Electrocardiogram data compression algorithm based on the linear prediction of the wavelet coefficients

This paper describes a new algorithm, based on the compression of the linearly predicted residuals of the wavelet coefficients, for electrocardiogram (EGG) compression. The main goal of the algorithm is to reduce the bit rate while keeping the reconstructed signal distortion at a clinically acceptable level. The input signal is divided into blocks and each block goes through a discrete wavelet transform; then the resulting wavelet coefficients are linearly predicted. In this way, a set of uncorrelated transform domain signals is obtained. These signals are compressed using modified run-length and Huffman coding techniques. The error corresponding to the difference between the wavelet coefficients and the predicted coefficients is minimized in order to get the best predictor. The method is assessed through the use of percent residual difference (PRD) and visual inspection measures. By this compression method small PRD with high compression ratio and low implementation complexity are achieved