[FFmpeg-user] Question about splitting video with dvd_nav_packet data streams

[Carl Eugen Hoyos]

David Favor <david <at> davidfavor.com> writes:

> >> 1) adjust volume
> >> 2) reduce bitrate
> >> 3) retain all data streams (varies 1-3 data streams/VOB file)

> ffmpeg -y -i VTS_01_0.VOB -c:a pcm_s16le -ar 44100 -ac 2 
> foo.wav -map 0:1 -c:v copy foo.vob -map 0:1 -c:d copy foo.data

(Complete, uncut console output missing.)

Why do want to output a file "foo.wav"?
If your goal is to have an input vob file, adjust its volume, 
reduce its video bitrate (and copy some other streams from 
input to output), why should there be a wav file involved?

The same for foo.vob: Why don't you reencode with your 
desired target bitrate?

>     [NULL  <at>  0x7fb0f2038600] Unable to find a suitable 
> output format for 'foo.data'

If you want to keep the data streams from an input vob file, 
your output file has be a vob file as well.

Carl Eugen