1. A method comprising: computing an overall image exposure score for an image; determining one or more face regions in the image; computing a face region exposure score for each face region; combining the overall image exposure score and each face region exposure score to generate an exposure quality score for the image; applying one or more of an overall exposure correction and an independent correction for each face region; and adjusting the exposure quality score according to a penalty value when a zone value for each color channel exceeds a predetermined threshold and adjusting each face region exposure score according to the penalty value when the zone value for each color channel exceeds the predetermined threshold, wherein computing the overall image exposure score comprises computing a clipped pixel score and a tonal distribution score based on a histogram of the image, and wherein computing the clipped pixel score comprises computing the clipped pixel score for each color channel of a plurality of color channels.