In this paper, we propose a mathematically defined universal
image quality index. By “universal,” we mean that the quality
measurement approach does not depend on the images being
tested, the viewing conditions or the individual observers.
More importantly, it must be applicable to various image
processing applications and provide meaningful comparison
across different types of image distortions. Currently, the PSNR
and MSE are still employed “universally,” regardless of their
questionable performance. This work attempts to develop a
new index to replace their roles.