(a) Original image
(b) JPEG-2000 compression DMOS = 17.7
(c) White noise DMOS = 23.5
Figure 15: When judging the quality of a distorted image containing near-threshold distortions, one tends to rely primarily on visual detection (often using point-by-point comparisons with the original image) in an attempt to locate any visible differences. (a) Closeup of original image bikes; (b) closeup of image bikes distorted via JPEG-2000 compression; (c) close-up of image bikes distorted by additive Gaussian white noise. DMOS values indicate differential mean opinion scores from the LIVE image database [124]. Figure from [139].