title: How to compare two colors for similarity/difference
body: <p>I want to design a program that can help me assess between 5 pre-defined colors which one is more similar to a variable color, and with what percentage.  The thing is that I don't know how to do that manually step by step. So it is even more difficult to think of a program.</p>
  
  <p>More details: The colors are from photographs of tubes with gel that as different colors. I have 5 tubes with different colors were each is representative of 1 of 5 levels. I want to take photographs of other samples and on the computer assess to which level that sample belongs by comparing colors, and I want to know that with a percentage of approximation too. I would like a program that does something like this: <a href="http://www.colortools.net/color_matcher.html">http://www.colortools.net/color_matcher.html</a></p>
  
  <p>If you can tell me what steps to take, even if they are things for me to think and do manually. It would be very helpful. </p>