Support FLAC output format (#259)

* Convert to .flac option * Embed metadata to FLAC * Update usage help * Write tests
2026-02-11 03:49:33 +00:00 · 2018-04-02 00:47:31 +05:30
parent 7f7c3d6f58
commit 96ab547c5c
8 changed files with 123 additions and 79 deletions
--- a/core/const.py
+++ b/core/const.py
@@ -1,8 +1,33 @@
 import logzero

 _log_format = ("%(color)s%(levelname)s:%(end_color)s %(message)s")
-formatter = logzero.LogFormatter(fmt=_log_format)
+_formatter = logzero.LogFormatter(fmt=_log_format)

 # options
-log = logzero.setup_logger(formatter=formatter)
+log = logzero.setup_logger(formatter=_formatter)
 args = None
+
+# Apple has specific tags - see mutagen docs -
+# http://mutagen.readthedocs.io/en/latest/api/mp4.html
+M4A_TAG_PRESET = { 'album'        : '\xa9alb',
+                   'artist'       : '\xa9ART',
+                   'date'         : '\xa9day',
+                   'title'        : '\xa9nam',
+                   'year'         : '\xa9day',
+                   'originaldate' : 'purd',
+                   'comment'      : '\xa9cmt',
+                   'group'        : '\xa9grp',
+                   'writer'       : '\xa9wrt',
+                   'genre'        : '\xa9gen',
+                   'tracknumber'  : 'trkn',
+                   'albumartist'  : 'aART',
+                   'discnumber'   : 'disk',
+                   'cpil'         : 'cpil',
+                   'albumart'     : 'covr',
+                   'copyright'    : 'cprt',
+                   'tempo'        : 'tmpo',
+                   'lyrics'       : '\xa9lyr' }
+
+TAG_PRESET = {}
+for key in M4A_TAG_PRESET.keys():
+    TAG_PRESET[key] = key
--- a/core/convert.py
+++ b/core/convert.py
@@ -17,16 +17,16 @@ https://trac.ffmpeg.org/wiki/Encode/AAC

 def song(input_song, output_song, folder, avconv=False):
    """ Do the audio format conversion. """
-    if not input_song == output_song:
-        convert = Converter(input_song, output_song, folder)
-        log.info('Converting {0} to {1}'.format(
-            input_song, output_song.split('.')[-1]))
-        if avconv:
-            exit_code = convert.with_avconv()
-        else:
-            exit_code = convert.with_ffmpeg()
-        return exit_code
-    return 0
+    if input_song == output_song:
+        return 0
+    convert = Converter(input_song, output_song, folder)
+    log.info('Converting {0} to {1}'.format(
+        input_song, output_song.split('.')[-1]))
+    if avconv:
+        exit_code = convert.with_avconv()
+    else:
+        exit_code = convert.with_ffmpeg()
+    return exit_code


 class Converter:
@@ -56,6 +56,8 @@ class Converter:
        _, input_ext = os.path.splitext(self.input_file)
        _, output_ext = os.path.splitext(self.output_file)

+        ffmpeg_params = ''
+
        if input_ext == '.m4a':
            if output_ext == '.mp3':
                ffmpeg_params = '-codec:v copy -codec:a libmp3lame -ar 44100 '
@@ -68,6 +70,9 @@ class Converter:
            elif output_ext == '.m4a':
                ffmpeg_params = '-cutoff 20000 -codec:a libfdk_aac -ar 44100 '

