A computer program product includes instructions for a processor to perform a method of improving image structure and coherence, and/or for simplification/stylization. The method includes inputting the image, by: scanning the image; image capture using a camera; and/or image creation using a computer. Multi-channel images are converted into a single-channel image, which is separated into a first image component—the high spatial frequencies, and a second component image—the low spatial frequencies. The first and second component images are each formed by filtering to remove frequencies outside of respective upper and lower threshold frequencies. A gain multiplier is applied to the filtered first and second component images to control detail amplification. The first and second component images are each blurred at the respective upper and lower threshold frequencies. An improved stylized composite image results by subtracting the gain multiplied first component image from the gain multiplied second component image.