support reading and publishing with Media-over-QUIC (#5815)

Media-over-QUIC is a streaming protocol built upon cutting edge
protocols (QUIC, HTTP3) and browser APIs (WebTransport, WebCodecs).
It's slightly faster than WebRTC, has an advanced data recovery
mechanism (placed at the frame level and not at the packet level), it
supports additional codecs (FLAC) and is less complicated to route.

docs/4-read/12-python-opencv.md

@@ -0,0 +1,24 @@
+# Python and OpenCV
+
+Python-based software can read streams from the server with the OpenCV library, acting as a [RTSP client](04-rtsp.md).
+
+```python
+import cv2
+
+cap = cv2.VideoCapture('rtsp://localhost:8554/mystream')
+if not cap.isOpened():
+    raise Exception("can't open video capture")
+
+while True:
+    ret, frame = cap.read()
+    if not ret:
+        raise Exception("can't receive frame")
+
+    cv2.imshow('frame', frame)
+
+    if cv2.waitKey(1) == ord('q'):
+        break
+
+cap.release()
+cv2.destroyAllWindows()
+```