the FFPROBE out put for 2 frames after the merge: ... [FRAME] media_type=video key_frame=0 pkt_pts=24958 pkt_pts_time=24.958000 pkt_dts=24958 pkt_dts_time=24.958000 best_effort_timestamp=24958 best_effort_timestamp_time=24.958000 pkt_duration=N/A pkt_duration_time=N/A pkt_pos=18554505 pkt_size=25065 width=1920 height=1080 pix_fmt=yuv420p sample_aspect_ratio=1:1 pict_type=P coded_picture_number=0 display_picture_number=0 interlaced_frame=0 top_field_first=0 repeat_pict=0 [/FRAME] [FRAME] media_type=video key_frame=1 pkt_pts=24958 pkt_pts_time=24.958000 pkt_dts=24958 pkt_dts_time=24.958000 best_effort_timestamp=24958 best_effort_timestamp_time=24.958000 pkt_duration=N/A pkt_duration_time=N/A pkt_pos=18579594 pkt_size=98654 width=1920 height=1080 pix_fmt=yuv420p sample_aspect_ratio=1:1 pict_type=I coded_picture_number=0 display_picture_number=0 interlaced_frame=0 top_field_first=0 repeat_pict=0 [/FRAME] My guess is that it could be related to the fact that there is no frame/packet duration in the first frame. The frame duration can only be guessed from the next frame (it will be pts2-pts1), but that information is lost when segmenting the file. I think you should file an issue on trac, possibly providing a sample and a reproducible use-case. ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
Re: [FFmpeg-user] Duplication of time stamps when concatenating .mkv files
Did you try to use the reset_timestamps segment option? Thanks for responding. I tried this but got the same result. As you can see from the output I provided in the first post, I used this command when splitting the video up. This time, I used it when merging (which I'm guessing is what your suggestion was) and got the same result. Any other ideas? ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
Re: [FFmpeg-user] Duplication of time stamps when concatenating .mkv files
On date Tuesday 2015-02-03 13:16:00 -0800, Luke Paone wrote: Hi, I am running into some issues when splitting and then concatenating files using ffmpeg. I am using the following command line to split the files: ffmpeg -i D:\Videos\SwP\sp.webm -codec copy -f segment -segment_time 22 -reset_timestamps 1 D:\Videos\SplitTest\swp_%04d.webm and the output is: [...] My issue is that after the merge, the duration of the video is shorter than the original file by 7 frames, which is the number of merges that happened between the 8 files that came out after the split. I used mkvinfo to look at the details of the .webm file and found that the problem is that ffmpeg is giving the first frame of the second part of a merged video the same time stamp as the last frame of the first part. Therefore I have duplicate time stamps at the point of every merge and I end up loosing a frame because of it. [...] Has anyone run into this issue before? Am I missing something? I tried looking on the forums and in the ffmpeg trac for a bug but was unable to find anything. Any help here would be appreciated. Did you try to use the reset_timestamps segment option? ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
