title: Problem determining Color Saturation
body: <p>I am writing a tool that will attempt to determine which of the <a href="http://en.wikipedia.org/wiki/X11_color_names" rel="nofollow">known colors</a> is "closest" to some user-chosen color (from the full RGB gamut). I am noticing that the values returned by Microsoft's GetHue and GetBrightness appear to have the same values as the HSL Hue and the HSL Lightness values computed by the <a href="http://en.wikipedia.org/wiki/HSL_and_HSV" rel="nofollow">HSL and HSV</a> article. But Microsoft's GetSaturation does not appear to consistently equate to any computed value (HSL, HSV, HSI).</p>
  
  <p>Question(s) </p>
  
  <ol>
  <li>What color model does Microsoft use for its GetHue, GetSaturation, and GetBrightness functions? </li>
  <li>Has anyone found errors in the <a href="http://en.wikipedia.org/wiki/HSL_and_HSV" rel="nofollow">HSL and HSV</a> computations?</li>
  </ol>