Wavelet Based Normal and Abnormal Heart Sound Identification using Spectrogram Analysis

The present work proposes a computer-aided normal and abnormal heart sound identification based on Discrete Wavelet Transform (DWT), it being useful for tele-diagnosis of heart diseases. Due to the presence of Cumulative Frequency components in the spectrogram, DWT is applied on the spectro- gram up to n level to extract the features from the individual approximation components. One dimension- al feature vector is obtained by evaluating the Row Mean of the approximation components of these spec- trograms. For this present approach, the set of spectrograms has been considered as the database, rather than raw sound samples. Minimum Euclidean distance is computed between feature vector of the test sample and the feature vectors of the stored samples to identify the heart sound. By applying this algo- rithm, almost 82% of accuracy was achieved.