一种改进的基于离散余弦变换的声音压缩算法

摘要：声音压缩传输是异常声音检测系统中的重要模块。针对现有算法不能满足系统实时性要求的缺陷，提出一种采用角度误差限定分段拟合和离散余弦变换(DCT)的声音压缩算法。该算法先设置合理的角度误差，从时域波形的第一个采样点开始按照几何夹角和限定的角度误差逐点判断是否可以压缩，分段模拟信号波形，然后采用传统的基于离散余弦变换算法，选取合适的阈值再次进行压缩。实验结果表明，与传统的声音压缩算法相比，提出的算法在压缩效果上有较明显的改善。

An Improved Sound Signal Compression Algorithm Based on Discrete Cosine Transform

Sound compression and transmission is very important part in abnormal sound detection system. However, the existing sound signal compression methods cannot meet the real time requirements of the system. For this situation, the paper proposed a sound signal compression algorithm adopted piecewise fitting of limited angle error and discrete cosine transform. The algorithm first set a reasonable angle error, according to waveform characteristics, from the first sampling point by point to determine whether it can be compressed according to the geometric angle, then piecewise analog sound signal waveform, after that using the traditional algorithm based on discrete cosine transform, select the appropriate threshold to compress again. Simulation results show that, the proposed algorithm has better performance compared with the traditional compression algorithm.