% Sachin Santhakumar % ECE 301 % HW 01 Problem 01 % Playing Music % 01/19/2011
clear; clc;
% beats per second bps = 112/60; % seconds per beat beat_time = bps^-1;
% Length of time for each entry in the sound array delta = 0.00005;
% Note lengths quarter = 0:delta:beat_time; half = 0:delta:beat_time*2; dotquart = 0:delta:beat_time*(3/2); eighth = 0:delta:beat_time*(1/2);
% Note frequencies freqG = 391.995; freqBf = 466.164; freqC = 523.251; freqDf = 554.365;
% Construction of the signal of all the required notes GQ = sin(2*pi*freqG*quarter); BfQ = sin(2*pi*freqBf*quarter); CDq = sin(2*pi*freqC*dotquart); DfE = sin(2*pi*freqDf*eighth); CH = sin(2*pi*freqC*half); CDq = sin(2*pi*freqC*dotquart); Erest = zeros((eighth/delta),1); Hrest = zeros((half/delta),1);
% Signal for the song X = [GQ,BfQ,CDq,GQ,BfQ,DfE,CH,GQ,BfQ,CDq,BfQ,GQ,Erest,Hrest];
% Plays wav file wavplay(X,1/delta);
% Plays wav file twice as fast wavplay(X,(2/delta));
% Transformation of y(t) = x(2t); GQ = sin(4*pi*freqG*quarter); BfQ = sin(4*pi*freqBf*quarter); CDq = sin(4*pi*freqC*dotquart); DfE = sin(4*pi*freqDf*eighth); CH = sin(4*pi*freqC*half); CDq = sin(4*pi*freqC*dotquart); Erest = zeros((2*eighth/delta),1); Hrest = zeros((2*half/delta),1);
Y = [GQ,BfQ,CDq,GQ,BfQ,DfE,CH,GQ,BfQ,CDq,BfQ,GQ,Erest,Hrest];
% Plays modified wav file wavplay(Y,1/delta);
% Sachin Santhakumar % ECE 301 % HW 01 Problem 02 % Hidden Backward Message % 01/19/2011
clear; clc;
% Reads in wav file [Y, f] = wavread ('Beatles.wav');
Yrev = flipud (Y); % Plays backwards wav file wavplay(Yrev,f);
% Forwards the sound clip seems to say "Number Nine" % Backwards the sound clip seems to say "Turn Me On Dead Man"
