基于无线传感网络的DVC码率估计算法

Rate Estimation Algorithm for Distributed Video Coding Based on Wireless Sensor Network

面向战场环境侦察,研究应用于无线传感器网络的分布式视频编码系统,提出了一种分布式视频编码系统的码率估计算法。该算法首先通过对相邻关键帧取均值生成参考帧,由参考帧估计编码图像各区域的运动强度,并将编码图像分为低运动区域和高运动区域。对于低运动区域,由参考帧代替边信息来计算边信息与编码数据之间的交叉概率,而其他区域由编码信息和差值分布的概率模型估计交叉概率,然后由交叉概率计算编码比特平面的码率。实验结果表明,文中算法的码率估计值与已有算法相比更为准确。

In this paper,a distributed video coding system and the relevant rate estimation algo rithm in the wireless sensor network is developed for battlefield reconnaissance. With this algorithm, a reference frame is firstly generated by a simplified interpolation processing with two adjacent key frames and the encoding frame is divided into two parts with different motion intensity. For the blocks with low motion,the cross ratio of each bitplane is estimated with the encoding data and the reference frame instead of the side information. As for the blocks with high motion ,the proposed method estimates the cross ratio of each bitplane with the side information and the Laplacian distribution of difference. Then the rate of encoding bitplane lossless decoded in the decoder is derived from the cross ratio. The simulation result indicates that the rate estimation achieved by the proposed algorithm is more precise than other algorithms currently used.