clear all;
close all;
%% Read a .wav file
filename='D:\Data\subject_32.wav'; %% Specify filename to read
[y,fs]=audioread(filename);
% This inbuilt MATLAB function reads the audio file from the specified address.
% The sampling frequency(fs) is read from the audio file directly.
% For our dataset,sampling frequency is 2000 Hz.
% y - stores the fPCG raw data.
%% Plotting the Data
t=(1:length(y))/fs; %% Time of the signal in seconds
plot(t,y); %% this function plots the time vs signal.
%% Comb filter
fo=50; %% Cut-off frequency for comb filter
q=35; %% Quality factor
bw = (fo/(fs/2))/q; %% Bandwidth of the filter
[b,a] = iircomb(fs/fo,bw,'notch'); %% and b are the filter coefficients