+        if output_ext == '.flac':
+            ffmpeg_params = '-codec:a flac -ar 44100 '
+
        # add common params for any of the above combination
        ffmpeg_params += '-b:a 192k -vn '
        ffmpeg_pre += ' -i'
--- a/core/handle.py
+++ b/core/handle.py
@@ -122,10 +122,11 @@ def get_arguments(raw_args=None, to_group=True, to_merge=True):
        choices={'prompt', 'force', 'skip'})
    parser.add_argument(
        '-i', '--input-ext', default=config['input-ext'],
-        help='prefered input format .m4a or .webm (Opus)')
+        help='prefered input format .m4a or .webm (Opus)',
+        choices={'.m4a', '.webm'})
    parser.add_argument(
        '-o', '--output-ext', default=config['output-ext'],
-        help='prefered output extension .mp3 or .m4a (AAC)')
+        help='prefered output format .mp3, .m4a (AAC), .flac, etc.')
    parser.add_argument(
        '-ff', '--file-format', default=config['file-format'],
        help='File format to save the downloaded song with, each tag '
--- a/core/metadata.py
+++ b/core/metadata.py
@@ -1,7 +1,8 @@
 from mutagen.easyid3 import EasyID3
 from mutagen.id3 import ID3, TORY, TYER, TPUB, APIC, USLT, COMM
 from mutagen.mp4 import MP4, MP4Cover
-from core.const import log
+from mutagen.flac import Picture, FLAC
+from core.const import log, TAG_PRESET, M4A_TAG_PRESET

 import urllib.request

@@ -31,6 +32,9 @@ def embed(music_file, meta_tags):
    elif music_file.endswith('.mp3'):
        log.info('Applying metadata')
        return embed.as_mp3()
+    elif music_file.endswith('.flac'):
+        log.info('Applying metadata')
+        return embed.as_flac()
    else:
        log.warning('Cannot embed metadata into given output extension')
        return False
@@ -50,15 +54,7 @@ class EmbedMetadata:
        # https://github.com/quodlibet/mutagen/blob/master/mutagen/easyid3.py
        # Check out somewhere at end of above linked file
        audiofile = EasyID3(music_file)
-        audiofile['artist'] = meta_tags['artists'][0]['name']
-        audiofile['albumartist'] = meta_tags['artists'][0]['name']
-        audiofile['album'] = meta_tags['album']['name']
-        audiofile['title'] = meta_tags['name']
-        audiofile['tracknumber'] = [meta_tags['track_number'],
-                                    meta_tags['total_tracks']]
-        audiofile['discnumber'] = [meta_tags['disc_number'], 0]
-        audiofile['date'] = meta_tags['release_date']
-        audiofile['originaldate'] = meta_tags['release_date']
+        self._embed_basic_metadata(audiofile, preset=TAG_PRESET)
        audiofile['media'] = meta_tags['type']
        audiofile['author'] = meta_tags['artists'][0]['name']
        audiofile['lyricist'] = meta_tags['artists'][0]['name']
@@ -68,10 +64,6 @@ class EmbedMetadata:
        audiofile['length'] = str(meta_tags['duration'])
        if meta_tags['publisher']:
            audiofile['encodedby'] = meta_tags['publisher']
-        if meta_tags['genre']:
-            audiofile['genre'] = meta_tags['genre']
-        if meta_tags['copyright']:
-            audiofile['copyright'] = meta_tags['copyright']
        if meta_tags['external_ids']['isrc']:
            audiofile['isrc'] = meta_tags['external_ids']['isrc']
        audiofile.save(v2_version=3)
@@ -101,48 +93,13 @@ class EmbedMetadata:
        """ Embed metadata to M4A files. """
        music_file = self.music_file
        meta_tags = self.meta_tags
-        # Apple has specific tags - see mutagen docs -
-        # http://mutagen.readthedocs.io/en/latest/api/mp4.html
-        tags = { 'album'        : '\xa9alb',
-                 'artist'       : '\xa9ART',
-                 'date'         : '\xa9day',
-                 'title'        : '\xa9nam',
-                 'year'         : '\xa9day',
-                 'originaldate' : 'purd',
-                 'comment'      : '\xa9cmt',
-                 'group'        : '\xa9grp',
-                 'writer'       : '\xa9wrt',
-                 'genre'        : '\xa9gen',
-                 'tracknumber'  : 'trkn',
-                 'albumartist'  : 'aART',
-                 'disknumber'   : 'disk',
-                 'cpil'         : 'cpil',
-                 'albumart'     : 'covr',
-                 'copyright'    : 'cprt',
-                 'tempo'        : 'tmpo',
-                 'lyrics'       : '\xa9lyr' }
-
        audiofile = MP4(music_file)
-        audiofile[tags['artist']] = meta_tags['artists'][0]['name']
-        audiofile[tags['albumartist']] = meta_tags['artists'][0]['name']
-        audiofile[tags['album']] = meta_tags['album']['name']
-        audiofile[tags['title']] = meta_tags['name']
-        audiofile[tags['tracknumber']] = [(meta_tags['track_number'],
-                                           meta_tags['total_tracks'])]
-        audiofile[tags['disknumber']] = [(meta_tags['disc_number'], 0)]
-        audiofile[tags['date']] = meta_tags['release_date']
-        audiofile[tags['year']] = meta_tags['year']
-        audiofile[tags['originaldate']] = meta_tags['release_date']
-        audiofile[tags['comment']] = meta_tags['external_urls']['spotify']
-        if meta_tags['genre']:
-            audiofile[tags['genre']] = meta_tags['genre']
-        if meta_tags['copyright']:
-            audiofile[tags['copyright']] = meta_tags['copyright']
-        if meta_tags['lyrics']:
-            audiofile[tags['lyrics']] = meta_tags['lyrics']
+        self._embed_basic_metadata(audiofile, preset=M4A_TAG_PRESET)
+        audiofile[M4A_TAG_PRESET['year']] = meta_tags['year']
+        audiofile[M4A_TAG_PRESET['comment']] = meta_tags['external_urls']['spotify']
        try:
            albumart = urllib.request.urlopen(meta_tags['album']['images'][0]['url'])
-            audiofile[tags['albumart']] = [MP4Cover(
+            audiofile[M4A_TAG_PRESET['albumart']] = [MP4Cover(
                albumart.read(), imageformat=MP4Cover.FORMAT_JPEG)]
            albumart.close()
        except IndexError:
@@ -150,3 +107,47 @@ class EmbedMetadata:

