Table 3 Time-frequency domain
From: Localization and classification of heart beats in phonocardiography signals —a comprehensive review
Study | Year | Pre-processing techniques | Localization techniques | Classification techniques | Beat types | Data set | Signals statistics | Evaluation metrics | Results |
|---|---|---|---|---|---|---|---|---|---|
Zhang et al. [52] | 2017 | Resampling, filtering, and normalization | Time, spectrogram, and regression | SVM | Normal and abnormal heart sounds | PASCAL CHSC 2011 | 176 dataset A and 507 dataset B samples | Precision, sensitivity, and specificity | 60–76%, 89–100%, and 39–90% |
Zhang et al. [53] | 2017 | Resampling, filtering, and normalization | Time, tensor representation and, feature extraction | SVM | Normal and abnormal heart sounds | PASCAL CHSC 2011 and 2016 PhysioNet challenge | 176 dataset A and 507 dataset B samples | Precision, sensitivity, and specificity | 25–67%, 44–100%, and 39–64% |
Singh et al. [50] | 2017 | – | Time, probability, and spectrogram- based processing | Time, probability, and spectrogram-based processing | Normal and abnormal heart sounds | National Institute of Health, India | Signal recoding from 45 healthy and 45 patients | – | – |
Barma et al. [51] | 2016 | S3 separation and decomposition by HVD | TFR by SPWVD | Time duration-based classification | 82 cycles | Data collected from Texas Heart Institute and Michigan Heart Sound and Murmur Library dataset | – | Efficiency | 93.9% |
Gavrovska et al. [48] | 2014 | Signal decimation | Pseudo-affine Wigner-Ville distribution and Haar wavelet lifting, autocorrelation, and Shannon envelogram | Pseudo-affine Wigner-Ville distribution and Haar wavelet lifting, autocorrelation, and Shannon envelogram | Normal heart sounds | Data acquisition at University Children Hospital in Belgrade, Serbia | Signal recoding from 35 healthy and 55 patients | Recall and precision | 90.41 and 96.39% |
Boutana et al. [46] | 2011 | – | Spectrogram with Reyni marginal entropy | Spectrogram with Reyni marginal entropy | Normal heart sounds, early aortic stenosis, late aortic stenosis, pulmonary stenosis, and mitral regurgitation | E-General Medical | 6 signals | – | – |
Debbal et al. [47] | 2005 | – | STFT, CWT, and WD | STFT, CWT, and WD | Normal hear t sounds, mitral stenosis, split S2, aortic insufficiency, and stenosis | - | - | - | - |
Zhang et al. [45] | 1998 | – | MP-based Wigner distribution | MP-based Wigner distribution | Normal heart sounds and murmurs | Private dataset | 11 signals | Error reduction | – |