OpenCV error. Version : 2.4.11

[KathiravanNatarajan]

OpenCV Error: Assertion failed (scn == 3 || scn == 4) in cvtColor, file /home/travis/miniconda/conda-bld/work/opencv-2.4.11/modules/imgproc/src/color.cpp, line 3739
Traceback (most recent call last):
File "testImplementation.py", line 206, in
GestureDemo().run()
File "testImplementation.py", line 200, in run
super(GestureDemo, self).run()
File "/home/kathirdrone/Desktop/ARDRONE /GestureDetection/GestureDetection/current_src/eventBasedAnimationClass.py", line 47, in run
self.onTimerFiredWrapper()
File "/home/kathirdrone/Desktop/ARDRONE /GestureDetection/GestureDetection/current_src/eventBasedAnimationClass.py", line 30, in onTimerFiredWrapper
self.onTimerFired()
File "testImplementation.py", line 125, in onTimerFired
self.gp.process()
File "/home/kathirdrone/Desktop/ARDRONE /GestureDetection/GestureDetection/current_src/GesturesApi.py", line 297, in process
self.threshold()
File "/home/kathirdrone/Desktop/ARDRONE /GestureDetection/GestureDetection/current_src/GesturesApi.py", line 111, in threshold
grey = cv2.cvtColor(self.original, cv2.COLOR_BGR2GRAY)
cv2.error: /home/travis/miniconda/conda-bld/work/opencv-2.4.11/modules/imgproc/src/color.cpp:3739: error: (-215) scn == 3 || scn == 4 in function cvtColor

[VasuAgrawal]

Can you give me some more information on your setup, in order for me to try to replicate this error?

[KathiravanNatarajan]

Yeah. I found the error, Since I was using virtualBox I couldn't connect my webcam with the guest OS. Thanks for the reply.