Teager-Kaiser energy operator in Hilbert space for heart sound segmentation

摘要

In this paper an automatic heart sound segmentation scheme is proposed using Teager-Kaiser energy operator (TKEO) in Hilbert space. After pre-processing the heart sound signal, Hilbert envelope is computed and filtering is performed to obtain smooth envelope. TKEO is applied to this envelope signal to find more accurate boundaries of heart sounds. This energy operator depends only on first two time derivatives of the signal. It gives suitable boundaries for first and second heart sound separation. The heart sound boundaries for S1 and S2 are decided by markers derived from second derivative of Teager energy envelope. The heart sound signals are downloaded from the web site of the Department of Medicine, Washington University to evaluate the proposed algorithm. The segmented heart sound components along-with original recorded signals are heard by a number of signal processing experts. They found the performance of the proposed method satisfactory.