1. A method for estimating the image capture date of a photo, comprising: identifying, by a processor, image characteristics of an undated photo; comparing, by the processor, the image characteristics of the undated photo to image characteristics relating to a plurality of reference photos, each of the plurality of reference photos having an established date, wherein the compared image characteristics comprise graininess and wherein graininess is represented by frequency domain data; and estimating, by the processor, the date of the undated photo based on the similarity of the image characteristics of the undated photo to one or more of the image characteristics of the reference photos.