title: how to capture a video with four channels (RGB-IR) in open cv?
body: <p>Does anybody know how to use four channels in open cv. I have this rgb-ir camera from e con systems (See3CAM_CU40) and I tried to write the code like below in the usual way. It gives just a complete black video. I guess this is because opencv is originally asking for gbr. But I don't know what to do when the video feed has 4 channels.</p>
  
  <pre><code>import cv2
  def main():
  
       windowName1 =" LIve video Feed"
  
       cv2.namedWindow(windowName1)
  
       cap=cv2.VideoCapture(1) 
       # cap.set(cv2.CAP_PROP_EXPOSURE,-1)
       cap.set(cv2.CAP_FFMPEG,True)
       cap.set(cv2.CAP_PROP_FPS,30)
  
       if cap.isOpened():
           ret,frame = cap.read()
  
       else:
           ret=False
       while ret:
           ret,frame =cap.read()
      #     r,g,b =cv2.split(frame)
      #     output = cv2.cvtColor(frame,cv2.COLOR_BGR2GRAY)
  
  
           cv2.imshow(windowName1,frame)
           if cv2.waitKey(1) ==27:
               break
  
       #cv2.destroyWindow(windowName)
       cv2.destroyAllWindows()
  
  
       cap.release()
  
  if __name__ == '__main__':
      main()
  </code></pre>