Equalizer

This plugin offers three methods of equalization, with several options to make this process as much as possible exploitable. In FACT, what is equalization? Roughly speaking, equalization is a process that generate for each image the "optimal" curve which once applied to that image would improve contrast, in a relevant way. To reach that result, the process exploits intensively the histogram of frequencies. *Here`s a Brief description of the three methods:*Levels: Equalize the three channels R,G,B in an independent way. Can improve dramatically contrast. However this method often introduces important distortions of tints. Reserve it for particular cases.*Contrast: Apply the same curve to the three channels. Frequencies of the three channels are totalized here to generate the curve. This method is GeneRally the most satisfying.*Luminosity: Preserve hue and saturation. Luminosity is modified, or directly by equalizing this one (option: perceptual), or indirectly by equalizing one of the three channels.*Without adjustments, equalization gives barely interseting results. That`s why three parameters were introduced:* Highlights/Shadows: Specify the percentage of lightest and darkest pixel you wish to ignore.*Amount: parameter "amount" allows to moderate the extreme character of equalization. When this parameter is null, the plugin proceeds to a simple linear adjustment by exploiting highlights and shadows settings.