Separate and plot individual filter responses

I am trying to create a plot similar to the attached image! I want to see the individual response each filter gives while displaying the center frequency of that filter on the y, adding together all of the responses at the top. I want to do this to display how much each filter is contributing and where it is most active. I was trying to use plot with CenterFreqs as my y but keep getting errors. This is what I have:

% Parameters

fs = 16e3;

t = 0:(1/fs):0.03;

t = t(:); % ensure column vector

numFilts = 32;

signal_freq = 100; % frequency of input signal

range = [50 8000];

gammaFiltBank = gammatoneFilterBank(range, numFilts, fs); % set fs explicitly

% Generate input signal

A=1;

input_signal = A*sin(2*pi*signal_freq*t);

% Get the center frequencies of the filters

CenterFreqs = getCenterFrequencies(gammaFiltBank);

% Process the input signal through the selected filters

output_signal = gammaFiltBank(input_signal);

Thank you for your time!

[Umar]

Hi @S,

Please see updated code snippet below, please customize your modified code plots based on your preferences. Please see brief summary of code snippet below along with your modified code snippet.

% Parameters

fs = 16e3;

t = 0:(1/fs):0.03;

t = t(:); % ensure column vector

numFilts = 32;

signal_freq = 100; % frequency of input signal

range = [50 8000];

gammaFiltBank = gammatoneFilterBank(range, numFilts, fs); % set fs explicitly

% Generate input signal

A = 1;

input_signal = A * sin(2 * pi * signal_freq * t);

% Get the center frequencies of the filters

CenterFreqs = getCenterFrequencies(gammaFiltBank);

% Process the input signal through the selected filters

output_signal = gammaFiltBank(input_signal);

% Plot individual filter responses with center frequencies on the y-axis

figure;

for i = 1:numFilts

    subplot(numFilts, 1, i);

    plot(t, output_signal(:, i));

    title(['Filter Response - Center Freq: ', num2str(CenterFreqs(i)), ' Hz']);

    if i == numFilts

        xlabel('Time (s)');

    end

    ylabel('Amplitude');

    grid on;

end

% Sum up the responses of all filters

combined_response = sum(output_signal, 2);

% Plot the combined response along with individual filter responses

figure;

for i = 1:numFilts

    subplot(numFilts+1, 1, i);

    plot(t, output_signal(:, i), 'Color', [0.8 0.8 0.8]); % Individual filter responses

    ylabel(['Amplitude - Filter ', num2str(i)]);

end

subplot(numFilts+1, 1, numFilts+1);

plot(t, combined_response, 'k', 'LineWidth', 2); % Combined response

xlabel('Time (s)');

ylabel('Amplitude - Combined');

title('Combined Response and Individual Filter Responses');

% Display contribution of each filter to the combined response

figure;

bar(CenterFreqs, sum(output_signal, 1), 'b');

xlabel('Center Frequency (Hz)');

ylabel('Contribution to Combined Response');

title('Filter Contribution to Combined Response');

Please see attached.

Brief summary of code snippet

*The initial section of the code sets up parameters such as the sampling frequency fs, time vector t, number of filters numFilts, signal frequency signal_freq, frequency range range, and initializes the gammatone filter bank gammaFiltBank.

*An input sinusoidal signal is generated with a specific amplitude A and frequency signal_freq over the time vector t.

*The function getCenterFrequencies is used to extract the center frequencies of the gammatone filters in the bank.

*The input signal is processed through the gammatone filter bank using the gammaFiltBank function, resulting in output_signal, which contains the responses of each filter.

*A figure is created to display the responses of each filter individually over time. Each subplot represents a filter response with its corresponding center frequency.

*The responses of all filters are summed up to create a combined_response that represents the combined output of the filter bank.

*Another figure is generated to show the combined response along with the individual filter responses. The combined response is plotted in a separate subplot with a thicker line for clarity.

*A bar graph is plotted to illustrate the contribution of each filter to the combined response. The x-axis represents the center frequencies of the filters, and the y-axis shows the contribution values.