A Phase Based Image Comparison Technique
G.P. Lorenzetto, Peter D. Kovesi · UWA Profiles and Research Repository (UWA) · 1999
Two of the most popular image quality measures are the root mean square and signal-to-noise ratio. Unfortunately these measures are simple tallies of pixel difference and provide no information about the type of degradation present. Although simple, and consequently provide computational benefits, the RMS and SNR measures cannot meaningfully be applied to images containing text or binary images. Pixel tally measures are also unable to measure perceptual distortion. Take the case of two identical images, one translated one place to the right. These images still appear similar, but an RMS type error will return a large difference.