A low-cost content-adaptive and rate-controllable near-lossless image codec in DPCM domain

It remains an important issue for any image codec to optimize the balance between the reconstructed image quality and the rate-controllable compression ratio. A content adaptive information loss distribution scheme is proposed to design a low-cost and rate-controllable image codec. This design exploits the principle that any extra information loss required by the rate-control should be introduced only to those areas where the local texture analysis reveals that human visual perception is less sensitive to the incurred distortion. Therefore, while rate-distortion theory may enable us to optimize PSNR measurement of quality in rate control design, the proposed technique is able to optimize the perceptual quality of the reconstructed images. Experimental results are reported to support this statement for the performance of the proposed algorithm, benchmarked by the nonrate-controlled JPEG-LS.