ImageAdjust — adjust levels, brightness, contrast, gamma, etc.
ImageHistogram — histogram of levels by channel
ImageLevels — tally of levels in each channel
ColorConvert — convert between color spaces
ColorSeparate,
ColorCombine — separate, combine color channels
Binarize — reduce any image to black and white
ColorQuantize — reduce the color palette of an image
ImageApply — apply an arbitrary function to each pixel value
ColorData — data on a large number of useful color schemes
