[FFmpeg-user] Question on Segment TImes

Colin Bitterfield colin at bitterfield.com
Sun Apr 5 19:30:10 EEST 2020

The tape deck is a Sony DSR-45 (not the “A” model).

The tapes are pre-recorded studio dubbing masters. When I do ffprobe with avfoundation it produces this output:

    Stream #0:0: Video: dvvideo, yuv411p, 720x480 [SAR 8:9 DAR 4:3], 25000 kb/s, 29.97 fps, 29.97 tbr, 29.97 tbn, 29.97 tbc
    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

I was unable to map anything resemble 0:1 or 0:a:0 coming in from the deck. Once it was in an DV file, it worked as expected.

I had not thought of this before, but perhaps I can map 0:v:1 to audio? Maybe it sees it all as a video.

On Apr 4, 2020, 8:33 PM -0700, FFmpeg user questions <ffmpeg-user at ffmpeg.org>, wrote:
> think this has to do with AVFoundation’s “raw data” option and how audio and video is stored on the actual metallic sublimate tape (iirc, the video/audio/timecode “streams” do not exist as discrete entities, but they are all interleaved into an atomic “DV” tape-format (hence the 1M reported tbn). I’m not sure how AVFoundation splits them up or isolates the detected timecode or decide to join all the streams together, but I presume it’s similar to the audio fixup menu options in FCPX import media window.
> I’m curious if this would work, but have you tried artificially increasing the video size (via framerate, frame size, etc) to make it into what would be considered HDV, or even DVCPRO and try adding the audio streams then? Apparently it supports multiple streams (DVCPRO50, that is)

More information about the ffmpeg-user mailing list