Added zerocopy, improved stream robustness and reduced latency

stream-gst.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+import sys
+import gi
+gi.require_version('Gst', '1.0')
+from gi.repository import Gst, GLib
+from datetime import datetime
+
+Gst.init(None)
+
+device = sys.argv[1] if len(sys.argv) > 1 else "/dev/video0"
+port = sys.argv[2] if len(sys.argv) > 2 else "5000"
+
+pipeline = Gst.parse_launch(f"""
+    v4l2src device={device} io-mode=2 !
+    videoconvert !
+    textoverlay name=overlay halignment=left valignment=top font-desc="Monospace 36" !
+    x265enc tune=zerolatency speed-preset=ultrafast option-string="bframes=0:keyint=30:scenecut=0" !
+    h265parse config-interval=1 !
+    rtph265pay config-interval=1 mtu=1400 !
+    udpsink host=127.0.0.1 port={port} sync=false async=false
+""")
+
+overlay = pipeline.get_by_name("overlay")
+
+def update_text():
+    overlay.set_property("text", datetime.now().strftime("%H:%M:%S.%f")[:-3])
+    return True
+
+GLib.timeout_add(5, update_text)
+
+pipeline.set_state(Gst.State.PLAYING)
+loop = GLib.MainLoop()
+try:
+    loop.run()
+except KeyboardInterrupt:
+    pipeline.set_state(Gst.State.NULL)