摘要
H.264是现在最新、最有前途的视频压缩标准。它的码率控制算法JVT-G012能获得良好的效果,但该算法在帧级码率控制上存在不足。在JVT-G012算法基础上,采取了一些帧级码率优化策略,用P帧亮度分量的平均绝对值差(MAD)比率来表示图像复杂度,同时根据编码图像复杂度和距离I帧的远近来合理有效的分配码率,增加了跳帧控制防止缓冲区发生上溢或者下溢,并且进行了场景切换检测。仿真采用Jm10.0,模拟了在恒定比特率(ConstantBitRate,CBR)条件下,对算法和JVT-G012算法产生的编码质量进行对比。仿真结果表明,与JVT-G012算法相比,算法能使码率控制算法具有更高的效率、更有效地提高编码图像质量。
H. 264 video coding standard becomes quite popular due to its high coding efficiency. But its Rate control algorithm such as JVT-G012 has limitation in the Frame -Layer rate control. To overcome this limitation ,this paper presents some improvement solutions based on the algorithm JVT-G012, such as introducing the ration of MAD to represent the complicity of the frame, optimizing the bit allocation algorithm in the frame layer based on its value of MAD ration and its distance to the I frame, adopting a method of frame skip to prevent the buffer overflow or under-flow. Simulations show that this scheme is more efficient and can provide images with higher quality compared to the rate control in JVT- G012.
出处
《计算机仿真》
CSCD
2008年第5期105-108,共4页
Computer Simulation
基金
国家“973”计划资助项目(2007CB307106)
