add RTSP example

code/Python/opencv/capture.py

@@ -0,0 +1,24 @@
+#!/usr/bin/env python3
+
+import cv2
+
+RTSP_ADDR = 'rtsp://localhost:8554/cam'
+DEVICE_ADDR = 2
+
+cam = cv2.VideoCapture(DEVICE_ADDR)
+
+while True:
+    result, image = cam.read()
+
+    cv2.imshow('Camera', image)
+
+    if cv2.waitKey(1) & 0xFF == ord('s'):
+        cv2.imwrite('capture.png', image)
+
+    if cv2.waitKey(1) & 0xFF == ord('q'):
+        break
+
+cam.release()
+
+cv2.destroyWindow('Camera')
+cv2.destroyAllWindows()