[FFmpeg-user] Timestamp problem?

[Mark Filipak]

Hello,

Is the below a timestamp problem that '-fflags +genpts' is hiding but not really fixing?

This command: ffmpeg -loglevel verbose -fflags +genpts -i "concat:VTS_06_1.VOB|VTS_06_2.VOB|VTS_06_3.VOB|VTS_06_4.VOB|VTS_06_5.VOB" -map 0:v -map 0:a -c:v copy -c:a copy D:\OUT.mkv

completes without error, but only if I include '-fflags +genpts'.

The result without '-fflags +genpts' (http://ffmpeg.org/pipermail/ffmpeg-user/2020-March/047451.html), "Can't write packet with unknown timestamp".

But there seems to be a problem with OUT.mkv because when I try reordering the audio tracks, MKVToolNix remuxes 78% and then stops with "Failed". I've tried several times.

Comments / suggestions are very welcome.

Regards,
Mark.


G:\VIDEO_TS>ffmpeg -loglevel verbose -fflags +genpts -i "concat:VTS_06_1.VOB|VTS_06_2.VOB|VTS_06_3.VOB|VTS_06_4.VOB|VTS_06_5.VOB" -map 0:v -map 0:a -c:v copy -c:a copy "OUT.mkv"
ffmpeg version N-94664-g0821bc4eee Copyright (c) 2000-2019 the FFmpeg developers
   built with gcc 9.1.1 (GCC) 20190807
   configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
   libavutil      56. 33.100 / 56. 33.100
   libavcodec     58. 55.101 / 58. 55.101
   libavformat    58. 31.104 / 58. 31.104
   libavdevice    58.  9.100 / 58.  9.100
   libavfilter     7. 58.101 /  7. 58.101
   libswscale      5.  6.100 /  5.  6.100
   libswresample   3.  6.100 /  3.  6.100
   libpostproc    55.  6.100 / 55.  6.100
[mpeg @ 000001c89af494c0] max_analyze_duration 5000000 reached at 5021489 microseconds st:1
Input #0, mpeg, from 'concat:VTS_06_1.VOB|VTS_06_2.VOB|VTS_06_3.VOB|VTS_06_4.VOB|VTS_06_5.VOB':
   Duration: 01:58:50.14, start: 0.041500, bitrate: 5598 kb/s
     Stream #0:0[0x1bf]: Data: dvd_nav_packet
     Stream #0:1[0x1e0]: Video: mpeg2video (Main), 1 reference frame, yuv420p(tv, top first, left), 720x480 [SAR 32:27 DAR 16:9], Closed Captions, 29.97 fps, 59.94 tbr, 90k tbn, 59.94 tbc
     Stream #0:2[0x81]: Audio: ac3, 48000 Hz, stereo, fltp, 192 kb/s
     Stream #0:3[0x80]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s
File 'OUT.mkv' already exists. Overwrite ? [y/N] y
Output #0, matroska, to 'OUT.mkv':
   Metadata:
     encoder         : Lavf58.31.104
     Stream #0:0: Video: mpeg2video (Main), 1 reference frame (mpg2 / 0x3267706D), yuv420p(tv, top first, left), 720x480 (0x0) [SAR 32:27 DAR 16:9], q=2-31, 29.97 fps, 59.94 tbr, 1k tbn, 90k tbc
     Stream #0:1: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, stereo, fltp, 192 kb/s
     Stream #0:2: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, 5.1(side), fltp, 448 kb/s
Stream mapping:
   Stream #0:1 -> #0:0 (copy)
   Stream #0:2 -> #0:1 (copy)
   Stream #0:3 -> #0:2 (copy)
Press [q] to stop, [?] for help
[mpeg @ 000001c89af494c0] New subtitle stream 0:4 at pos:95102990 and DTS:109.05ss speed=98.4x
[mpeg @ 000001c89af494c0] New subtitle stream 0:5 at pos:95363086 and DTS:109.284s
[mpeg @ 000001c89af494c0] New subtitle stream 0:6 at pos:95406094 and DTS:109.317s
No more output streams to write to, finishing.ime=01:58:38.65 bitrate=5474.6kbits/s speed= 127x
frame=171005 fps=3047 q=-1.0 Lsize= 4765106kB time=01:58:50.11 bitrate=5474.8kbits/s speed= 127x
video:4203191kB audio:557042kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.102361%
Input file #0 (concat:VTS_06_1.VOB|VTS_06_2.VOB|VTS_06_3.VOB|VTS_06_4.VOB|VTS_06_5.VOB):
   Input stream #0:0 (data): 0 packets read (0 bytes);
   Input stream #0:1 (video): 171005 packets read (4304067103 bytes);
   Input stream #0:2 (audio): 222817 packets read (171123456 bytes);
   Input stream #0:3 (audio): 222817 packets read (399288064 bytes);
   Total: 616639 packets (4874478623 bytes) demuxed
Output file #0 (OUT.mkv):
   Output stream #0:0 (video): 171005 packets muxed (4304067103 bytes);
   Output stream #0:1 (audio): 222817 packets muxed (171123456 bytes);
   Output stream #0:2 (audio): 222817 packets muxed (399288064 bytes);
   Total: 616639 packets (4874478623 bytes) muxed
[AVIOContext @ 000001c89b6b3540] Statistics: 8 seeks, 27858 writeouts
[AVIOContext @ 000001c89af53080] Statistics: 4993048720 bytes read, 3 seeks