#!/bin/dash
echo Convert from...
read ext
echo Convert to...
read toext
for i in *.$ext;
do name=`echo "$i" | grep -E '(.+?)(\.[^.]*$|$)'`
	echo "$name"
	ffmpeg -i "$i" "${name}.$toext" -movflags use_metadata_tags
done
while true; do
	read -p "Delete original files? " yn
	case $yn in
		[Yy]* ) rm *.$ext; exit;;
		[Nn]* ) exit;;
		* ) printf "Please answer yes or no. ";;
	esac
done