title: OpenCV histogram equalization process using cv::equalizeHist():Need help understanding final step for this
body: <p>I've a question regarding Histogram Equalization process using cv::equalizeHist()(a function of OpenCV image processing library). In this website:</p>
  
  <p><a href="http://opencv.willowgarage.com/documentation/cpp/histograms.html#cv-equalizehist" rel="nofollow">Histogram equalization process using opencv explained</a></p>
  
  <p>the histogram equalization process is explained which is:</p>
  
  <ol>
  <li><p>calculate the histogram H for src.</p></li>
  <li><p>normalize the histogram so that the sum of histogram bins is 255.</p></li>
  <li><p>compute the integral of the histogram.
  [equation is given in the above website]</p></li>
  <li><p>transform the image using H' as a look-up table.
  [equation is given in the above website]</p></li>
  </ol>
  
  <p>I'm having problem understanding step number 4. What did the author mean by this line? </p>
  
  <p>Can anyone kindly help me understand how the author got the final equalization result from step number 4?</p>
  
  <p>What method he/she used for step number4? How did he/she transform the image looking at H'?</p>