how can obtain the period information from wave format heart sound file for calculating BPM?

I need to calculate period information from wave format sound by MATLAB code. I need it for calculating heart rate in BPM (Beat Per minute).

Answer 1

[Wayne King]

You can use spectral analysis and/or look at the autocorrelation.

Read the data into MATLAB using audioread() or wavread()

Answer 2

[Saifuddin Chowdhury]

I can read wave format file. But i don't know autocorrelation code to obtain period information.

[Wayne King]

do you have the signal processing toolbox? If so, see xcorr() Is this a speech sample?

[Saifuddin Chowdhury]

This is heart sound sample.

[Wayne King]

Sorry, you said that earlier, my mistake. How big is the file? Can you simply attach it, or read it in MATLAB first and save the data as .mat file and attach that. Also, we need to know the sampling frequency.

Answer 3

[Wayne King]

Based on your data and the sampling rate

The main oscillation in this data is around 90 Hz.

 [Pxx,F] = periodogram(y,[],length(y),fs);
 plot(F,Pxx)
 set(gca,'xlim',[0 200])
 [~,idx] = max(Pxx);
 F(idx)

You can confirm by using the autocorrelation:

[c,lags] = xcorr(y,y,480,'coeff');
stem(lags(481:end),c(481:end));
[Pxx,F] = periodogram(c,[],length(c),fs);
[~,idx] = max(Pxx);
F(idx)