Wavelet Based ECG signal Compression using Run Length Encoding

Wavelet is a powerful tool for signal coding especially bio-signal processing. Wavelet transform is used to represent the signal in time–frequency representation which is better suited for detecting and removing redundancies. A algorithm for wavelet based ECG signal compression is presented in this paper. Discrete Wavelet Transform (DWT) where db7 is selected as the mother wavelet for analysis as it is found to be most similar to the morphology of QRS complexes. Thresholded wavelet coefficients are coded with RLC. In here, we use RLC algorithm, because of it's good performance on compression. One of the main advantages of this method is lower calculation complexity in comparison with other methods. This algorithm is tested for different records from MIT–BIH arrhythmia database. A compression ratio of 74.77% is achieved for MIT–BIH arrhythmia database record 117 with a percent mean square difference as 0.27%. KeywordsCompression, Discrete Wavelet Transform, ECG, MIT-BIH, RLC