一种分层次B帧双向预测直接模式

Hierarchical B picture bi-prediction direct mode

分层次B帧是一种基于闭环运动补偿的时域可伸缩性视频编码,其特点是解码重构后的B帧可作为参考帧。针对分层次B帧的特点,提出一种新的B帧双向预测直接模式。通过挖掘相邻帧间的时域相关性,利用B帧作为参考帧时的前后向运动矢量进行时域缩放,精细当前块在直接模式下的运动矢量精度。仿真实验证明,该方法相对于传统的编码方式,编码性能增益平均提高0.46 d B。

Hierarchical B picture is a temporal scalability video coding scheme which is based on close loop motion compensation temporal filter. It employs the reconstruetured B picture as referenced picture. In the light of characteristics of hierarchical B picture, this paper proposed a new B picture bi-prediction direct mode. By mining the temporal relationship among the adjacent pictures and scaling the forward or backward motion vector of the B referenced picture, the accuracy of the obtained motion vectors in current block could be refined. The simulated results show that the coding performance of the proposed method gains an average of 0.46 dB compared with traditional method.