title: checking the Colors Opencv Python
body: <p>I have a code to detect two colors green and blue. I want to check if
  green color is detected to print a massage and if blue color is detected to print another message too</p>
  <p>Here is the Code:</p>
  <pre><code>import cv2
  
  import numpy as np
  
  cap = cv2.VideoCapture(0)
  
  while(1):
  
      # Take each frame
      _, frame = cap.read()
  
      # Convert BGR to HSV
      hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)
  
      # define range of blue color in HSV
      lower_blue = np.array([110,50,50])
      upper_blue = np.array([130,255,255])
  
      lower_green = np.array([50, 50, 120])
      upper_green = np.array([70, 255, 255])
      green_mask = cv2.inRange(hsv, lower_green, upper_green) # I have the Green threshold image.
  
      # Threshold the HSV image to get only blue colors
      blue_mask = cv2.inRange(hsv, lower_blue, upper_blue)
      mask = blue_mask + green_mask
  ############this is the Error ####################
      if mask==green_mask:
          print &quot;DOne&quot;
  ################################################
  
      # Bitwise-AND mask and original image
      res = cv2.bitwise_and(frame,frame, mask= mask)
  
      cv2.imshow('frame',frame)
      cv2.imshow('mask',mask)
      cv2.imshow('res',res)
      k = cv2.waitKey(5) &amp; 0xFF
      if k == 27:
          break
  
  cv2.destroyAllWindows()
  </code></pre>
  <p>Running the above code gives me following error:</p>
  <blockquote>
  <p>if mask==green_mask:</p>
  <p>ValueError: The truth value of an array with more
  than one element is ambiguous. Use a.any() or a.all()</p>
  </blockquote>
  <p>Any ideas how to fix this?</p>