Set a lower log level when list cameras

trackmultiplefaces.py

@@ -59,6 +59,9 @@ SUSPICIOUS_THRESHOLD = 2
 
 # Get the number of cameras available
 def list_available_cameras():
+    loglevel = cv2.getLogLevel()
+    cv2.setLogLevel(2)
+
     cameras = []
     for i in range(10):
         temp_camera = cv2.VideoCapture(i)
@@ -66,6 +69,7 @@ def list_available_cameras():
             temp_camera.release()
             cameras.append(i)
 
+    cv2.setLogLevel(loglevel)
     print("Found cameras:", cameras)
     return cameras