(4 intermediate revisions by the same user not shown)
Line 8: Line 8:
 
  N6 = sin(2*pi*554.3652618*[0:0.0001:0.5]);      %Csharp eigth
 
  N6 = sin(2*pi*554.3652618*[0:0.0001:0.5]);      %Csharp eigth
 
  N7 = sin(2*pi*523.2511306*[0:0.0001:2]);        %C half
 
  N7 = sin(2*pi*523.2511306*[0:0.0001:2]);        %C half
+
 
 
  rest = [0:0.0001:2.5];                        %rest half and an eigth
 
  rest = [0:0.0001:2.5];                        %rest half and an eigth
 +
 +
% smoke on the water (part a):
 +
tune = [N1 N2 N3 N4 N5 N6 N7 N1 N2 N3 N2 N1 rest];
 +
wavwrite(0.02*tune, 18667, 'question1a.wav');
 
   
 
   
  %smoke on the water (part a):
+
  % twice as fast (part b):
  tune = [N1 N2 N3 N4 N5 N6 N7 N1 N2 N3 N2 N1 rest];  
+
  wavwrite(0.02*tune, 37333, 'question1b.wav');
   
+
 
 +
  % y(t) = x(2t)  (part c):
 
  newtune = [1:1:(length(tune)/2)];
 
  newtune = [1:1:(length(tune)/2)];
% newtune(t) = tune(2t)
 
 
  for i=1:(length(tune)/2)
 
  for i=1:(length(tune)/2)
 
     newtune(1,i) = tune(1,2*i);
 
     newtune(1,i) = tune(1,2*i);
 
  end
 
  end
+
  wavwrite(0.02*newtune, 18667, 'question1c.wav');
%all three parts:
+
alltunes = [tune newtune newtune];
+
+
  wavwrite(0.02*alltunes, 18667, 'question1.wav');
+
 
   
 
   
  
  
 
+
  Sound files:  [[Media:question1a.wav]]
  Sound file:  [[Media:Example.ogg]]
+
              [[Media:question1b.wav]]
 +
              [[Media:question1c.wav]]
  
 
   
 
   
Line 42: Line 43:
  
  
 
+
  Sound file:  [[Media:question2.wav]]
  Sound file:  [[Media:Example.ogg]]
+
  
 
  1. The repeated phrase was "number nine".
 
  1. The repeated phrase was "number nine".
 
  2. I couldn't hear any message in the reversed version.
 
  2. I couldn't hear any message in the reversed version.

Latest revision as of 20:18, 14 January 2011

% Question 1:
function[] = question1()
N1 = sin(2*pi*391.995436*[0:0.0001:1]);         %G quarter note
N2 = sin(2*pi*466.1637615*[0:0.0001:1]);        %Bflat quarter
N3 = sin(2*pi*523.2511306*[0:0.0001:1.5]);      %C dotted quarter
N4 = sin(2*pi*391.995436*[0:0.0001:1]);         %G quarter
N5 = sin(2*pi*466.1637615*[0:0.0001:1]);        %Bflat quarter
N6 = sin(2*pi*554.3652618*[0:0.0001:0.5]);      %Csharp eigth
N7 = sin(2*pi*523.2511306*[0:0.0001:2]);        %C half
rest = [0:0.0001:2.5];                         %rest half and an eigth
% smoke on the water (part a):
tune = [N1 N2 N3 N4 N5 N6 N7 N1 N2 N3 N2 N1 rest];
wavwrite(0.02*tune, 18667, 'question1a.wav'); 

% twice as fast (part b):
wavwrite(0.02*tune, 37333, 'question1b.wav');
% y(t) = x(2t)  (part c):
newtune = [1:1:(length(tune)/2)];
for i=1:(length(tune)/2)
    newtune(1,i) = tune(1,2*i);
end
wavwrite(0.02*newtune, 18667, 'question1c.wav');


Sound files:  Media:question1a.wav
              Media:question1b.wav
              Media:question1c.wav



% Question 2:
function[] = question2()
[y, Fs] = wavread('Beatles.wav');
y = flipud(y);
wavwrite(y, Fs, 'question2.wav');


Sound file:  Media:question2.wav
1. The repeated phrase was "number nine".
2. I couldn't hear any message in the reversed version.

Alumni Liaison

BSEE 2004, current Ph.D. student researching signal and image processing.

Landis Huffman