1. A method of processing a digital, input image, comprising: providing said digital input image, I, in physical memory, said input image having color information in a native color space for each image pixel; providing a processing device coupled to said physical memory to access said input image I and create an output image, h, by implementing the following steps: (a) applying the following sequence to said input image I, h σ , ɛ ( x ) = ∑ y ∈ Ω x ( f s σ ( x , y ) L xy ɛ I ( y ) ) ∑ y ∈ Ω x ( f s σ ( x , y ) L xy ɛ ) where x and y are pixel locations over an image grid, and Ω x is the neighborhood induced around the central pixel x; f s (x,y) measures the spatial affinity between pixels at x and y; parameter σ controls an amount of spatial blurring; L xy ε is a laplacian matrix that provides positive color affinity value for two examined pixels, x and y, that have the same color and provides a zero color affinity value for pixels with different color; parameter ε is a regularization term whose relative weight determines the smoothness of output image h.