机构地区: 上海交通大学电子信息与电气工程学院图像通信与信息处理研究所
出 处: 《上海交通大学学报》 2003年第8期1312-1315,共4页
摘 要: 针对 MPEG- 2纯 I帧编码情况 ,在 MPEG- 2 TM5自适应量化控制算法的基础上 ,提出了一种基于平滑图像质量的高码率下自适应量化控制算法 .根据已编码帧的复杂度平滑分配各帧目标码字 ,利用非线性方法使宏块的量化因子变化平缓 ,以达到高码率下提高图像质量的目的 ,仿真结果表明 ,在相同码率下重建图像质量 (PSNR)优于 TM5算法 . By modifying TM5 quantization control algorithm, a novel quality smoothing adaptive quantization algorithm was proposed for only MPEG-2 intracoded picture. The proposed algorithm allocates target bits smoothly according to the coded pictures' complexity measure and makes the macroblock quantization factor smoothed by a nonlinear method. The coded pictures quality (PSNR), by the proposed algorithm, is better than the pictures quality coded by TM5 quantization control algorithm under the same bit-rate.