title: How to read an image as double in OpenCV?
body: <p>I want to implement a similar function as shown below using the opencv.</p>
  
  <pre><code>image=double(imread('mask.jpg'));
  </code></pre>
  
  <p>I have implemented something like this.How to convert this into double.</p>
  
  <pre><code>cv::Mat image= imread(arg[1]);
  </code></pre>
  
  <p>where <code>arg[1]</code> contains my image which is to be stored in <code>Mat</code> image as double. How to implement this.</p>