1. A method for editing a multi-channel image comprising a plurality of pixels, the method comprising: inputting one or more multi-channel images into a computer programmed to execute the steps of: applying a transformation or filter to the one or more multi-channel images to separate at least a portion of the one or more multi-channel images into a specular component and a diffuse component; changing one or more of the separated components; and combining the one or more changed separated components with the other separated components to produce an output comprising an edited image.