Visual comparison of JPEG 2000 versus conventional JPEG

One difficulty in image compression research is designing meaningful performance metrics. Purely numerical measures such as PSNR are unsatisfactory because they do not correlate well with human assessment. We introduce a method of subjective image evaluation for image compression called calibrated rank ordering (CRO). CRO is attractive because it produces substantial numerical results without excessive burden on the observers. Using CRO we compare traditional JPEG with JPEG 2000 in a variety of modes. We also consider the effect of differing images sources, i.e., digital still camera vs. film scan. Finally, we compare and contrast the artifacts of both JPEG and JPEG 2000.