ffmpeg mp3 rename tag or bitrate on demand

ffmpeg.sh

#!/bin/bash

#rename id3 album
#output file with "_.mp3"
for file in myfolder/*.mp3; do
	ffmpeg -i $file -acodec copy -metadata album="Mysite.CoM" "$( sed -e's/\.mp3/_.mp3/g' <<< $file )"
	# convert to 128kbps
	#ffmpeg -i $file -ab 128k "$( sed -e's/\.mp3/_.mp3/g' <<< $file )"
done

#remove file size 0
#move file with "_.mp3" to ".mp3"
for file in myfolder/*.mp3; do
	if [ ! -s $file ] ; then
		rm $file
	fi
	mv $file ${file//_\.mp3/\.mp3}
done