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ffmpeg

Wrong audio track by default

Note: This is a bug I would run into after extracting a VOB from a DVD, and running ffmpeg -i movie.vob

ffmpeg lists the audio tracks in reverse order *in some cases*, so be sure to map the right one. See order of 0x8x below for an example.

You can see the streams by ffmpeg output that it is reading and writing to:

    Stream #0.0[0x1e0]: Video: mpeg2video, yuv420p, 720x480 [PAR 32:27 DAR 16:9], 9800 kb/s, 59.94 tb(r)
    Stream #0.1[0x85]: Audio: ac3, 48000 Hz, 5.0, s16, 448 kb/s
    Stream #0.2[0x84]: Audio: ac3, 48000 Hz, stereo, s16, 256 kb/s
    Stream #0.3[0x83]: Audio: ac3, 48000 Hz, quad, s16, 448 kb/s
    Stream #0.4[0x82]: Audio: ac3, 48000 Hz, stereo, s16, 256 kb/s
    Stream #0.5[0x81]: Audio: ac3, 48000 Hz, 5.1, s16, 448 kb/s
    Stream #0.6[0x80]: Audio: ac3, 48000 Hz, stereo, s16, 256 kb/s
Output #0, avi, to 'movie.avi':
    Stream #0.0: Video: mpeg4, yuv420p, 720x480 [PAR 32:27 DAR 16:9], 
q=2-31, 200 kb/s, 59.94 tb(c)
    Stream #0.1: Audio: mp2, 48000 Hz, stereo, s16, 192 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.6 -> #0.1 [sync #0.1]

If you map any of them, you need to map all of them (both audio and video).

ffmpeg -i movie.vob -map 0.0:0.0 -map 0.6:0.1

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