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I have large MPEG-TS file that I am converting to MP4 using the below command. If I seek to the same time in the video in both the MP4 and the TS file, the MP4 will be a few frames behind the TS file. This get progressively worse the further into the video I seek.

c:\>ffmpeg -y -r 30 -i full-ts.ts -c:v copy -r 30 -an full.mp4
ffmpeg version N-69040-gb23a866 Copyright (c) 2000-2015 the FFmpeg developers
  built on Jan 12 2015 22:02:37 with gcc 4.9.2 (GCC)
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --
enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinge
r --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-
libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
  libavutil      54. 16.100 / 54. 16.100
  libavcodec     56. 20.100 / 56. 20.100
  libavformat    56. 18.101 / 56. 18.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5.  7.100 /  5.  7.100
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mpegts, from 'full-ts.ts':
  Duration: 00:11:25.75, start: 1.424000, bitrate: 3407 kb/s
  Program 1
    Metadata:
      service_name    : Service01
      service_provider: FFmpeg
    Stream #0:0[0x100]: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 30 fps, 30 tbr, 90k tbn, 60 tbc
    Stream #0:1[0x101]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp, 125 kb/s
Output #0, mp4, to 'full.mp4':
  Metadata:
    encoder         : Lavf56.18.101
    Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 30 fps, 30 tbr, 15360 tbn, 30 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
frame=20419 fps=0.0 q=-1.0 Lsize=  251660kB time=00:11:25.59 bitrate=3007.0kbits/s
video:251446kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.084929%

I'm confused why the TBN is so large in the output stream. I've tried -copyts, -copytb, all the -vsynch options, but I cannot get seek times to match up on the MP4. Also, the MP4 shows a frame rate of 29.78, whereas the TS file is solid 30/1 using ffprobe.

ffprobe -v error -of flat=s=_ -select_streams v:0 -show_entries stream=avg_frame_rate full.mp4
streams_stream_0_avg_frame_rate="5227264/175529"

ffprobe -v error -of flat=s=_ -select_streams v:0 -show_entries stream=avg_frame_rate full-ts.ts
programs_program_0_streams_stream_0_avg_frame_rate="30/1"
streams_stream_0_avg_frame_rate="30/1" 

Any idea how I can get the seeking on the both containers to show the same frame? Please help!

  • 1
    What happens if you remove the input -r 30? What is the reason for that anyway? Also, you enable stream copy mode with -c:v copy which means the output -r 30 is ignored. – llogan Apr 3 '15 at 23:34
  • @LordNeckbeard - it changes a few things in the output, but I still have the seeking issue. See log @ gist.github.com/andypryor/3b1f123b4c8d6ed3975c , Thank for explaining the -r 30 is not needed, I misunderstood its use, thought I could force mp4 frame rate. – Andy Apr 5 '15 at 2:54
  • 1
    As I understand it, mp4 doesn't store a framerate anywhere, just times between individual frames. So ffprobe looks at the frame times of the first few frames, and assumes the rest of the video is the same. I don't have any ideas to actually solve your problem, though. Except maybe try something other than ffmpeg, like MP4Box. Or even mkvmerge to a .mkv, to see if that works any differently. (and maybe try ffmpeg muxing to something other than mp4. ffmpeg's mp4 muxer might not be perfect.) – Peter Cordes Apr 12 '15 at 2:30
  • The standard video frame rate is 29.97, if you convert to 30fps you will eventually see drift: filmdoctor.net/2010/06/drop-frame-vs-non-drop-frame – screaming drills Sep 15 '15 at 4:19
  • tbn of the output stream is too small 15k. it should be 90k. Seems like discarding of the audio stream is the source of the problem. – Dimitri Podborski Apr 7 '16 at 0:08
3

As per a comment here, removing the -r flag ought to do this properly. You have another -r flag for the input, also. Remove both of them, and it should properly copy the stream as it is into a new container; you may need to remove that -an (disable audio) switch, too. I'm not sure on that:

ffmpeg -y -i full-ts.ts -c:v copy full.mp4

If that fails, also per a comment here, you could try a different output container format.

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