title: How to use imageSearch with transparent image?
body: <p>I'm trying to find a transparent image on the screen. But it can't find the picture because its edges are transparent. Is there any solution method? it may like a library or win api. Maybe my use is wrong.</p>
  
  <p>Used image file:<a href="https://i.stack.imgur.com/PiMkJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PiMkJ.png" alt="http://pngimg.com/uploads/light/light_PNG14440.png"></a></p>
  
  <pre><code>CoordMode, Pixel, Screen
  ImageSearch, FoundX, FoundY, 0,0, A_ScreenWidth, A_ScreenHeight,*50 *TransBlack C:\Users\PC\Desktop\light_PNG14440.png
  if (ErrorLevel = 2)
       MsgBox Could not conduct the search.
  else if (ErrorLevel = 1)
  MsgBox Icon could not be found on the screen.
  else
  MsgBox The icon was found at %FoundX%x%FoundY%.
  </code></pre>
  
  <p>I expect the output to be <code>The icon was found at 100x100.</code>, but the actual output is <code>Icon could not be found on the screen.</code>.</p>