基于率失真优化和PSB系数位移的ROI编码新方法

Novel ROI coding method based on rate-distortion optimization and PSB coefficients shift

小波系数移位和率失真优化的比率控制是实现ROI编码常用的两种策略。小波系数移位的方法能准确的恢复选择的ROI区域,但会影响编码的效率。而率失真优化的方法有好的编码效率但ROI区域重建精度受到影响。将两种机制结合,本文提出了一种率失真斜率提升和PSB系数移位相结合的ROI编码新方法。实验结果表明,新算法在同等编码效率及计算复杂度下,获得了良好的ROI重建精度。

It provides ROI coding through two mechanisms： either modifying wavelet coefficients or using rate-distortion optimization techniques. Although ROI coding methods based on the modification of wavelet coefficients provide an excellent accuracy to delimit the ROI area, they significantly penalize the coding efficiency. On the other hand, methods based on rate-distortion optimization improve the coding efficiency but, so far, have not been able to achieve the intended fine-grain accuracy. Combining above two ROI coding methods, this paper presents a new ROI coding method using rate-distortion slope advance integrated with Partial Significant Bitplanes Shift （PSBShift）. The experimental results show that the novel algorithm achieves a fine-grain accuracy, while preserves its coding efficiency and computation complexity.