NIIRS and objective image quality measures

Abstract

The introduction of image distortion during compression is of widespread concern, to the extent that the nature and size of the distortion may influence the choice of codec. The ability to quantify the distortion for particular applications is therefore highly desirable, particularly when options for new compression standards (such as JPEG 2000) are being considered. We report on the performance of several degradation measures that have been evaluated on optical imagery having previously undergone compression by the JPEG, wavelet and VQ codecs. The results show the relationship between the subjective National Imagery Interpretability Rating Scale (NIIRS) and several numerical image quality measures. An insight is provided into factors influencing NIIRS evaluation.