title: Edge with threshold bar
body: <p>I am currently creating a program which manipulates and changes pixel values within black and white images. I am using Microsoft Visual Studio 2010.</p>
  
  <p>So far i have created edge detection using roberts gradient, 
  Firstly i created this without a track bar for changing the level of the threshold.</p>
  
  <p>When i added in the track bar to change the threshold value the original image would disappear off screen. the idea was to have both the original image and the processed image side by side.</p>