Split conversion code

core/convert.py

@@ -0,0 +1,75 @@
+import subprocess
+import os
+
+def song(input_song, output_song, avconv, verbose):
+    if not input_song == output_song:
+        input_song = input_song.encode('utf-8')
+        output_song = output_song.encode('utf-8')
+        print('Converting ' + input_song + ' to ' + output_song.split('.')[-1])
+        if avconv:
+            convert_with_avconv(input_song, output_song, verbose)
+        else:
+            convert_with_FFmpeg(input_song, output_song, verbose)
+        os.remove('Music/' + input_song)
+
+def convert_with_avconv(input_song, output_song, verbose):
+    # different path for windows
+    if os.name == 'nt':
+        avconv_path = 'Scripts\\avconv.exe'
+    else:
+        avconv_path = 'avconv'
+
+    if verbose:
+        level = 'debug'
+    else:
+        level = '0'
+
+    command = [avconv_path,
+               '-loglevel', level,
+               '-i',        'Music/' + input_song,
+               '-ab',       '192k',
+               'Music/' + output_song]
+
+    subprocess.call(command)
+
+
+def convert_with_FFmpeg(input_song, output_song, verbose):
+    # What are the differences and similarities between ffmpeg, libav, and avconv?
+    # https://stackoverflow.com/questions/9477115
+    # ffmeg encoders high to lower quality
+    # libopus > libvorbis >= libfdk_aac > aac > libmp3lame
+    # libfdk_aac due to copyrights needs to be compiled by end user
+    # on MacOS brew install ffmpeg --with-fdk-aac will do just that. Other OS?
+    # https://trac.ffmpeg.org/wiki/Encode/AAC
+
+    if os.name == "nt":
+        ffmpeg_pre = 'Scripts\\ffmpeg.exe '
+    else:
+        ffmpeg_pre = 'ffmpeg '
+
+    ffmpeg_pre += '-y '
+    if not verbose:
+        ffmpeg_pre += '-hide_banner -nostats -v panic '
+
+    input_ext = input_song.split('.')[-1]
+    output_ext = output_song.split('.')[-1]
+
+    if input_ext == 'm4a':
+        if output_ext == 'mp3':
+            ffmpeg_params = '-codec:v copy -codec:a libmp3lame -q:a 2 '
+        elif output_ext == 'webm':
+            ffmpeg_params = '-c:a libopus -vbr on -b:a 192k -vn '
+
+    elif input_ext == 'webm':
+        if output_ext == 'mp3':
+            ffmpeg_params = ' -ab 192k -ar 44100 -vn '
+        elif output_ext == 'm4a':
+            ffmpeg_params = '-cutoff 20000 -c:a libfdk_aac -b:a 192k -vn '
+
+    command = (ffmpeg_pre +
+              '-i Music/' + input_song + ' ' +
+               ffmpeg_params +
+              'Music/' + output_song + '').split(' ')
+
+    subprocess.call(command)
+