1. A method comprising: examining a received image and detecting a subject depicted in a subject portion of the received image; determining a likelihood that the subject portion will be used as a replacement to be inserted in place of one or more corresponding subject portions in future images examined at a later time; and storing the subject portion, or a reference thereto, in an image cache in response to the determined likelihood being greater than a predetermined threshold, wherein the image cache is available to be searched for the subject portion and other portions of images to replace corresponding portions of future images.