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