I have some .avi files that have multiple audio tracks and the default audio track is in a foreign language. I'm not seeking to remove the other track, but merely change some default flag within it so that, when I open it, it plays track 2, or whatever.
I dont want to create any new files, I shouldn't have to do anything like that, and with .mkvs this was really simple.
So I'm wondering if it is also possible to [reasonably simply] modify the contents of an .avi
I used AVIdemux. It does it in seconds so it's not fully 'demuxing', only changing the preferred audio track (or simply deleting the one you don't want) and making the internal parts of the AVI container file mesh properly. It's a free program - http://sourceforge.net/projects/avidemux/?source=dlp
note: The program obviously has demuxing capabilities.
Why can't you create new files? Just use ffmpeg
In command prompt:
ffmpeg -i input.avi -map 0:v:0 -map 0:a:1 -map 0:a:0 -c copy outputxxxxx.avi
ren *xxxxx.avi *.avi
I recommend Rapid Environment Editor in administrator mode to add the environment variable.
The ffmpeg command means map video 0 of input 0 to video 0, map audio 1 of input 0 to audio 0 and map audio 0 of input 0 to audio 1
I do not know how to change the header to designate a different default audio stream in the file. I have always used Virtual Dub to Remove the second stream and pick a specific stream for output. Or to load a seperate audio file in after processing in an audio program.
Virtual Dub mod though, was able to work with multiple audio streams more effectivly http://www.videohelp.com/tools/VirtualdubMOD With virtual Dub mod you can see and change the audio streams in the audio section.
In both programs there is no requirement to re-encode either the audio or the video. If you select Direct Stream it is just a matter of passing the whole video through and re-writing it. Takes a lot more time than changing a header, but it is quick enough.
This info is for windows systems, you did not list what system this is to be done on?
