title: Error when converting IplImage to Mat
body: <pre><code>#include &lt;opencv2/opencv.hpp&gt;
  ...
  
  IplImage* img = cvLoadImage("TestImage.jpg", 1);
  Mat mtx(img);
  </code></pre>
  
  <p>This code should convert the img to Mat format. However, when I implement this I receive an error saying "No matching constructor for initialization of cv::Mat".</p>
  
  <p>Where am I doing wrong? The syntax should be correct so I assume the problem lies somewhere else. I am using OpenCV 3.1.0 and Xcode 7.2.1 in OSX Yosemite.</p>
  
  <p>Thank you in advance</p>