Giavapps CC extension for GameMaker: Studio (developed and produced by Luigi Piscopo) is going to bring you a cool set of features for improving your game graphics with Color Correction Shaders.
This Extension includes an emulation of the Levels feature which you can find in Adobe Photoshop.
Giavapps CC Shaders have been optimized for working on mobile devices and older hardware with GLSL instruction limits.
With Giavapps CC Demo you can easily test these Shaders with your own images (.png, .jpg or .jpeg) and then export Shader Uniforms in no time.
Besides, Giavapps CC is inexpensive, well documented, light and very easy to use.
This Extension has been tested on the following target platforms:
You can find the full documentation with code examples at the following link:
Contrast Saturation Brightness
Hue Saturation Value