apd sapt 7 assig2

function filter_signal(input_file, output_file)

% Constants
F1 = 2000; % Frequency of the first component in Hz
F2 = 3200; % Frequency of the second component in Hz
Fs = 15000; % Sampling frequency in Hz

% Read the input audio file
[x, Fs_original] = audioread(input_file);

% Generate the input signal x(t)
t = 0:1/Fs:(length(x)-1)/Fs;
input_signal = cos(2*pi*F1*t) + cos(2*pi*F2*t);

% Plot the input signal in the time domain
figure;
subplot(3, 1, 1);
plot(t, input_signal);
xlabel('Time (s)');
ylabel('Amplitude');
title('Input Signal in Time Domain');

% Compute and plot the magnitude of the signal's frequency response
subplot(3, 1, 2);
f = linspace(0, Fs/2, length(input_signal)/2);
input_signal_fft = abs(fft(input_signal));
plot(f, input_signal_fft(1:length(f)));
xlabel('Frequency (Hz)');
ylabel('Magnitude');
title('Frequency Response of Input Signal');

% Design FIR filter to reject the first signal spectrum component
cut_off_freq = F1 / (Fs / 2);
filter_order = 50;
b = fir1(filter_order, cut_off_freq, 'high');

% Apply the FIR filter on the input signal
filtered_signal = filter(b, 1, input_signal);

% Plot the output signal in the time domain
subplot(3, 1, 3);
plot(t, filtered_signal);
xlabel('Time (s)');
ylabel('Amplitude');
title('Output Signal in Time Domain');

% Compute and plot the magnitude of the filtered signal's frequency response
figure;
filtered_signal_fft = abs(fft(filtered_signal));
plot(f, filtered_signal_fft(1:length(f)));
xlabel('Frequency (Hz)');
ylabel('Magnitude');
title('Frequency Response of Filtered Signal');

% Write the filtered signal to an output audio file
audiowrite(output_file, filtered_signal, Fs_original);

end