Convert flac to alac.

flac2alac

#!/bin/bash

function flac2alac {
	filename=$(basename "$1" .flac)
	dir=$(dirname "$1")
	artformat="$(metaflac --export-picture-to=- "$1" | file --mime --brief - | awk '{split($1,arr,";"); print arr[1]}')"
	artfile=".art.${filename}"

	echo "Convert $1 ..."

	if [ "$artformat" != "application/x-empty" ]; then
		if [ "$artformat" != "image/png" ] && [ "$artformat" != "image/jpeg" ]; then
			echo "Unknown embedded album art format ${artformat}. Abort." 1>&2
			exit 1
		fi
		metaflac --export-picture-to="${dir}/${artfile}" "$1"
	fi

	ffmpeg $ffmpeg_general_opt -i "$1" -vn -acodec alac "${dir}/${filename}.m4a"
	if [ $? -ne 0 ]; then
		echo "Abort." 2>&1
		exit $?
	fi

	if [ -f "${dir}/${artfile}" ]; then
		atomicparsley "${dir}/${filename}.m4a" --artwork "${dir}/${artfile}" -W
		fail=$?
		rm -f "${dir}/${artfile}"
		if [ $fail -ne 0 ]; then
			echo "Fail to set artwork for ${dir}/${filename}.m4a. Abort." 1>&2
			exit 1
		fi
	fi
}

function convert_folder {
	pushd "$1" > /dev/null
	for filename in *.flac; do
		flac2alac "$filename"
	done
	popd > /dev/null
}

function usage() {
	echo "Convert flac file to alac." 1>&2
	echo "Usage: $(basename "$0") [-h] <file|dir>..." 1>&2
	echo "" 1>&2
	echo "OPTIONS:" 1>&2
	echo "    -h: print help" 1>&2
	echo "    -v: log verbosely. this displays ffmpeg logs" 1>&2
	echo "    -y: always overwrite existing files" 1>&2
	exit 1
}

if [ $# -eq 0 ]; then
	usage
fi

verbose=0
overwrite=0
while getopts 'hvy' arg; do
	case $arg in
		h)
			usage
			;;
		v)
			verbose=1
			;;
		y)
			overwrite=1
			;;
		?)
			usage
			;;
	esac
done

ffmpeg_general_opt="-stats"
if [ $verbose -eq 0 ]; then
	ffmpeg_general_opt="$ffmpeg_general_opt -loglevel fatal"
fi
if [ $overwrite -eq 1 ]; then
	ffmpeg_general_opt="$ffmpeg_general_opt -y"
fi

shift $(($OPTIND - 1))
for arg in "$@"; do
	if [ -d "$arg" ]; then
		convert_folder "$arg"
	fi
	if [ -f "$arg" ]; then
		flac2alac "$arg"
	fi
done