title: Correct my code please and tell me what i am doing wrong in it?
body: <pre class="lang-py prettyprint-override"><code>import cv2
  image = cv2.imread(&quot;palm.jpg&quot;)
  cv2.imshow(&quot;palm&quot;, image)
  cv2.waitKey(0)
  gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
  </code></pre>
  <p>Error in my screen:</p>
  <blockquote>
  <p>cv2.imshow(&quot;palm&quot;, image)</p>
  <p>cv2.error: OpenCV(4.1.0) C:\projects\opencv-python\opencv\modules\highgui\src\window.cpp:352: error: (-215:Assertion failed) size.width&gt;0 &amp;&amp; size.height&gt;0 in function 'cv::imshow'</p>
  </blockquote>