基于嵌入式零树小波的心电信号压缩算法及实现

摘要

According to the limitations of data storage and transmission in portable wireless electrocardiogram (ECG) monitoring device and the particularity of ECG,an embedded zero-tree wavelet(EZW)based compression algorithm is proposed in this paper. The algorithm modifies the basic EZW coding algorithm to improve the compression rate and speed of compression,by merging the first and second iteration,and prejudging whether the zero-tree appeared in the first iteration is always a zero-tree. Simulation and practical running were carried out to test the improved algorithm by using the MIT-BIH arrhythmia database,and on MICAZ nodes separately. Experiments show that the algorithm has higher compression ratio than EZW,and is more suitable for ECG signal compression on wireless device.%针对便携式无线心电监护设备在数据存储及传输上的局限性,结合心电信号的特点,提出了一种基于嵌入式零树小波(Embedded Zero-tree Wavelet,EZW)算法的压缩算法.通过对EZW算法第一、二次迭代加以合并,并预先判断和标记第一次迭代出现的零树是否在整个编码过程中始终是零树,以提高算法的压缩率和运算效率.以MIT-BIH心律不齐数据库为样本数据集进行仿真,同时在MICAZ节点上作实际运行测试.实验证明,该算法相比于EZW算法压缩率更高,能更好地应用于无线设备上的心电信号压缩.