Wavelet-Threshold based ECG Compression with Smooth Retrieved Quality for Telecardiology

A new novel wavelet-threshold based ECG signal compression method is proposed using linear phase biorthogonal 9/7 discrete wavelet transform, uniform scalar zero zone quantizer (USZZQ) and Huffman coding of the difference between two consecutive index of the significant coefficients. The compression performance of the proposed method is better compared to EZW, SPIHT, ASEC and other wavelet-threshold based coders. The proposed method is tested for the MIT-BIH arrhythmia record 119 and a compression ratio of 21.8:1 is achieved with PRD value of 3.7166% which is much lower as compared to the reported PRD value of 5.0% and 5.5% of SPIHT and ASEC, respectively. The proposed method requires less computation time since it does not need QRS detection, period normalization, amplitude normalization and mean removal. Hence, the proposed method can be used for the transmission of ECG signal over the band limited telephone networks.