flanger with feedback

inputFilePath = 'input.wav';
outputFilePath = 'output_flanger.wav';
maxBufferSize = 1000;
minBufferSize = 200;
modulationDepth = 0.5;

flanger(inputFilePath, outputFilePath, maxBufferSize, minBufferSize, modulationDepth, 0.5);
function flanger(inputWavefile, outputWavefile, maxBufferSize, minBufferSize, modDepth, feedback)
    % Read the input wavefile
    [inputSignal, Fs] = audioread(inputWavefile);

    % Initialize circular buffer and other parameters
    circularBuffer = zeros(maxBufferSize, 2);
    bufferIndex = uint32(1);
    modFrequency = 0.25; % You can adjust this value

    % Prepare the output signal
    outputSignal = zeros(size(inputSignal));

    % Create time vector for plotting
    t = (0:length(inputSignal) - 1) / Fs;

    % Initialize plots
    figure;

    % Plot the input wave
    subplot(2, 1, 1);
    plot(t, inputSignal);
    title('Input Wave');
    xlabel('Time (s)');
    ylabel('Amplitude');

    % Apply flanger effect with feedback
    for n = 1:length(inputSignal)
        % Calculate delay time using modulation
        delayTime = minBufferSize + modDepth * sin(2 * pi * modFrequency * n / Fs);
        delaySamples = round(delayTime * Fs);

        % Circular buffer read
        readIndex = mod(bufferIndex - delaySamples - 1, maxBufferSize) + 1;
        delayedSample = mean(circularBuffer(readIndex, :));

        % Apply the flanger effect to the input sample with feedback
        outputSignal(n) = inputSignal(n) + delayedSample * feedback;

        % Circular buffer write
        circularBuffer(bufferIndex, :) = outputSignal(n, :);
        bufferIndex = mod(bufferIndex, maxBufferSize) + 1;
    end

    % Normalize the output signal to prevent clipping
    outputSignal = outputSignal / max(abs(outputSignal));

    % Plot the output wave
    subplot(2, 1, 2);
    plot(t, outputSignal);
    title('Output Wave (Flanger Effect with Feedback)');
    xlabel('Time (s)');
    ylabel('Amplitude');

    % Save the output wave to a new file
    audiowrite(outputWavefile, outputSignal, Fs);
end