Reorganized Into Folders

src/NotWorking/Daniel_Doan_convolution.m

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+function x = Daniel_Doan_convolution(f,h)
+    %input: two 1d arrays representing two sound signals in the time domain
+    %output: the convolution of the two waves, which is the inverse FT of
+    %FT(f)*FT(h)
+    %author: Daniel Doan
+
+    %padding to ensure the entire convolution is calculated
+    pad = length(f) + length(h) - 1;
+    %take FT of f
+    F = fft(f, pad);
+    %take FT of h
+    H = fft(h, pad);
+    %multiply the two FTs
+    X = F .* H;
+    %take inverse FT of the product
+    x = ifft(X);
+end

src/NotWorking/add_sine.m

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+function x = add_sine(amplitude, fundamental, harmonics, fs, duration)
+% ADD_SINE: Additive sine wave synthesis
+
+%CONTRIBUTORS:
+%Benjamin Liou: Original author
+
+% DOCUMENTATION:
+% harmonics should ideally be a 1D matrix of:
+    % overtones: positive integers
+    % undertones: 1/ positive integers
+    % example: [1/2, 1, 2, 3]
+    % NOTE: pitch of the fundamental frequency will still be perceived even
+        % when the fundamental itself is missing. ex. [4,5,6]
+    
+% NOTE: it seems like when MATLAB's built in sound() takes in values,
+    % magnitudes over 1 get distorted.
+    
+    
+    
+    % initialize local variables from input arguments
+    n = fs * duration; % number of samples (length of matrix)
+    
+    % initialize a one dimensional zero matrix to be populated
+    x = zeros(1, n);
+    
+    % populate matrix by adding sine waves
+    for harmonic = harmonics
+        x = x + generate_sine(1, fundamental * harmonic, 0, fs, duration);
+    end
+    
+    % scale to amplitude
+    scalar = max(abs(x));
+    x = x / scalar * amplitude;
+end

src/NotWorking/fade_in.m

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+function output = fade_in(input, time)
+    % Creates a fade-in sound effect that lasts a given
+    % time parameter of the input sound signal
+    % By Yalu Ouyang
+    
+
+    % input: a 1D array that represents the sound signal in the time domain
+    % time: how long the fade in effect should last
+    % Shouldn't be longer than the input signal (in which case the function
+    % treats it as the duration of the signal)
+    % Returns modified signal in the time domain (output).
+    
+    len = length(input);
+    
+    % if time parameter longer than signal, treat time as
+    % the duration of original signal
+    if time > len
+        time = len
+    end
+
+    % set multiplier as 1D array
+    % fade in effect: from no volume to full volume of signal
+    multiplier = (1 : time) / time;
+
+    % the resulting fade-in output  
+    output = input .* multiplier;
+end
+
+% This is useful for making videos, specifically the intro part 

src/NotWorking/fade_out.m

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+function output = fade_out(input, time)
+    % Creates a fade-out sound effect that lasts a given
+    % time parameter of the input sound signal
+    % By Yalu Ouyang
+    
+    % input: a 1D array that represents the sound signal in the time domain
+    % time: how long the fade out effect should last
+    % Shouldn't be longer than the input signal 
+    % (in which case the function treats it as the duration of the signal)
+    % Returns modified signal in the time domain (output).
+    
+    len = length(input);
+    
+    % if time parameter longer than signal, treat time as
+    % the duration of original signal
+    if time > len
+        time = len
+    end
+
+    % set multiplier as 1D array
+
+    multiplier = (1 : time) / time;
+
+    % fade out effect: from full volume of signal to no volume
+    multiplier = flip(multiplier)
+
+    % the resulting fade-in output  
+    output = input .* multiplier;
+end
+
+
+% This is useful for creating videos, specifically the outro part