[FFmpeg-user] DV playback rate issues, timecode is invalid

Stuart Robinson Stuart.Robinson at ed.ac.uk
Thu Jan 19 14:47:45 EET 2023


This is raw dv capture from the firewire by ffmpeg, it hasn't been remuxed yet.

Are you sure it is playing back at regular speed? ffplay is playing it slow for me, I have tried rewrapping to mov as suggested with latest git head (which was more helpful as it shows PARAM_CHANGE may be an issue?) and your recommendation:

ffmpeg -i LL_Tape_13.dv -map 0 -c:v copy  -c:a pcm_s16le -ar 48000 -to 00:01:00 Test1.mov
ffmpeg version 2022-11-21-git-459527108a-full_build-www.gyan.dev Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 12.1.0 (Rev2, Built by MSYS2 project)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libaom --enable-libjxl --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libvpl --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
  libavutil      57. 42.100 / 57. 42.100
  libavcodec     59. 52.102 / 59. 52.102
  libavformat    59. 34.101 / 59. 34.101
  libavdevice    59.  8.101 / 59.  8.101
  libavfilter     8. 50.101 /  8. 50.101
  libswscale      6.  8.112 /  6.  8.112
  libswresample   4.  9.100 /  4.  9.100
  libpostproc    56.  7.100 / 56.  7.100
[dv @ 000001c72fc2f840] Detected timecode is invalid
[dv @ 000001c72fc2f840] Estimating duration from bitrate, this may be inaccurate
Input #0, dv, from 'LL_Tape_13.dv':
  Duration: 01:19:12.04, start: 0.000000, bitrate: 28800 kb/s
  Stream #0:0: Video: dvvideo, yuv420p, 720x576 [SAR 16:15 DAR 4:3], 25000 kb/s, 25 fps, 25 tbr, 25 tbn
  Stream #0:1: Audio: pcm_s16le, 32000 Hz, stereo, s16, 1024 kb/s
  Stream #0:2: Audio: pcm_s16le, 32000 Hz, stereo, s16, 1024 kb/s
File 'Test1.mov' already exists. Overwrite? [y/N] y
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (pcm_s16le (native) -> pcm_s16le (native))
  Stream #0:2 -> #0:2 (pcm_s16le (native) -> pcm_s16le (native))
Press [q] to stop, [?] for help
Output #0, mov, to 'Test1.mov':
  Metadata:
    encoder         : Lavf59.34.101
  Stream #0:0: Video: dvvideo (dvcp / 0x70637664), yuv420p, 720x576 [SAR 16:15 DAR 4:3], q=2-31, 25000 kb/s, 25 fps, 25 tbr, 12800 tbn
  Stream #0:1: Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, stereo, s16, 1536 kb/s (default)
    Metadata:
      encoder         : Lavc59.52.102 pcm_s16le
  Stream #0:2: Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, stereo, s16, 1536 kb/s
    Metadata:
      encoder         : Lavc59.52.102 pcm_s16le
[pcm_s16le @ 000001c72fc48180] This decoder does not support parameter changes, but PARAM_CHANGE side data was sent to it.
[pcm_s16le @ 000001c72fc48180] Error applying parameter changes.
[pcm_s16le @ 000001c72fc48180] This decoder does not support parameter changes, but PARAM_CHANGE side data was sent to it.
[pcm_s16le @ 000001c72fc48180] Error applying parameter changes.



--

Thanks,

        Stuart Robinson,

        AV Technician,

        Sound Lab,

        School of Scottish Studies,

        University of Edinburgh,

        29 George Square,

        Edinburgh,

        EH8 9LD



        0131 651 5001





The University of Edinburgh is a charitable body, registered in

Scotland, with registration number SC005336.

________________________________
From: ffmpeg-user <ffmpeg-user-bounces at ffmpeg.org> on behalf of Dragan Randjelovic <logicomyu at gmail.com>
Sent: 19 January 2023 10:37
To: FFmpeg user questions <ffmpeg-user at ffmpeg.org>
Subject: Re: [FFmpeg-user] DV playback rate issues, timecode is invalid

This email was sent to you by someone outside the University.
You should only click on links or attachments if you are certain that the email is genuine and the content is safe.

>From my experience with dv and dvcam tapes I would recommend capturing DV
with  Enosoft DV Processor  in a raw dv stream (extension *.dv)
and then process it with ffmpeg or ffmbc.

However, the problem that you are experiencing might be related to the
audio resampling, since video goes normally as far as I can see.

Mind that DV cam specification supports 4 channels at 32Khz and 12 bits, or
2 channels at 48Khz 16bit.

therefore when you map streams from avi or .dv file put something like
this: ffmpeg -i "file.dv" -map 0 -c:v copy -c:a pcm_s16le outputfile.mov
(or outputfile.mxf)
(resampling will be invoked automatically or you may specify it with -ar
48000 or using sox library)

You may transcode outputfile  to whatever format you like or keep it like
that as intermediate format suitable for editing.

It looks to me that audio resampling was not done correctly prior to muxing.

Regards.
Dragan

On Thu, Jan 19, 2023 at 10:05 AM Stuart Robinson <Stuart.Robinson at ed.ac.uk>
wrote:

>  I am having terrible trouble with a long play DV I have captured that I
> am trying to transcode. It seems to be playing back slowly regardless of
> what I've tried. The original also plays back strangely, it was captured
> with ffmpeg from a dv camcorder.
>
>
>
> https://drive.google.com/file/d/1ya2C6JmbBQuRUJ_U-fJT8XODYVw0U1kr/view?usp=sharing
> [
> https://lh3.googleusercontent.com/2Z8CVgH_AoIH1LrOrsKKyOeyPmv6bNovZD9akGxW3FD_b0aqhfwUxCGUHIzzrcPW1Tg=w1200-h630-p
> ]<
> https://drive.google.com/file/d/1ya2C6JmbBQuRUJ_U-fJT8XODYVw0U1kr/view?usp=sharing
> >
> Test1.dv<
> https://drive.google.com/file/d/1ya2C6JmbBQuRUJ_U-fJT8XODYVw0U1kr/view?usp=sharing
> >
> drive.google.com
> Can someone take a look and let me know what might help? Are the first few
> frames throwing it off somehow?
>
> Thanks for any help.
>
> Stuart
>
> --
>
> Thanks,
>
>         Stuart Robinson,
>
>         AV Technician,
>
>         Sound Lab,
>
>         School of Scottish Studies,
>
>         University of Edinburgh,
>
>         29 George Square,
>
>         Edinburgh,
>
>         EH8 9LD
>
>
>
>         0131 651 5001
>
>
>
>
>
> The University of Edinburgh is a charitable body, registered in
>
> Scotland, with registration number SC005336.
>
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
>
_______________________________________________
ffmpeg-user mailing list
ffmpeg-user at ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".


More information about the ffmpeg-user mailing list