Adding rate control to JPEG-LS

Abstract

In this paper, we present a low cost approach to design rate control algorithm for JPEG-LS, the latest JPEG lossless/near lossless image compression standard, to achieve an information loss adaptive and rate-controlled near lossless image compression. The design incorporates the major features of data compression in JPEG-LS and seamlessly adds an information loss distribution scheme into the standard to adjust the compression ratio in accordance with the variance of image content and lock the final compression ratio at a desired target specified by users. The algorithm proposed also satisfies the general requirement for industrial standards as such that: (i) the complexity of JPEG-LS is maintained at a similar level without any significant increase; (ii) the compression ratio at its near lossless compression mode is controlled at a target bit rate within the range of near lossless compression; (iii) the visual perception quality is even better than the original JPEG-LS in smooth areas; (iv) the image qua lity in terms of PSNR is maintained competitive to the original JPEG-LS. Extensive experiments confirm the above statements when the original JPEG-LS is used as our benchmark, which is not rate controlled.