137 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			137 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			Python
		
	
	
		
			Executable File
		
	
	
	
	
| #! /usr/bin/env python
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| 
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| print "OpenCV Python version of contours"
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| 
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| # import the necessary things for OpenCV
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| import cv2.cv as cv
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| 
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| # some default constants
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| _SIZE = 500
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| _DEFAULT_LEVEL = 3
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| 
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| # definition of some colors
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| _red =  (0, 0, 255, 0);
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| _green =  (0, 255, 0, 0);
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| _white = cv.RealScalar (255)
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| _black = cv.RealScalar (0)
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| 
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| # the callback on the trackbar, to set the level of contours we want
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| # to display
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| def on_trackbar (position):
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| 
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|     # create the image for putting in it the founded contours
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|     contours_image = cv.CreateImage ( (_SIZE, _SIZE), 8, 3)
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| 
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|     # compute the real level of display, given the current position
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|     levels = position - 3
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| 
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|     # initialisation
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|     _contours = contours
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| 
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|     if levels <= 0:
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|         # zero or negative value
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|         # => get to the nearest face to make it look more funny
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|         _contours = contours.h_next().h_next().h_next()
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| 
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|     # first, clear the image where we will draw contours
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|     cv.SetZero (contours_image)
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| 
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|     # draw contours in red and green
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|     cv.DrawContours (contours_image, _contours,
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|                        _red, _green,
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|                        levels, 3, cv.CV_AA,
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|                         (0, 0))
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| 
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|     # finally, show the image
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|     cv.ShowImage ("contours", contours_image)
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| 
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| if __name__ == '__main__':
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| 
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|     # create the image where we want to display results
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|     image = cv.CreateImage ( (_SIZE, _SIZE), 8, 1)
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| 
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|     # start with an empty image
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|     cv.SetZero (image)
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| 
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|     # draw the original picture
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|     for i in range (6):
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|         dx = (i % 2) * 250 - 30
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|         dy = (i / 2) * 150
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| 
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|         cv.Ellipse (image,
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|                        (dx + 150, dy + 100),
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|                        (100, 70),
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|                       0, 0, 360, _white, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 115, dy + 70),
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|                        (30, 20),
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|                       0, 0, 360, _black, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 185, dy + 70),
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|                        (30, 20),
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|                       0, 0, 360, _black, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 115, dy + 70),
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|                        (15, 15),
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|                       0, 0, 360, _white, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 185, dy + 70),
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|                        (15, 15),
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|                       0, 0, 360, _white, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 115, dy + 70),
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|                        (5, 5),
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|                       0, 0, 360, _black, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 185, dy + 70),
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|                        (5, 5),
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|                       0, 0, 360, _black, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 150, dy + 100),
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|                        (10, 5),
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|                       0, 0, 360, _black, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 150, dy + 150),
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|                        (40, 10),
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|                       0, 0, 360, _black, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 27, dy + 100),
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|                        (20, 35),
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|                       0, 0, 360, _white, -1, 8, 0)
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|         cv.Ellipse (image,
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|                        (dx + 273, dy + 100),
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|                        (20, 35),
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|                       0, 0, 360, _white, -1, 8, 0)
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| 
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|     # create window and display the original picture in it
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|     cv.NamedWindow ("image", 1)
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|     cv.ShowImage ("image", image)
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| 
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|     # create the storage area
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|     storage = cv.CreateMemStorage (0)
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| 
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|     # find the contours
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|     contours = cv.FindContours(image,
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|                                storage,
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|                                cv.CV_RETR_TREE,
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|                                cv.CV_CHAIN_APPROX_SIMPLE,
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|                                (0,0))
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| 
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|     # comment this out if you do not want approximation
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|     contours = cv.ApproxPoly (contours,
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|                                 storage,
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|                                 cv.CV_POLY_APPROX_DP, 3, 1)
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| 
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|     # create the window for the contours
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|     cv.NamedWindow ("contours", 1)
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| 
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|     # create the trackbar, to enable the change of the displayed level
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|     cv.CreateTrackbar ("levels+3", "contours", 3, 7, on_trackbar)
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| 
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|     # call one time the callback, so we will have the 1st display done
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|     on_trackbar (_DEFAULT_LEVEL)
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| 
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|     # wait a key pressed to end
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|     cv.WaitKey (0)
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|     cv.DestroyAllWindows()
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