1. An image processing method to emulate image content as it will appear when viewed on a target display, the method comprising: receiving an input image prepared on a source display, wherein the source display has different display characteristics than the display characteristics of the target display; obtaining one or more image statistics data of the input image; accessing a display function that characterizes how the behavior of the target display changes in response to characteristics of an image being viewed on the target display; computing based on the obtained image statistics data of the input image one or more parameters of the display function; obtaining one or more color image statistics relating to relative proportions of primary colors in the input image by processing the input image; accessing a second display function that characterizes how the behavior of the target display changes in response to characteristics of an image being viewed on the target display; computing based on the obtained color image statistics data of the input image one or more parameters of the second display function; and generating an output image based at least on the input image, the display function, the computed parameters of the display function, the second display function, and the computed parameters of the second display function, wherein the input image comprises pixel values corresponding to each of red, green and blue primary colors, wherein computing the color image statistics comprise computing: R R + G + B and G R + G + B and B R + G + B where R, G and B are respectively sums of the pixel values corresponding to each of red, green and blue primary colors for the whole input image or a local area within the input image.