1. A method comprising: receiving, by a computing device, a first image and a second image; determining, by the computing device, whether a size of the first image is different from a size of the second image; if the size of the first image is different from the size of the second image: identifying, by the computing device, a best fit size, based on the size of the first image and the size of the second image; and resizing, by the computing device, at least one of the first image and the second image to the best fit size; generating, by the computing device, an image frame; for each pixel of the first image and each pixel of the second image in a corresponding location as the pixel of the first image: comparing, by the computing device, the pixel of the first image with the pixel of the second image to determine if the pixel of the first image is the same as the pixel of the second image; in a case that the pixel of the first image is the same as the pixel of the second image, drawing, by the computing device, a pixel in the corresponding location on the image frame with low intensity; and in a case that the pixel of the first image is not the same as the pixel of the second image, drawing, by the computing device, the pixel in the corresponding location on the image frame with high intensity.