moved distortion_filter,

generate_heartbeat,
to NotWorking

src/NotWorking/distortion_filter.m

@@ -0,0 +1,26 @@
+% An audio is distorted based on the value of HIGH. Nothing of a certain
+% threshold should be played above this constant, or they are simply clipped to this 
+% value. Inspired from Meghaj_Echo.m and epic_effect_schluep.m.
+% Author: Jason Liang
+
+function y = distortion_filter(x, HIGH)
+  len = length(X);
+  X = fft(x);
+  X = fftshift(X);
+  Y = zeros(1, len);
+  
+  for ind = 1:len
+    if (X(ind) > HIGH) 
+       Y(ind) = HIGH;
+    elseif (X(ind) < -HIGH)
+      Y(ind) = -HIGH;
+    else 
+      Y(ind) = X(ind);
+    end
+  end
+  
+  Y = fftshift(Y);
+  y = ifft(Y);
+  y = real(y);
+
+end

src/NotWorking/generate_heartbeat.m

@@ -0,0 +1,46 @@
+function x = generate_heartbeat(amplitude, frequency, phase, fs, duration, duty)
+% GENERATE_SINE: returns a matrix of sampled heart monitor wave
+
+% CONTRIBUTORS:
+% Alex Nguyen: Original Author
+% Conner Hsu: Reviewed Code and Assisted in polishing
+
+% DOCUMENTATION:
+% phase shift is in number of periods
+% fs is the sampling frequency: how many sample points per second
+% duration is time in seconds
+% duty cycle should be a number between 0 and 0.5.
+    % duty of 0 or less would return 0 for all sample points
+    % duty of 0.5 or less would return a heartbeat signal since there would be
+        % equal amount of space within 1 period to have the right and left sides be equal
+    % duty of greater than 0.5 but less than 1 would return a slope starting at that duty i.e.
+        % the left side but leaving little room to the right side
+    % duty of between 1 and 2 would give a sawtooth wave in the +amplitude.
+    % duty greater than 2 would return 0 for all sample points
+   
+
+    % initialize local variables from input arguments
+    n = fs * duration; % number of samples (length of matrix)
+    dt = 1 / fs; % sampling period: time between two sample points
+    
+    
+    % initialize a one dimensional zero matrix to be populated
+    x = zeros(1, n);
+    
+    % populate the matrix
+    for i = 1:n
+        t = i * dt; % time at the i'th sample
+        st = mod(frequency * t - phase, 1);
+
+        if (duty-(duty / 2) < st && st < duty)
+            slope = amplitude / duty;
+            intercept = -0.5 * amplitude;
+            x(i) = slope * st + intercept;
+        elseif (duty < st && st < duty+(duty / 2)) 
+            slope = amplitude / duty;
+            intercept = -amplitude;
+            x(i) = slope * st + (1.5 * intercept);
+        else
+            x(i) = 0;
+    end
+end