Quality estimators aspire to quantify the perceptual resemblance, but not the usefulness, of a distorted image when compared to a reference natural image. However, humans can successfully accomplish tasks (e.g., object identification) using visibly distorted images that are not necessarily of high quality. A suite of novel subjective experiments reveals that quality does not accurately predict utility (i.e., usefulness). Thus, even accurate quality estimators cannot accurately estimate utility. In the absence of utility estimators, leading quality estimators are assessed as both quality and utility estimators and dismantled to understand those image characteristics that distinguish utility from quality. A newly proposed utility estimator demonstrates that a measure of contour degradation is sufficient to accurately estimate utility and is argued to be compatible with shape-based theories of object perception.
© 2011 Optical Society of America
Original Manuscript: July 20, 2010
Revised Manuscript: November 5, 2010
Manuscript Accepted: November 8, 2010
Published: January 24, 2011
Vol. 6, Iss. 3 Virtual Journal for Biomedical Optics
David M. Rouse, Sheila S. Hemami, Romuald Pépion, and Patrick Le Callet, "Estimating the usefulness of distorted natural images using an image contour degradation measure," J. Opt. Soc. Am. A 28, 157-188 (2011)