[FFmpeg-user] How to copy all of 5 audio streams to mp4 file

Moritz Barsnick barsnick at gmx.net
Mon Feb 18 18:06:55 EET 2019


On Mon, Feb 18, 2019 at 16:29:01 +0100, Ulf Zibis wrote:
> >> Also there should be 13 subtitle streams in this video, but I don't find
> >> them here.
> > In VOBs, subtitles tend to appear later in the files. Use large values
> > for "-probesize" and "-analyzeduration" for seeing them (not only when
> > probing, but also when converting).
> >
> > OTOH, your ffmpeg output doesn't report them appearing later, which it
> > should, if it were to find them. So I'm not sure they're there.
> 
> They are detected now, but I don't have them in the output. Is that,
> because I only have transcoded 6 min. this time?

No, they are detected *while* demuxing the input:

> [mpeg @ 0x6d89bc0] New subtitle stream 0:7 at pos:26603534 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:8 at pos:26607630 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:9 at pos:26611726 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:10 at pos:26615822 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:11 at pos:26619918 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:12 at pos:26624014 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:13 at pos:26669070 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:14 at pos:26673166 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:15 at pos:26677262 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:16 at pos:26685454 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:17 at pos:26695694 and DTS:31.16s
> [mpeg @ 0x6d89bc0] New subtitle stream 0:18 at pos:26746894 and DTS:31.2s

ffmpeg needs to detect them *before* demuxing. That's why I told you to
use large values for "-probesize" and "-analyzeduration". They tell
ffmpeg to look deeply into the video before deciding which input
streams are available. Then "-map 0" would pick them up for the
output, or you could select them with "-map 0:s:N".

(Possibly, you can derive useful values for "-probesize" and "-analyzeduration"
from "pos:26746894" and "DTS:31.2s", but I'm not sure. For unknown
input VOBs, you may need to specify the maximum possible values, which
would be 9223372036854775807.)

Cheers,
Moritz


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