HW1.2 Ben Laskowski ECE301Fall2008mboutin - Rhea

Lyrics

Unfortunately, I am unable to pick out any definite words. In the full-speed reversal, the word "suicide" might appear but I'm not entirely sure.

Wave Files

• Reverse, normal speed
• Reverse, two-thirds speed

MATLAB Code

% Ben Laskowski (blaskows@purdue.edu)
% September 5, 2008
% ECE301 Section 2 HW1
%
% This file is supposed to reverse and slow a wav file for extraction of
% alleged subliminal messages.

% Begin by clearing the output console and all memory.
clear;
clc;

%Open the wave file and get its length, sample size, and sampling rate
[data,fs,nbits]=wavread('jpforward.wav');

%Play the file once normally
disp('Playing the unaltered file...')
wavplay(data,fs);

%Reverse the file, play it, and write it out
Length=size(data);
MaxCount=Length(1);
reversedata=zeros(MaxCount,1);
for counter=MaxCount:-1:1
    reversedata(MaxCount-counter+1,1)=data(counter);
end
disp('Playing reverse at normal speed...');
wavplay(reversedata,fs);
wavwrite(reversedata,fs,nbits,'jpreverse.wav');

%To slow the original data, we can just write out the reversed data with
% a fraction of the correct sampling rate.
disp('Playing reverse at 67% speed...');
wavwrite(reversedata,fs/1.5,nbits,'jpreverseslow.wav');
wavplay(reversedata,fs/1.5);