Difference between revisions of "HW1.2 Brian Thomas ECE301Fall2008mboutin" - Rhea

Latest revision as of 12:23, 4 September 2008

Matlab Script

Does Judas Priest have subliminal messages? I wrote a MATLAB script to find out:

% Brian Thomas (thomas34 _ nospam _ purdue _ edu)
% Sept. 4, 2008
% ECE301, HW#1.2
% Play a piece of music backwards, then slowly backwards

% Clear everything
clear; clc;

% Get music piece
[forwardData, sampleRate, bitsPerSample] = wavread('jpforward.wav');
datalen = length(forwardData);

% Preallocate space for backwardData.  We first will be reversing
% forwardData at normal speed. (x[n] -> x[-n])
backwardData = zeros(1,datalen);
for i = 1 : 1 : datalen
    backwardData(i) = forwardData(datalen - i + 1);
end
% Play the song
%wavplay(backwardData, sampleRate);
% Save song as a wav file (as this is being done remotely)
wavwrite(backwardData, sampleRate, bitsPerSample, 'jpbackward.wav');

% Preallocate space for backwardData2.  We will be reversing
% forwardData and playing it at half speed. (x[n] -> x[-0.5n])
backwardData2 = zeros(1,datalen*2);
for i = 1 : 1 : datalen
    backwardData2(2*i) = forwardData(datalen - i + 1);
end
% Play the song
%wavplay(backwardData2, sampleRate);
% Save song as a wav file (as this is being done remotely)
wavwrite(backwardData2, sampleRate, bitsPerSample, 'jpbackward_slow.wav');

Results

Two wav files were obtained: normal speed and slow speed.

I could not find any definite hidden messages. It seemed like he was saying "the fire of the night", but that's at most a guess.