Rebuild MP4

rebuild-all.sh

#!/bin/bash

# this is a script that was made to extract the video and *second* audio stream
# from an all the mp4 files in the current directory and rebuild them to contain
# just the video and the second audio stream

for filename in *.avi; do
		
	ffmpeg -y -i "$filename" -an -vcodec copy video.mp4
	ffmpeg -y -i "$filename" -map 0:2 -vn -acodec copy audio.mp3

	mv "$filename" "$filename.old" 

	ffmpeg -i video.mp4 -i audio.mp3 -vcodec copy -acodec copy "$filename"

done