Convert mp3 to m4r (Apple Tone), limit to 39 seconds for use as iPhone ringtone

itone.zsh

#!/usr/bin/env zsh

if (( ! ${#@} )); then
	print "Convert mp3 to m4r (Apple Tone)"
	print
	print "Usage: $0 file1.mp3 file2.mp3"
	exit 1
fi

tmpdir=$(mktemp -d)

trap 'exit 1' INT
trap 'print Cleaning up...; rm -r $tmpdir' EXIT

for i in $@; do
	print Converting: ${i:r}
	ffmpeg_out=$(ffmpeg -t 39 -i $i -acodec copy $tmpdir/$i 2>&1)
	(( ? )) && {
		print "ffmpeg failed:"
		print -- $ffmpeg_out
		exit 1
	}
	af_out=$(afconvert -v -f m4af -q 127 $tmpdir/$i ${i:r}.m4r)
	(( ? )) && {
		print "afconvert failed:"
		print -- $af_out
		exit 1
	}
done