subprojects/gst-python/old_examples/maemogst.py

   1 import gobject
   2 gobject.threads_init()
   3 import gtk
   4 gtk.gdk.threads_init()
   5 import hildon
   6 import gst
   7 import sys
   8
   9 # VideoWidget taken from play.py in gst-python examples
  10 class VideoWidget(gtk.DrawingArea):
  11     def __init__(self):
  12         gtk.DrawingArea.__init__(self)
  13         self.imagesink = None
  14         self.unset_flags(gtk.DOUBLE_BUFFERED)
  15
  16     def do_expose_event(self, event):
  17         if self.imagesink:
  18             self.imagesink.expose()
  19             return False
  20         else:
  21             return True
  22
  23     def set_sink(self, sink):
  24         assert self.window.xid
  25         self.imagesink = sink
  26         self.imagesink.set_xwindow_id(self.window.xid)
  27
  28 class MaemoGstView:
  29
  30     def __init__(self):
  31         # hildon has one program instance per app, so get instance
  32         self.p = hildon.Program.get_instance()
  33         # set name of application: this shows in titlebar
  34         gtk.set_application_name("Maemo GStreamer VideoTest")
  35         # stackable window in case we want more windows in future in app
  36         self.w = hildon.StackableWindow()
  37         box = gtk.VBox()
  38         self.video_widget = VideoWidget()
  39         # video widget we want to expand to size
  40         box.pack_start(self.video_widget, True, True, 0)
  41         # a button finger height to play/pause
  42         self.button = hildon.Button(gtk.HILDON_SIZE_FINGER_HEIGHT,
  43             hildon.BUTTON_ARRANGEMENT_VERTICAL, title="Pause")
  44         self.button.connect_after("clicked", self.on_button_clicked)
  45         # don't want button to expand or fill, just stay finger height
  46         box.pack_start(self.button, False, False, 0)
  47         self.w.add(box)
  48         self.w.connect("delete-event", gtk.main_quit)
  49         self.p.add_window(self.w)
  50         self.w.show_all()
  51         self.start_streaming()
  52
  53     def start_streaming(self):
  54         # we use ximagesink solely for screenshotting ability
  55         # less cpu usage would happen with videotestsrc ! xvimagesink
  56         self.pipeline = \
  57             gst.parse_launch("videotestsrc ! videoscale ! ximagesink")
  58         bus = self.pipeline.get_bus()
  59         # need to connect to sync message handler so we get the sink to be
  60         # embedded at the right time and not have a temporary new window
  61         bus.enable_sync_message_emission()
  62         bus.add_signal_watch()
  63         bus.connect("sync-message::element", self.on_sync_message)
  64         bus.connect("message", self.on_message)
  65         self.pipeline.set_state(gst.STATE_PLAYING)
  66
  67     def on_sync_message(self, bus, message):
  68         if message.structure is None:
  69             return
  70         if message.structure.get_name() == 'prepare-xwindow-id':
  71             # all this is needed to sync with the X server before giving the
  72             # x id to the sink
  73             gtk.gdk.threads_enter()
  74             gtk.gdk.display_get_default().sync()
  75             self.video_widget.set_sink(message.src)
  76             message.src.set_property("force-aspect-ratio", True)
  77             gtk.gdk.threads_leave()
  78
  79     def on_message(self, bus, message):
  80         if message.type == gst.MESSAGE_ERROR:
  81             err, debug = message.parse_error()
  82             hildon.hildon_banner_show_information(self.w, '',
  83                 "Error: %s" % err)
  84
  85     def on_button_clicked(self, widget):
  86         success, state, pending = self.pipeline.get_state(1)
  87         # do not listen if in middle of state change
  88         if not pending:
  89             if state == gst.STATE_PLAYING:
  90                 self.pipeline.set_state(gst.STATE_PAUSED)
  91                 self.button.set_label("Play")
  92             else:
  93                 self.pipeline.set_state(gst.STATE_PLAYING)
  94                 self.button.set_label("Pause")
  95
  96 def main():
  97     view = MaemoGstView()
  98     gtk.main()
  99
 100 if __name__ == '__main__':
 101     sys.exit(main())