add cv2 video stream

camera/video_client_pi_cv2.py

 # Make a file-like object out of the connection
 connection = client_socket.makefile('wb')
 try:
-    cap = cv2.
-    with picamera.PiCamera() as camera:
-        camera.resolution = (640, 480)
-        # Start a preview and let the camera warm up for 2 seconds
-        camera.start_preview()
-        time.sleep(2)
+    cap = cv2.VideoCapture("run.mp4")
 
-        # Note the start time and construct a stream to hold image data
-        # temporarily (we could write it directly to connection but in this
-        # case we want to find out the size of each capture first to keep
-        # our protocol simple)
-        start = time.time()
-        stream = io.BytesIO()
-        for foo in camera.capture_continuous(stream, 'jpeg'):
-            # Write the length of the capture to the stream and flush to
-            # ensure it actually gets sent
-            connection.write(struct.pack('<L', stream.tell()))
-            connection.flush()
-            # Rewind the stream and send the image data over the wire
-            stream.seek(0)
-            connection.write(stream.read())
-            # If we've been capturing for more than 30 seconds, quit
-            if time.time() - start > 30:
-                break
-            # Reset the stream for the next capture
-            stream.seek(0)
-            stream.truncate()
+    while True:
+        ret, frame = cap.read()
+
+        if frame == None:
+            break
+        
+        image = cv2.imencode('.jpg', frame)
+        stream = image.tobytes()
+
+        # Write the length of the capture to the stream and flush to
+        # ensure it actually gets sent
+        connection.write(struct.pack('<L', stream.tell()))
+        connection.flush()
+        # Rewind the stream and send the image data over the wire
+        stream.seek(0)
+        connection.write(stream.read())
+        # If we've been capturing for more than 30 seconds, quit
+        if time.time() - start > 30:
+            break
+        # Reset the stream for the next capture
+        stream.seek(0)
+        stream.truncate()
     # Write a length of zero to the stream to signal we're done
     connection.write(struct.pack('<L', 0))
 finally: