title: Change contrast, brightness, saturation, or color of UIImage
body: <p>I'm looking for a good way to modify some elements of <code>UIImage</code> like brightness, contrast, saturation (for colored images), and colors (colorize).</p>
  
  <p>For now I use per pixel operations but it's not very fast.
  For each pixel in the image, I modify the color data for contrast, brightness etc. I use some sources from <a href="https://github.com/coryleach/UIImageAdjust" rel="noreferrer">UIImageAdjust</a> for brightness and contrast.</p>
  
  <p>I'm looking for a more effective way to like blending the images with color (a faster way, but i can get what i want with CGBlendMode).</p>
  
  <p>Any ideas ?</p>