Near-Optimal Low-Cost Distortion Estimation Technique for JPEG2000 Encoder

Optimal rate-control is a very important feature of JPEG2000 which allows simple truncation of compressed bit-stream to achieve best image quality at a given target bit-rate. Accurate distortion estimation with respect to allowed bit-stream truncation points, is essential for rate-control performance. In this paper, we address the issues involved in accurate distortion estimation for hardware oriented implementation of JPEG2000 encoding systems with generic block coding capabilities. We propose a novel hardware friendly distortion estimation technique. Rate control based on the proposed technique results in only an average 0.02 dB PSNR degradation with respect to the optimal distortion estimation approach used in the software implementations of JPEG2000. This is the best performance reported in comparison to existing techniques. The proposed technique requires only an additional 4096 bits per block coder which is 80% less than the memory requirements of optimal approach