FLAC to MP3 Conversion

#!/usr/bin/python

import subprocess
import eyed3
import os
import os.path
import re
import struct
import getopt

temp_tags = r"/tmp/___TAGS___.utf8"
temp_cover = r"/tmp/___COVER___.jpg"

def apic_from_unicode_to_latin1(filename):
    data = open(filename, "rb").read()

    match = re.search('APIC(......)\x01image/jpeg\x00\x03\xff\xfe\x00\x00', data)
    if match:
        header = match.group(1)

        # Just inject FIX as picture description to keep same frame size!
        old = 'APIC' + header + '\x01image/jpeg\x00\x03\xff\xfe\x00\x00'
        new = 'APIC' + header + '\x00image/jpeg\x00\x03FIX\x00'
        data = data.replace(old, new)

        fh = open(filename, "wb")
        fh.write(data)
        fh.close()

class TagData(object):
    def __init__(self):
        self.title = None
        self.album = None
        self.track_num = None
        self.artist = None
        self.genre = None
        self.date = None
        self.album_artist = None

    def read_flac_tags(self, filename):
        subprocess.call(["metaflac", "--no-utf8-convert", "--export-tags-to=" + temp_tags, filename])
        fh = open(temp_tags, "rb")
        for line in fh:
            match = re.match(r'^TITLE=(.*)', line.decode('UTF-8'), re.IGNORECASE)
            if match:
                self.title = match.group(1)
            match = re.match(r'^ALBUM=(.*)', line.decode('UTF-8'), re.IGNORECASE)
            if match:
                self.album = match.group(1)
            match = re.match(r'^TRACKNUMBER=(\d*)', line.decode('UTF-8'), re.IGNORECASE)
            if match:
                self.track_num = int(match.group(1))
            match = re.match(r'^ARTIST=(.*)', line.decode('UTF-8'), re.IGNORECASE)
            if match:
                self.artist = match.group(1)
            match = re.match(r'^GENRE=(.*)', line.decode('UTF-8'), re.IGNORECASE)
            if match:
                self.genre = match.group(1)
            match = re.match(r'^DATE=(\d*)', line.decode('UTF-8'), re.IGNORECASE)
            if match:
                self.date = int(match.group(1))

        fh.close()

    def write_mp3_tags(self, filename):
        audiofile = eyed3.load(filename)
        audiofile.tag = eyed3.id3.Tag() # Create NEW!
        if self.title:
            audiofile.tag.title = self.title
        if self.album:
            audiofile.tag.album = self.album
        if self.track_num:
            audiofile.tag.track_num = self.track_num
        if self.artist:
            audiofile.tag.artist = self.artist
        if self.genre:
            audiofile.tag.genre = self.genre
        if self.date:
            audiofile.tag.recording_date = self.date # Works if version 2.3
        if self.album_artist:
            audiofile.tag.album_artist = self.album_artist
        audiofile.tag.save(filename, eyed3.id3.ID3_V2_3)

def print_usage(progname):
    print "Usage: %s " % (progname)
    print "-f <FLAC File>"
    print "-a [AlbumArtist]"
    print "-c [Cover Image Path]"
    print "-n [Album Name Override]"

if __name__ == "__main__":
    import sys

    tagdata = TagData()

    # NOTE: Need to filter out empty strings from sys.argv.
    # If not, the parser thinks parsing finishes early.
    try:
        opts, args = getopt.getopt(filter(None, sys.argv[1:]), "hf:a:c:n:", ["help", "flacfile=", "albumartist=", "cover=", "albumname="])
    except getopt.GetoptError as err:
        print str(err)
        print_usage(sys.argv[0])
        sys.exit(1)

    print "Opts:", opts
    print "Args:", args

    filename = None
    album_artist = None
    cover_override = None
    album_name_override = None

    for o, a in opts:
        if o in ("-h", "--help"):
            print_usage(sys.argv[0])
            sys.exit(1)
        elif o in ("-f", "--flacfile"):
            filename = a
            print "FLAC File:", filename
        elif o in ("-a", "--albumartist"):
            album_artist = a
            print "AlbumArtist:", album_artist
        elif o in ("-c", "--cover"):
            cover_override = a
            print "Cover Image Path:", cover_override
        elif o in ("-n", "--albumname"):
            album_name_override = a
            print "Album Name Override:", album_name_override

    if filename == None:
        print_usage(sys.argv[0])
        sys.exit(1)

    # Set optional AlbumArtist.
    if album_artist:
        tagdata.album_artist = unicode(album_artist)

    # Read old tags from FLAC.
    tagdata.read_flac_tags(filename)

    # Set optional album name override, AFTER reading default tags.
    if album_name_override:
        tagdata.album = unicode(album_name_override)

    # Decode FLAC, encode MP3.
    subprocess.call(["flac", "-d", filename, "-o", filename + ".wav"])
    subprocess.call(["lame", "-b", "320", "-h", filename + ".wav", filename + ".mp3"])

    # Write new tags to MP3.
    tagdata.write_mp3_tags(filename + ".mp3")

    # Get cover image from argument, or...
    if cover_override:
        cover_file = cover_override
    else:
        # ...attempt to extract cover image from FLAC file...
        subprocess.call(["metaflac", "--export-picture-to=" + temp_cover, filename])
        cover_file = temp_cover

    # ...then apply it.
    if os.path.isfile(cover_file):
        imagedata = open(cover_file, "rb").read()
        if imagedata.startswith("\xff\xd8\xff"):
            audiofile = eyed3.load(filename + ".mp3")
            audiofile.tag.images.set(3, imagedata, "image/jpeg")
            audiofile.tag.save()
        else:
            print "Warning: Image data is not JPEG."

    # iTunes APIC fix, encoding must be changed to latin1.
    apic_from_unicode_to_latin1(filename + ".mp3")

    # Remove ".flac" part of final MP3 file.
    if os.path.isfile(filename + ".mp3"):
        os.rename(filename + ".mp3", filename.replace(".flac", "") + ".mp3")

    # Remove temporary files.
    if os.path.isfile(filename + ".wav"):
        os.remove(filename + ".wav")
    if os.path.isfile(temp_tags):
        os.remove(temp_tags)
    if os.path.isfile(temp_cover):
        os.remove(temp_cover)