A system and method for enhancing digital images is described. A digital image is transformed into a series of decomposed images in frequency bands, or different resolution grids. A decomposed image is noise suppressed and contrast enhanced. Representative value of signal at each pixel is computed based on contributions to signals from pixels in a neighborhood of the pixel. Lookup tables are applied to pixel values to selectively enhance signal in a predetermined range of signal strength. Another set of lookup tables are applied to pixel values to suppress noise components contained therein. Optionally, operations are applied to decomposed images to suppress quantum noise, enhance object edges or enhance global contrast, among others. These decomposed images, after signal enhancement and noise suppression, are then recombined to result in an enhanced image.