60 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| #!/usr/bin/env python
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| 
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| # Python 2/3 compatibility
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| from __future__ import print_function
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| import sys
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| PY3 = sys.version_info[0] == 3
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| 
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| if PY3:
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|     xrange = range
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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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| from tests_common import NewOpenCVTests
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| 
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| class gaussian_mix_test(NewOpenCVTests):
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| 
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|     def test_gaussian_mix(self):
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| 
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|         np.random.seed(10)
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|         cluster_n = 5
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|         img_size = 512
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| 
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|         points, ref_distrs = make_gaussians(cluster_n, img_size)
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| 
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|         em = cv2.ml.EM_create()
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|         em.setClustersNumber(cluster_n)
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|         em.setCovarianceMatrixType(cv2.ml.EM_COV_MAT_GENERIC)
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|         em.trainEM(points)
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|         means = em.getMeans()
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|         covs = em.getCovs()  # Known bug: https://github.com/Itseez/opencv/pull/4232
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|         found_distrs = zip(means, covs)
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| 
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|         matches_count = 0
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| 
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|         meanEps = 0.05
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|         covEps = 0.1
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| 
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|         for i in range(cluster_n):
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|             for j in range(cluster_n):
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|                 if (cv2.norm(means[i] - ref_distrs[j][0], cv2.NORM_L2) / cv2.norm(ref_distrs[j][0], cv2.NORM_L2) < meanEps and
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|                     cv2.norm(covs[i] - ref_distrs[j][1], cv2.NORM_L2) / cv2.norm(ref_distrs[j][1], cv2.NORM_L2) < covEps):
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|                     matches_count += 1
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| 
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|         self.assertEqual(matches_count, cluster_n) | 
