Determination of features for heart sounds by using wavelet transforms

A method is presented to determine features of heart sounds. A wavelet transform is applied to a window of two periods of heart sounds. Two analyses are realized for the signals in the window: segmentation of the first and second heart sounds, and extraction of the features. After the segmentation, feature vectors are formed by using the wavelet detail coefficients at the sixth decomposition level. The best feature elements are analyzed by using dynamic programming.