60 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable File
		
	
	
	
	
| #!/usr/bin/env python
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| 
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| import numpy as np
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| from numpy import random
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| import cv2
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| 
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| def make_gaussians(cluster_n, img_size):
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|     points = []
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|     ref_distrs = []
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|     for i in xrange(cluster_n):
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|         mean = (0.1 + 0.8*random.rand(2)) * img_size
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|         a = (random.rand(2, 2)-0.5)*img_size*0.1
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|         cov = np.dot(a.T, a) + img_size*0.05*np.eye(2)
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|         n = 100 + random.randint(900)
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|         pts = random.multivariate_normal(mean, cov, n)
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|         points.append( pts )
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|         ref_distrs.append( (mean, cov) )
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|     points = np.float32( np.vstack(points) )
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|     return points, ref_distrs
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| 
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| def draw_gaussain(img, mean, cov, color):
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|     x, y = np.int32(mean)
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|     w, u, vt = cv2.SVDecomp(cov)
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|     ang = np.arctan2(u[1, 0], u[0, 0])*(180/np.pi)
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|     s1, s2 = np.sqrt(w)*3.0
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|     cv2.ellipse(img, (x, y), (s1, s2), ang, 0, 360, color, 1, cv2.LINE_AA)
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| 
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| 
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| if __name__ == '__main__':
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|     cluster_n = 5
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|     img_size = 512
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| 
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|     print 'press any key to update distributions, ESC - exit\n'
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| 
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|     while True:
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|         print 'sampling distributions...'
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|         points, ref_distrs = make_gaussians(cluster_n, img_size)
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| 
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|         print 'EM (opencv) ...'
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|         em = cv2.EM(cluster_n, cv2.EM_COV_MAT_GENERIC)
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|         em.train(points)
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|         means = em.getMat('means')
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|         covs = em.getMatVector('covs')
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|         found_distrs = zip(means, covs)
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|         print 'ready!\n'
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| 
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|         img = np.zeros((img_size, img_size, 3), np.uint8)
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|         for x, y in np.int32(points):
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|             cv2.circle(img, (x, y), 1, (255, 255, 255), -1)
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|         for m, cov in ref_distrs:
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|             draw_gaussain(img, m, cov, (0, 255, 0))
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|         for m, cov in found_distrs:
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|             draw_gaussain(img, m, cov, (0, 0, 255))
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| 
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|         cv2.imshow('gaussian mixture', img)
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|         ch = 0xFF & cv2.waitKey(0)
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|         if ch == 27:
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|             break
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|     cv2.destroyAllWindows()
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