text: '''
  Audio Gstplayer
  ===============
  
  .. versionadded:: 1.8.0
  
  Implementation of a VideoBase with Kivy :class:`~kivy.lib.gstplayer.GstPlayer`
  This player is the prefered player, using Gstreamer 1.0, working on both Python
  2 and 3.
  '''
  
  from kivy.lib.gstplayer import GstPlayer, get_gst_version
  from kivy.core.audio import Sound, SoundLoader
  from kivy.logger import Logger
  from kivy.compat import PY2
  from kivy.clock import Clock
  from os.path import realpath
  
  if PY2:
      from urllib import pathname2url
  else:
      from urllib.request import pathname2url
  
  Logger.info('AudioGstplayer: Using Gstreamer {}'.format(
      '.'.join(map(str, get_gst_version()))))
  
  
  def _on_gstplayer_message(mtype, message):
      if mtype == 'error':
          Logger.error('AudioGstplayer: {}'.format(message))
      elif mtype == 'warning':
          Logger.warning('AudioGstplayer: {}'.format(message))
      elif mtype == 'info':
          Logger.info('AudioGstplayer: {}'.format(message))
  
  
  class SoundGstplayer(Sound):
  
      @staticmethod
      def extensions():
          return ('wav', 'ogg', 'mp3', 'm4a', 'flac')
  
      def __init__(self, **kwargs):
          self.player = None
          super(SoundGstplayer, self).__init__(**kwargs)
  
      def _on_gst_eos_sync(self):
          Clock.schedule_once(self._on_gst_eos, 0)
  
      def _on_gst_eos(self, *dt):
          if self.loop:
              self.player.stop()
              self.player.play()
          else:
              self.stop()
  
      def load(self):
          self.unload()
          uri = self._get_uri()
          self.player = GstPlayer(uri, None, self._on_gst_eos_sync,
                                  _on_gstplayer_message)
          self.player.load()
  
      def play(self):
          # we need to set the volume everytime, it seems that stopping + playing
          # the sound reset the volume.
          self.player.set_volume(self.volume)
          self.player.play()
          super(SoundGstplayer, self).play()
  
      def stop(self):
          self.player.stop()
          super(SoundGstplayer, self).stop()
  
      def unload(self):
          if self.player:
              self.player.unload()
              self.player = None
  
      def seek(self, position):
          self.player.seek(position / self.length)
  
      def get_pos(self):
          return self.player.get_position()
  
      def _get_length(self):
          return self.player.get_duration()
  
      def on_volume(self, instance, volume):
          self.player.set_volume(volume)
  
      def _get_uri(self):
          uri = self.filename
          if not uri:
              return
          if not '://' in uri:
              uri = 'file:' + pathname2url(realpath(uri))
          return uri
  
  SoundLoader.register(SoundGstplayer)
  