added capture_device_index support

raspberry-pi/sensors/opticalSensor.py

@@ -110,7 +110,12 @@ class OpticalSensor():
       self._t.start()
 
   def _getFrames(self):
-    self.cap = cv2.VideoCapture(self.conf["opt_sensor"]["capture_device"])
+    try:
+      dev = int(self.conf["opt_sensor"]["capture_device"])
+    except ValueError:
+      dev = self.conf["opt_sensor"]["capture_device"]
+    self.cap = cv2.VideoCapture(dev)
+
     while self.running:
       self.success, image = self.cap.read()
       if self.success: