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[[Media:Normal_Song.wav]]
 
[[Media:Normal_Song.wav]]
 
[[Media:Twice_as_fast.wav]]
 
[[Media:Twice_as_fast.wav]]
 +
[[Media:Transformation_x(2t).wav]]
 
%Megha Reddy
 
%Megha Reddy
 
%ECE 301
 
%ECE 301

Revision as of 08:39, 19 January 2011

Media:Normal_Song.wav Media:Twice_as_fast.wav Media:Transformation_x(2t).wav %Megha Reddy %ECE 301

clear clc %Part 1 G_freq = 391.995; Bflat_freq = 466.164; C_freq = 523.251; Dflat_freq = 544.365;

bpm = 112; %number of beats per minute beats_per_sec = bpm/60; %number of beats per second rev_bps = 1/beats_per_sec; %calculates the time for each beat

delta = 0.00005;

Q = 0:delta:1*rev_bps; %duration of a quarter note E = 0:delta:0.5*rev_bps; %duration of an eight note H = 0:delta:2*rev_bps; %duration of a half note DQ = 0:delta:1.5*rev_bps; %duration of a dotted quarter note

G_Q = sin(2*pi*G_freq*Q); %calculates a G quarter note Bflat_Q = sin(2*pi*Bflat_freq*Q); %calculates a B flat quarter note Cdot = sin(2*pi*C_freq*DQ); %calculates a C dotted quarter note Dflat_E = sin(2*pi*Dflat_freq*E); %calculates a D flat eighth note C_H = sin(2*pi*C_freq*H); %calculates a C half note rest_E = zeros(E/delta,1); %calculates an eighth rest rest_H = zeros(H/delta,1); % calculates a half rest

%puts the notes in an array to be able to play the song song = [G_Q,Bflat_Q,Cdot,G_Q,Bflat_Q,Dflat_E,C_H,G_Q,Bflat_Q,Cdot,Bflat_Q,G_Q,rest_E,rest_H]; sound(song,1/delta);

%plays song two times faster sound(song,2/delta);

%doubles the time interval for each note newQ = 2*Q; newE = 2*E; newH = 2*H; newDQ = 2*DQ;

G_Q = sin(2*pi*G_freq*newQ); Bflat_Q = sin(2*pi*Bflat_freq*newQ); Cdot = sin(2*pi*C_freq*newDQ); Dflat_E = sin(2*pi*Dflat_freq*newE); C_H = sin(2*pi*C_freq*newH); rest_E = zeros(E/delta,1); rest_H = zeros(H/delta,1);

%plays the song with the new time interval song = [G_Q,Bflat_Q,Cdot,G_Q,Bflat_Q,Dflat_E,C_H,G_Q,Bflat_Q,Cdot,Bflat_Q,G_Q,rest_E,rest_H]; sound(song,1/delta);

clear clc

%Part 2 [song,Fs] = wavread('Beatles.wav'); %reads the given file and stores it in an array

song_rev = flipud(song); %flips the array

sound(song_rev,Fs); %plays the reversed song

%The reverse song does contain it message, the words are not clear but it %says "turn me on dead man"

Alumni Liaison

Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett