Change contrast, brightness, saturation, or color of UIImage

I'm looking for a good way to modify some elements of UIImage like brightness, contrast, saturation (for colored images), and colors (colorize).

For now I use per pixel operations but it's not very fast. Fo开发者_如何学运维r each pixel in the image, I modify the color data for contrast, brightness etc. I use some sources from UIImageAdjust for brightness and contrast.

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).

Any ideas ?

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Have a look at Apple's demo app GLImageProcessing, it's really fast: