1. A method, comprising: receiving, by a processor, a plurality of images; determining, by the processor, an image similarity metric based on at least one pair of images of the plurality of images, wherein the similarity metric comprises determining an optical flow energy change difference measure (OFEDM) between optical flow fields comprising: calculating a first optical flow field between a current image and a previous frame and a second optical flow field between the previous image and a previous third image; comparing the first optical flow field to the second optical flow field by multiplying a scaled angle difference by a scaled magnitude difference for each pixel to arrive at a similarity scalar value for each pixel; and calculating a mean value of each of the similarity scalar values as the per pixel OFEDM; and detecting, by the processor, a shot change in the plurality of image upon the mean of the per pixel OFEDM exceeding a user-supplied threshold.