Source Code for Module timeside.encoder.mp3

  1  # -*- coding: utf-8 -*- 
  2  # 
  3  # Copyright (C) 2007-2012 Parisson SARL 
  4  # Copyright (c) 2006-2012 Guillaume Pellerin <pellerin@parisson.com> 
  5  # Copyright (c) 2010-2012 Paul Brossier <piem@piem.org> 
  6  # Copyright (c) 2009-2010 Olivier Guilyardi <olivier@samalyse.com> 
  7   
  8   
  9  # This file is part of TimeSide. 
 10   
 11  # TimeSide is free software: you can redistribute it and/or modify 
 12  # it under the terms of the GNU General Public License as published by 
 13  # the Free Software Foundation, either version 2 of the License, or 
 14  # (at your option) any later version. 
 15   
 16  # TimeSide is distributed in the hope that it will be useful, 
 17  # but WITHOUT ANY WARRANTY; without even the implied warranty of 
 18  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 19  # GNU General Public License for more details. 
 20   
 21  # You should have received a copy of the GNU General Public License 
 22  # along with TimeSide.  If not, see <http://www.gnu.org/licenses/>. 
 23   
 24  # Authors: Guillaume Pellerin <yomguy@parisson.com> 
 25  #          Paul Brossier <piem@piem.org> 
 26   
 27  from timeside.core import implements, interfacedoc 
 28  from timeside.encoder.core import GstEncoder 
 29  from timeside.api import IEncoder 
 30  from timeside.tools import * 
 31   
 32  import mutagen 
 33   
 34 -class Mp3Encoder(GstEncoder): 
 35      """ gstreamer-based mp3 encoder """ 
 36      implements(IEncoder) 
 37   
 38      @interfacedoc 
 39 -    def setup(self, channels=None, samplerate=None, blocksize=None, totalframes=None): 
 40          super(Mp3Encoder, self).setup(channels, samplerate, blocksize, totalframes) 
 41   
 42          self.pipe = '''appsrc name=src 
 43                    ! audioconvert 
 44                    ! lamemp3enc target=quality quality=2 encoding-engine-quality=standard 
 45                    ! xingmux 
 46                    ! id3v2mux 
 47                    ''' 
 48   
 49          if self.filename and self.streaming: 
 50              self.pipe += ''' ! tee name=t 
 51              ! queue ! filesink location=%s 
 52              t. ! queue ! appsink name=app sync=False 
 53              ''' % self.filename 
 54   
 55          elif self.filename : 
 56              self.pipe += '! filesink location=%s async=False sync=False ' % self.filename 
 57          else: 
 58              self.pipe += '! queue ! appsink name=app sync=False ' 
 59   
 60          self.start_pipeline(channels, samplerate) 
 61   
 62      @staticmethod 
 63      @interfacedoc 
 64 -    def id(): 
 65          return "gst_mp3_enc" 
 66   
 67      @staticmethod 
 68      @interfacedoc 
 69 -    def description(): 
 70          return "MP3 GStreamer based encoder" 
 71   
 72      @staticmethod 
 73      @interfacedoc 
 74 -    def format(): 
 75          return "MP3" 
 76   
 77      @staticmethod 
 78      @interfacedoc 
 79 -    def file_extension(): 
 80          return "mp3" 
 81   
 82      @staticmethod 
 83      @interfacedoc 
 84 -    def mime_type(): 
 85          return "audio/mpeg" 
 86   
 87      @interfacedoc 
 88 -    def set_metadata(self, metadata): 
 89          self.metadata = metadata 
 90   
 91 -    def write_metadata(self): 
 92          """Write all ID3v2.4 tags to file from self.metadata""" 
 93          from mutagen import id3 
 94          id3 = id3.ID3(self.filename) 
 95          for tag in self.metadata.keys(): 
 96              value = self.metadata[tag] 
 97              frame = mutagen.id3.Frames[tag](3,value) 
 98              try: 
 99                  id3.add(frame) 
100              except: 
101                  raise IOError('EncoderError: cannot tag "'+tag+'"') 
102          try: 
103              id3.save() 
104          except: 
105              raise IOError('EncoderError: cannot write tags') 
106