share/gpodder/extensions/mp3gain.py

   1 # -*- coding: utf-8 -*-
   2 # This extension adjusts mp3s so that they all have the same volume
   3 #
   4 # Requires: mp3gain
   5 #
   6 # (c) 2011-11-06 Bernd Schlapsi <brot@gmx.info>
   7 # Released under the same license terms as gPodder itself.
   8
   9 import os
  10 import subprocess
  11
  12 import gpodder
  13 from gpodder import util
  14
  15 import logging
  16 logger = logging.getLogger(__name__)
  17
  18 _ = gpodder.gettext
  19
  20 __title__ = _('mp3gain Volume Normalizer')
  21 __description__ = _('Normalize the volume of MP3 files without re-encoding')
  22 __author__ = 'Bernd Schlapsi <brot@gmx.info>'
  23
  24
  25 DefaultConfig = {
  26     'context_menu': True,
  27 }
  28
  29
  30 class gPodderExtension:
  31     MIME_TYPE = 'audio/mpeg'
  32
  33     def __init__(self, container):
  34         self.container = container
  35         self.config = self.container.config
  36
  37         self.mp3gain = self.container.require_command('mp3gain')
  38
  39     def on_episode_downloaded(self, episode):
  40         self._convert_episode(episode)
  41
  42     def on_episodes_context_menu(self, episodes):
  43         if not self.config.context_menu:
  44             return None
  45
  46         if not all(e.was_downloaded(and_exists=True) for e in episodes):
  47             return None
  48
  49         if not any(e.mime_type == self.MIME_TYPE for e in episodes):
  50             return None
  51
  52         return [(_('Normalize volume (mp3gain)'), self._convert_episodes)]
  53
  54     def _convert_episode(self, episode):
  55         if episode.mime_type != self.MIME_TYPE:
  56             return
  57
  58         filename = episode.local_filename(create=False)
  59         if filename is None:
  60             return
  61
  62         cmd = [self.mp3gain, '-c', filename]
  63
  64         p = subprocess.Popen(cmd, stdout=subprocess.PIPE,
  65                 stderr=subprocess.PIPE)
  66         stdout, stderr = p.communicate()
  67
  68         if p.returncode == 0:
  69             logger.info('mp3gain processing successful.')
  70         else:
  71             logger.warn('mp3gain failed: %s / %s', stdout, stderr)
  72
  73     def _convert_episodes(self, episodes):
  74         for episode in episodes:
  75             self._convert_episode(episode)
  76