使用新的码字分割方法的快速LBG算法

Fast LBG algorithm using new codeword splitting method

针对LBG算法中初始码书生成存在盲目性的问题,提出了一种基于训练向量集合分量之间的相关性进行码向量分割的方法。在迭代过程,记录每一个码向量所映射的训练向量子集;生成新的初始码书时,首先计算被分割码向量所映射的训练子集的第一个分量与其他各分量之间的协方差;根据协方差来分割相应的码向量。实验表明,应用新的码向量分割机制后,LBG算法中的迭代次数和运行时间减少了约10%左右。

To alleviate the blindness of Linde-Buzo-Gray algorithm （LBG algorithm） while generating initial codebook,a new codeword splitting method based on covariance of training vector is proposed.Subset of training vector mapped to each codeword is recorded in the iteration step.In the codeword splitting step,covariance between column one and other columns of each subset is calculated and the corresponding codeword is split into twos according to the covariance.Experiment results show that the number of iteration and runtime of LBG algorithm are reduced about 10% by applying the new codeword splitting mechanism.