        audiofile.save()
        return True
+
+    def as_flac(self):
+        music_file = self.music_file
+        meta_tags = self.meta_tags
+        audiofile = FLAC(music_file)
+        self._embed_basic_metadata(audiofile)
+        audiofile['year'] = meta_tags['year']
+        audiofile['comment'] = meta_tags['external_urls']['spotify']
+
+        image = Picture()
+        image.type = 3
+        image.desc = 'Cover'
+        image.mime = 'image/jpeg'
+        albumart = urllib.request.urlopen(meta_tags['album']['images'][0]['url'])
+        image.data = albumart.read()
+        albumart.close()
+        audiofile.add_picture(image)
+
+        audiofile.save()
+        return True
+
+    def _embed_basic_metadata(self, audiofile, preset=TAG_PRESET):
+        meta_tags = self.meta_tags
+        audiofile[preset['artist']] = meta_tags['artists'][0]['name']
+        audiofile[preset['albumartist']] = meta_tags['artists'][0]['name']
+        audiofile[preset['album']] = meta_tags['album']['name']
+        audiofile[preset['title']] = meta_tags['name']
+        audiofile[preset['date']] = meta_tags['release_date']
+        audiofile[preset['originaldate']] = meta_tags['release_date']
+        if meta_tags['genre']:
+            audiofile[preset['genre']] = meta_tags['genre']
+        if meta_tags['copyright']:
+            audiofile[preset['copyright']] = meta_tags['copyright']
+        if meta_tags['lyrics']:
+            audiofile[preset['lyrics']] = meta_tags['lyrics']
+        if self.music_file.endswith('.flac'):
+            audiofile[preset['discnumber']] = str(meta_tags['disc_number'])
+        else:
+            audiofile[preset['discnumber']] = [(meta_tags['disc_number'], 0)]
+        if self.music_file.endswith('.flac'):
+            audiofile[preset['tracknumber']] = str(meta_tags['track_number'])
+        else:
+            audiofile[preset['tracknumber']] = [(meta_tags['track_number'],
+                                                 meta_tags['total_tracks'])]