title: Access a pixel of Mat in OpenCV
body: <p>I want to access to a pixel in OpenCV, in an image of type Mat.</p>
  
  <p>Let's say I do:</p>
  
  <pre><code>Mat image;
  </code></pre>
  
  <p>I want to access to the pixel 30, 50 in the image.</p>
  
  <p>I tried to do <code>image[30][50]</code>, but it did not work.</p>
  
  <p>Any ideas? Thanks a lot!!!</p>