title: How detect different colors
body: <p>I am learning Image Filtering using opencv. I wrote some code but my code could only detect objects with red color, How can I detect objects with other colors.</p>
  
  <p>I tried different numpy array values, still I'm not satisfied with output</p>
  
  <pre><code>hsv = cv2.cvtColor(frame,cv2.COLOR_BGR2HSV)
  
  lower_blue = np.array([150,150,0])
  upper_blue = np.array([255,255,225])
  
  mask = cv2.inRange(hsv,lower_blue,upper_blue)
  res = cv2.bitwise_and(frame,frame,mask=mask)
  cv2.imshow('res',res)
  </code></pre>