PERFORMANCE ANALYSIS OF VISUALLY LOSSLESS IMAGE COMPRESSION

In many applications, it is desirable to provide visually lossless (but, in fact, lossy) compression of still images. This can be done using modern visual quality metrics and iterative image compression/decompression procedure for setting a proper parameter of a coder for a given image. Performance of such a procedure is analyzed for a wide set of grayscale images and components of color images for several lossy compression techniques, both standard and advanced ones. Results are obtained for two human vision system (HVS) metrics, PSNR-HVS-M and MSSIM and they are in good agreement between each other. It is shown that a provided compression ratio (CR) considerably depends upon complexity of an image subject to lossy compression. The provided CR varies in very wide limits (from 3 to 30 for the used values of the metrics). It is also demonstrated that modern advanced HVS-adapted coders are able to produce by 1.2...1.6 larger CR than standards JPEG and JPEG2000 for the same visual quality.