In [361]:

    

# Kurt Kaminski
# MAT201A HW2: Sound to Image
#
# This program loops through a sound and places the samples
# into an image line-by-line, then moves the pixels to arrange
# them in an archimedean spiral. In this case, the sound is
# data representing the precession index of Earth over 10 million
# years. The sound is one second long, each sample represents
# 200 years.
#
# en.wikipedia.org/wiki/Milankovitch_cycles

%pylab inline
from scipy.io import wavfile;
import wave;
from __future__ import division;

sr,sample = wavfile.read('precessionindex_LFO.wav');
print 'Sample size: ', sample.size;

x = 300;
y = int(sample.size/x);
newimg = sample[:x*y].reshape(y, x);

# print (x, y);
# imshow(newimg, cmap=cm.BrBG);

sortedImage = arange(newimg.size).reshape(y,x);  
it = nditer(newimg, flags=['multi_index']);  #iterator

a = [0];
b = [0]; 
j = 0;   #current step

while not it.finished: 
    
#     print it.index, "=", it[0];

    i0 = it.multi_index[0];
    i1 = it.multi_index[1];
        
    o = (j/newimg.size)*pi*50;  #theta
    q = 2;  #multiplier

    s = (y/2) + ( cos((o*q) + o)) * o * .5;
    t = (x/2) + ( sin((o*q) + o)) * o * .5 ;
    
    a.append( s );
    b.append( t );
    
    if s < y and t < x:
        sortedImage[int(s), int(t)] = it[0];
    
    j+=1;
    it.iternext();
    
gcf().set_figheight(10);
gcf().set_figwidth(10);
imshow(sortedImage, cmap=cm.BrBG, interpolation='none');


    

    




Populating the interactive namespace from numpy and matplotlib
Sample size:  50001






    




WARNING: pylab import has clobbered these variables: ['sample', 'i0']
`%matplotlib` prevents importing * from pylab and numpy






    

In [362]:

    

# utility
print(min(a), max(a))
print(min(b), max(b))
print(len(a), len(b))


    

    




(0, 161.53472305173727)
(0, 227.75441817634737)
(49801, 49801)

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