#!/usr/bin/env python # Attempting to dynamically switch between input sources # GdkX11 to get access to xid, GstVideo to get access to set_window_handle import gi, signal gi.require_version('Gtk', '3.0') gi.require_version('Gst', '1.0') gi.require_version('GstVideo', '1.0') from gi.repository import Gtk, Gst, GdkX11, GstVideo class Main: def __init__(self): # Create gui bits and bobs self.mainwindow = Gtk.Builder() self.mainwindow.add_from_file("example4.glade") signals = { "on_input1_clicked" : self.SetInput1, "on_input2_clicked" : self.SetInput2, "on_quit_clicked" : self.OnQuit, } self.mainwindow.connect_signals(signals) # Create GStreamer bits and bobs # Initiate Gstreamer Gst.init(None) # Some capabilities we want to share between different elements commoncaps = Gst.Caps.from_string("video/x-raw,width=1280,height=720,framerate=30/1") # Set up the pipeline self.pipeline = Gst.Pipeline() # Add a videotestsrc element, set it to pattern "ball" and some other properties self.ball = Gst.ElementFactory.make("videotestsrc", "ball") self.ball.set_property("pattern", "ball") #self.ball.set_property("flip", True) # Add a capsfilter that we want to apply to our ball self.ballcaps = Gst.ElementFactory.make("capsfilter", "ballcaps") self.ballcaps.set_property("caps", commoncaps) # Webcam source self.webcam = Gst.ElementFactory.make("v4l2src", "webcam") self.webcam.set_property("device", "/dev/video0") # Webcam capsfilter self.webcamcaps = Gst.ElementFactory.make("capsfilter", "webcamcaps") self.webcamcaps.set_property("caps", commoncaps) # Add a videosink (where the playback happens) self.videosink = Gst.ElementFactory.make("autovideosink", "videosink") self.videosink.set_property("sync", False) # Add initial elements to the pipeline self.pipeline.add(self.ball) self.pipeline.add(self.ballcaps) self.pipeline.add(self.videosink) # Link the initial pipeline self.ball.link(self.ballcaps) self.ballcaps.link(self.videosink) # Set up a bus to our pipeline to get notified when the video is ready self.bus = self.pipeline.get_bus() self.bus.enable_sync_message_emission() self.bus.connect("sync-message::element", self.OnSyncElement) # Summon the window and connect the window's close button to quit self.window = self.mainwindow.get_object("mainwindow") self.window.connect("delete-event", Gtk.main_quit) self.window.show_all() # Get window ID of the viewport widget from the GUI self.win_id = self.mainwindow.get_object("viewport").get_window().get_xid() # Play! self.pipeline.set_state(Gst.State.PLAYING) # When we get a message that video is ready to display, set the # correct window id to hook it to our viewport def OnSyncElement(self, bus, message): if message.get_structure().get_name() == "prepare-window-handle": print("prepare-window-handle") message.src.set_window_handle(self.win_id) def SetInput1(self, widget): print("Switch to input 1") # Halt current pipeline and tear it down self.pipeline.set_state(Gst.State.READY) self.webcamcaps.unlink(self.videosink) self.pipeline.remove(self.webcam) self.pipeline.remove(self.webcamcaps) # Construct new pipeline self.pipeline.add(self.ball) self.pipeline.add(self.ballcaps) self.ball.link(self.ballcaps) self.ballcaps.link(self.videosink) self.pipeline.set_state(Gst.State.PLAYING) def SetInput2(self, widget): print("Switch to input 2") # Halt current pipeline and tear it down self.pipeline.set_state(Gst.State.READY) self.ballcaps.unlink(self.videosink) self.pipeline.remove(self.ball) self.pipeline.remove(self.ballcaps) # Construct new pipeline self.pipeline.add(self.webcam) self.pipeline.add(self.webcamcaps) self.webcam.link(self.webcamcaps) self.webcamcaps.link(self.videosink) self.pipeline.set_state(Gst.State.PLAYING) def OnQuit(self, widget): print("quit") Gtk.main_quit() # Workaround to get Ctrl+C to terminate from command line # ref: https://bugzilla.gnome.org/show_bug.cgi?id=622084#c12 signal.signal(signal.SIGINT, signal.SIG_DFL) start = Main() Gtk.main()