title: Drawing a videostream using wxWidgets
body: <p>I have a relatively simple application which currently utilizes OpenCV to grab an image from a camera using <code>cv::VideoCapture</code> and view the resulting image in a window using <code>imshow()</code> running on OS X El Capitan.</p>
  
  <p>In between I'm doing some basic image modification but this is not crucial to my problem.</p>
  
  <p>Since the GUI implemented by OpenCV is pretty basic I decided to redo it using wxWidgets. I got it basically running similarly to the implementation <a href="http://larryo.org/work/information/wxopencv/" rel="nofollow">linked</a> in the tutorial section of wxWidgets. (Updated it to C++11 etc. but the idea is pretty much identical. Code is located on <a href="https://github.com/heinemml/wxOpenCV" rel="nofollow">github</a>.)</p>
  
  <p>Now heres my problem: In best cases I get half the framerate as I get with the OpenCV only solution. OpenCV uses qt underneath. But when I look into the stack trace it comes down to similar function calls using CoreGraphics. </p>
  
  <p>So my question boils down to: What is the best way do draw an image to a window with a framerate > 20fps using wxWidgets on OS X? Currently I use the DrawBitmap() function.</p>
  
  <p>Bonus question: when I have the window on my Macbooks internal Retina screen the framerate gets even worse. Is there maybe any preprocessing/scaling on the picture I should do to take off load from the GUI-process?</p>