Adding rate control to JPEG-LS

In this paper, we present a low cost approach to design rate control algori thm for JPEG-LS, the latest JPEG lossless/near lossless image compression s tandard, to achieve an information loss adaptive and rate-controlled near l ossless image compression. The design incorporates the major features of da ta compression in JPEG-LS and seamlessly adds an information loss distribut ion 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 com plexity of JPEG-LS is maintained at a similar level without any significant increase; (fi) the compression ratio at its near lossless compression mode is controlled at a target bit rate within the range of near lossless compr ession; (iii) the visual perception quality is even better than the origina l JPEG-LS in smooth areas; (iv) the image quality in terms of PSNR is maint ained competitive to the original JPEG-LS. Extensive experiments confirm th e above statements when the original JPEG-LS is used as our benchmark, whic h is not rate controlled. (C) 2001 SPIE and IS&T.