Wavelet based 2-D ECG compression by implementing of SPIHT algorithm and RL coding

A two dimensional (2-D) wavelet based electrocardiogram (ECG) data compression method is presented which employs a set partitioning in hierarchical trees (SPIHT) and run length (RL) coding. The proposed 2-D approach utilizes the fact that ECG signal generally show redundancy between adjacent beats and between adjacent samples. Meanwhile a set of wavelet functions for implementation in 2-D ECG array was examined. Eight different wavelets are evaluated for their ability to compress ECG. Results show that RL coding increases the compression ratio in the same error. Moreover biorthogonal-6.8 is clearly the best performer in the statistical measure among the eight different evaluated wavelets.