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This filter has been removed starting from Avisynth 2.53. Use Tweak and Levels, as appropriate.
HSIAdjust(clip clip, float h, float s, int min, float gamma, int max):
Adjusts colors in HSI space. Tweak works better except it doesn't have gamma. Since Tweak is technologically leaps and bounds ahead of HSI, they should be merged (just add gamma to tweak) or HSI should simply be dropped before someone gets dependant on it. HSI behavior is unpredictable at anything more than very minor corrections.
h (-180.0 - 80.0) is used to adjust the color hue of the image. Positive values shift the image towards red. Negative values shift it towards green.
s (0.0 - 10.0) is used to adjust the color saturation of the image. Values above 1.0 increase the saturation. Values below 1.0 reduce the saturation. Use s=0 to convert to Greyscale.
Min (0-255) and Max (0-255) have the effect of clipping values below or above those luminance values specified from the input and stretching the rest into the range 8-240.
gamma (>0) specifies the gamma channel. If the overall gamma of an imaging system is 1.0, its output is linearly proportional to its input. This means that the ratio between the intensities of any two areas in the reproduced image will be the same as it was in the original scene. If the gamma is larger than one it means that intensities of any two areas in the reproduced image will be larger as it was in the original scene.
