On Mar 4, 2012 7:12 PM, "Robin Gareus" <robin@gareus.org> wrote:
>
> On 03/04/2012 07:48 PM, James Stone wrote:
> > Hi List,
> >
> > I have a video which needs a bit of eq'ing on the audio side. Can
> > anyone point me in the direction of how to split the file into audio
> > and video so I can apply some treatment to the audio, and then combine
> > them back together again? The video is wmv at the moment, but mplayer
> > doesn't seem to have any problem with it.
> >
>
> #extract audio
> ffmpeg -i orig_video.wmv audio_out.wav
>
> #replace audio
> ffmpeg \
>  -i orig_video.wmv \
>  -i new_audio.wav \
>  -vcodec copy \
>  -map 0.0 -map 1.0 \
>  new_video.wmv
>
>
> Details:  The "map" may be different depending on the .wmv file.
> run `ffprobe` to see which is the video-track in the .wmv file
> usually this is "0.0".
>    Stream #0.0: Video:...
>    Stream #0.1: Audio: ..
> and "1.0" corresponds to the 2nd input file - your new audio.
>
> You may want to add "-acodec wmav2" and "-ar 128k" options for 128kbit/s
> Windows Media Audio 2 or whatever audio-codec/quality your want. `ffmpeg
> -codecs | grep "EA"` gives you a list of available codecs for Encoding
> Audio.
>

Thanks. It is 0:0 and 0:1 and -b:a=192k I found, but I have some sync problems after recombining tho. Any other ideas?

> BTW. Ardour3 with videotimeline patch can do all this for you.
> import,extract,re-encode using ffmpeg.
>
> robin