Developing operational performance metrics using image comparison metrics and the concept of degradation space

A technique for determining relative degradations from image metrics is pre sented along with a technique for predicting sensor performance from metric s. These techniques are illustrated with degradations of blur and noise in thermal imagery. These uses of metrics are depicted as mappings among a deg radation space, an image quality metric space, and an operational performan ce space. This technique has utility in sampled imagery applications where input and output image comparison is possible, e.g., validation of an infra red scene projector (IRSP), testing image compression algorithms, image sim ulation, etc. Such applications have a known input image and a degraded out put image. With the input image, one can characterize the output image in t erms of its degradations relative to the input. The concept of a degradatio n space leads to developing an Operational Performance Metric (OPM) in term s of more traditional Image Quality Metrics (IQMs). The technique is illust rated using empirical results for human observers performing recognition ta sks with thermal imagery in a degradation space of blur and noise. (C) 1999 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(99)01705-5 ].