Hw1 ECE301S11 Krishna Jhajaria - Rhea

Krishna Jhajaria
ECE 301 Homework 1

1. Matlab Code


for X=1:3
    if X==2
        BPS=112/120;
    else
        BPS=112/60;
    end
    if X==3
        A4=440*2;
    else 
        A4=440;
    end
    
    Delta=.00005;
    One=0:Delta:BPS;
    Half=0:Delta:BPS/2;
    Quarter=0:Delta:BPS/4;
    Eighth=0:Delta:BPS/8;
    Dotted_Q=0:Delta:BPS*.375;
    G_Q = sin(2*pi*(2^(-1/6)*A4)*Quarter);
    Bf_Q = sin(2*pi*(2^(1/12)*A4)*Quarter);
    C_DQ = sin(2*pi*(2^(1/4)*A4)*Dotted_Q);
    Df_E = sin(2*pi*(2^(1/3)*A4)*Eighth);
    C_H = sin(2*pi*(2^(1/4)*A4)*Half);
    G_H = sin(2*pi*(2^(-1/6)*A4)*Half);
    notes=[G_Q, Bf_Q, C_DQ, G_Q, Bf_Q, Df_E, C_H, G_Q, Bf_Q, C_DQ, Bf_Q, G_Q];
    if X==1
        wavwrite(notes, 1/Delta, 'regular');
    elseif X==2
        wavwrite(notes, 1/Delta, 'fast');
    else
        wavwrite(notes, 1/Delta, 'high');
    end
    
end




2. Hidden Message

[Notes, Fs, Bits] = wavread('Beatles.wav');
Reverse = flipud(Notes);
wavwrite(Reverse,Fs, 'Beatles_Reverse');


The forward message is "Number 9"
The backward message is "Let me on Dead man"