#!/usr/bin/env python # decodebin.py - Audio autopluging example using 'decodebin' element # Copyright (C) 2006 Jason Gerard DeRose <jderose@jasonderose.org> # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Library General Public # License as published by the Free Software Foundation; either # version 2 of the License, or (at your option) any later version. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Library General Public License for more details. # # You should have received a copy of the GNU Library General Public # License along with this library; if not, write to the # Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, # Boston, MA 02110-1301, USA. import sys import gobject gobject.threads_init() import pygst pygst.require('0.10') import gst class Decodebin: def __init__(self, location): # The pipeline self.pipeline = gst.Pipeline() # Create bus and connect several handlers self.bus = self.pipeline.get_bus() self.bus.add_signal_watch() self.bus.connect('message::eos', self.on_eos) self.bus.connect('message::tag', self.on_tag) self.bus.connect('message::error', self.on_error) # Create elements self.src = gst.element_factory_make('filesrc') self.dec = gst.element_factory_make('decodebin') self.conv = gst.element_factory_make('audioconvert') self.rsmpl = gst.element_factory_make('audioresample') self.sink = gst.element_factory_make('alsasink') # Set 'location' property on filesrc self.src.set_property('location', location) # Connect handler for 'new-decoded-pad' signal self.dec.connect('new-decoded-pad', self.on_new_decoded_pad) # Add elements to pipeline self.pipeline.add(self.src, self.dec, self.conv, self.rsmpl, self.sink) # Link *some* elements # This is completed in self.on_new_decoded_pad() self.src.link(self.dec) gst.element_link_many(self.conv, self.rsmpl, self.sink) # Reference used in self.on_new_decoded_pad() self.apad = self.conv.get_pad('sink') # The MainLoop self.mainloop = gobject.MainLoop() # And off we go! self.pipeline.set_state(gst.STATE_PLAYING) self.mainloop.run() def on_new_decoded_pad(self, element, pad, last): caps = pad.get_caps() name = caps[0].get_name() print 'on_new_decoded_pad:', name if name == 'audio/x-raw-float' or name == 'audio/x-raw-int': if not self.apad.is_linked(): # Only link once pad.link(self.apad) def on_eos(self, bus, msg): print 'on_eos' self.mainloop.quit() def on_tag(self, bus, msg): taglist = msg.parse_tag() print 'on_tag:' for key in taglist.keys(): print '\t%s = %s' % (key, taglist[key]) def on_error(self, bus, msg): error = msg.parse_error() print 'on_error:', error[1] self.mainloop.quit() if __name__ == '__main__': if len(sys.argv) == 2: Decodebin(sys.argv[1]) else: print 'Usage: %s /path/to/media/file' % sys.argv[0]