%Hw1 ECE301S11

%Bob Wujek


clc, clear


%%%%%Playing Music%%%%%


%Defining base variables

beat = 60/112;  %Defines length of each beat using 112 bpm

delta = .00005;  %Defines step size for the time variable

f_A = 440;  %Defines frequency of an A4 note


%Defining note lengths

Qnote = 0:delta:beat;  %Defines length of a quarter note

Hnote = 0:delta:beat*2;  %Defines length of a half note

Enote = 0:delta:beat/2;  %Defines length of an eighth note

DQnote = 0:delta:beat*3/2;  %Defines length of a dotted quarter note


%Defining notes in terms of A4 note and appropriate lengths

Q_G = sin(2*pi*2^(-2/12)*f_A*Qnote);  %Defines quarter G note

Q_Bflat = sin(2*pi*2^(1/12)*f_A*Qnote); %Defines quarter B flat note

DQ_C = sin(2*pi*2^(3/12)*f_A*DQnote);  %Defines dotted quarter C note

E_Dflat = sin(2*pi*2^(4/12)*f_A*Enote); %Defines eighth D flat note

H_C = sin(2*pi*2^(3/12)*f_A*Hnote);  %Defines half C note


%Defining transformed notes

nQ_G = sin(2*pi*2^(-2/12)*f_A*Qnote*2);  %Defines new quarter G note

nQ_Bflat = sin(2*pi*2^(1/12)*f_A*Qnote*2); %Defines new quarter B flat note

nDQ_C = sin(2*pi*2^(3/12)*f_A*DQnote*2);  %Defines new dotted quarter C note

nE_Dflat = sin(2*pi*2^(4/12)*f_A*Enote*2); %Defines new eighth D flat note

nH_C = sin(2*pi*2^(3/12)*f_A*Hnote*2);  %Defines new half C note


%Defining rests

E_rest = zeros(1,beat/delta/2); %Defines an eighth rest

H_rest = zeros(1,beat/delta*2); %Defines a half rest


%Arranging the notes in the correct order according to the provided score

Smoke_Water_1 = [Q_G, Q_Bflat, DQ_C, Q_G, Q_Bflat, E_Dflat, H_C, Q_G,...

   Q_Bflat, DQ_C, Q_Bflat, Q_G, E_rest, H_rest];   %The original score

Smoke_Water_2 = Smoke_Water_1;

Smoke_Water_3 = [nQ_G, nQ_Bflat, nDQ_C, nQ_G, nQ_Bflat, nE_Dflat, nH_C,...

   nQ_G, nQ_Bflat, nDQ_C, nQ_Bflat, nQ_G, E_rest, H_rest]; %The transformed score


%Playing the 3 songs

sound(Smoke_Water_1, 1/delta);  %Plays song at original tempo

sound(Smoke_Water_2, 2/delta);  %Plays song at doubled tempo

sound(Smoke_Water_3, 1/delta);  %Plays transformed song


%Creating wave files for each song

wavwrite(Smoke_Water_1, 1/delta, 'SmokeontheWater');

   %Writes original song to a wav file

wavwrite(Smoke_Water_2, 2/delta, 'SmokeontheWater2xfast');

   %Writes song at double speed to a wav file

wavwrite(Smoke_Water_3, 1/delta, 'SmokeontheWatertransformed');

   %Writes transformed song to a wav file


%%%%%Hidden Backward Message%%%%%


clc, clear


[Beatles, f] = wavread('Beatles.wav');  %Records the song into 'Beatles'


Backward_Song = flipud(Beatles);  %Records the song into 'Backward_Song'


sound(Backward_Song, f);  %Plays the song, 'Backward_Song'


wavwrite(Backward_Song, f, 'BackwardBeatlesSong');  %Writes the song to a wav file


%%%The song plays the phrase "Number Nine" repeatedly

%%%While played in reverse, the phrase seems to be "Turn Me On Dead Man"


Media:SmokeontheWater.wav


Media:SmokeontheWater2xfast.wav


Media:SmokeontheWatertransformed.wav


Media:BackwardBeatlesSong.wav

Alumni Liaison

Correspondence Chess Grandmaster and Purdue Alumni

Prof. Dan Fleetwood