| 1 | from numpy import * |
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| 2 | |
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| 3 | __all__ = ['gabor_fn'] |
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| 4 | |
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| 5 | def gabor_fn(sigma_x,sigma_y,theta,lambda_,psi,gamma,width=None, height=None): |
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| 6 | ''' |
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| 7 | Gabor function, adapted from Wikipedia's matlab code |
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| 8 | ''' |
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| 9 | if width is None: |
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| 10 | sz_x = 6*sigma_x |
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| 11 | width = sz_x |
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| 12 | else: |
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| 13 | sz_x = width |
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| 14 | if sz_x%2==0: |
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| 15 | sz_x = sz_x+1 |
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| 16 | |
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| 17 | if height is None: |
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| 18 | sz_y= 6*sigma_y |
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| 19 | height = sz_y |
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| 20 | else: |
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| 21 | sz_y = height |
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| 22 | if sz_y%2==0: |
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| 23 | sz_y = sz_y+1 |
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| 24 | |
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| 25 | x,y = mgrid[-int(sz_x/2):int(sz_x/2)+1,int(-sz_y/2):int(sz_y/2)+1] |
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| 26 | |
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| 27 | # Rotation |
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| 28 | x_theta = x*cos(theta)+y*sin(theta) |
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| 29 | y_theta = -x*sin(theta)+y*cos(theta) |
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| 30 | |
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| 31 | gb = exp(-.5*(x_theta**2/sigma_x**2+gamma**2*y_theta**2/sigma_y**2))*cos(2*pi/lambda_*x_theta+psi) |
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| 32 | return gb[0:width,0:height] |
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| 33 | |
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| 34 | if __name__=='__main__': |
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| 35 | import pylab |
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| 36 | theta = pi/4 |
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| 37 | gb = gabor_fn(100.,100.,theta,300.,0.,0.8,500,520) |
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| 38 | print gb.shape |
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| 39 | pylab.gray() |
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| 40 | pylab.imshow(gb) |
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| 41 | pylab.colorbar() |
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| 42 | pylab.show() |
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