Comparison of JPEG 2000 and other lossless compression schemes for digital mammograms

In this study, we propose JPEG 2000 as an algorithm for the compression of digital mammograms and the proposed work is the first real-time implementation of JPEG 2000 on a mammogram image database. Only the lossless compression mode of JPEG 2000 was examined to ensure that the mammogram is delivered without distortion. The performance of JPEG 2000 was compared against several other lossless coders: JPEG-LS, lossless-JPEG, adaptive Huffman, arithmetic with a zero order and a first order probability model and Lempel-Ziv Welch (LZW) with 12 and 15 bit dictionaries. Each compressor was supplied the identical set of 50 mammograms, each having a resolution of 8bits/pixel and dimensions of 1024 x 1024. Experimental results indicate JPEG 2000 and JPEG-LS provide comparable compression performance since their compression ratios differed by 0.72% and both compressors also superseded the results of the other coders. Although JPEG 2000 suffered from a slightly long L-er encoding and decoding delay than JPEG-LS (0.8s on average), it is still preferred for mammogram images due to the wide variety of features that aid in reliable image transmission, provide an efficient mechanism for remote access to digital libraries and contribute to fast database access.