Update to 2.0.0 tree from current Fremantle build

[opencv] / samples / swig_python / fitellipse.py

diff --git a/samples/swig_python/fitellipse.py b/samples/swig_python/fitellipse.py
new file mode 100755 (executable)
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+++ b/samples/swig_python/fitellipse.py
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+#!/usr/bin/python
+"""
+This program is demonstration for ellipse fitting. Program finds 
+contours and approximate it by ellipses.
+
+Trackbar specify threshold parametr.
+
+White lines is contours. Red lines is fitting ellipses.
+
+Original C implementation by:  Denis Burenkov.
+Python implementation by: Roman Stanchak
+"""
+
+import sys
+from opencv import cv
+from opencv import highgui
+
+image02 = None
+image03 = None
+image04 = None
+
+def process_image( slider_pos ): 
+    """
+    Define trackbar callback functon. This function find contours,
+    draw it and approximate it by ellipses.
+    """
+    stor = cv.cvCreateMemStorage(0);
+    
+    # Threshold the source image. This needful for cv.cvFindContours().
+    cv.cvThreshold( image03, image02, slider_pos, 255, cv.CV_THRESH_BINARY );
+    
+    # Find all contours.
+    nb_contours, cont = cv.cvFindContours (image02,
+            stor,
+            cv.sizeof_CvContour,
+            cv.CV_RETR_LIST,
+            cv.CV_CHAIN_APPROX_NONE,
+            cv.cvPoint (0,0))
+    
+    # Clear images. IPL use.
+    cv.cvZero(image02);
+    cv.cvZero(image04);
+    
+    # This cycle draw all contours and approximate it by ellipses.
+    for c in cont.hrange():
+        count = c.total; # This is number point in contour
+
+        # Number point must be more than or equal to 6 (for cv.cvFitEllipse_32f).        
+        if( count < 6 ):
+            continue;
+        
+        # Alloc memory for contour point set.    
+        PointArray = cv.cvCreateMat(1, count, cv.CV_32SC2)
+        PointArray2D32f= cv.cvCreateMat( 1, count, cv.CV_32FC2)
+        
+        # Get contour point set.
+        cv.cvCvtSeqToArray(c, PointArray, cv.cvSlice(0, cv.CV_WHOLE_SEQ_END_INDEX));
+        
+        # Convert CvPoint set to CvBox2D32f set.
+        cv.cvConvert( PointArray, PointArray2D32f )
+        
+        box = cv.CvBox2D()
+
+        # Fits ellipse to current contour.
+        box = cv.cvFitEllipse2(PointArray2D32f);
+        
+        # Draw current contour.
+        cv.cvDrawContours(image04, c, cv.CV_RGB(255,255,255), cv.CV_RGB(255,255,255),0,1,8,cv.cvPoint(0,0));
+        
+        # Convert ellipse data from float to integer representation.
+        center = cv.CvPoint()
+        size = cv.CvSize()
+        center.x = cv.cvRound(box.center.x);
+        center.y = cv.cvRound(box.center.y);
+        size.width = cv.cvRound(box.size.width*0.5);
+        size.height = cv.cvRound(box.size.height*0.5);
+        box.angle = -box.angle;
+        
+        # Draw ellipse.
+        cv.cvEllipse(image04, center, size,
+                  box.angle, 0, 360,
+                  cv.CV_RGB(0,0,255), 1, cv.CV_AA, 0);
+    
+    # Show image. HighGUI use.
+    highgui.cvShowImage( "Result", image04 );
+
+
+if __name__ == '__main__':
+    argc = len(sys.argv)
+    filename = "../c/stuff.jpg"
+    if(argc == 2):
+        filename = sys.argv[1]
+    
+    slider_pos = 70
+
+    # load image and force it to be grayscale
+    image03 = highgui.cvLoadImage(filename, 0)
+    if not image03:
+        print "Could not load image " + filename
+        sys.exit(-1)
+
+    # Create the destination images
+    image02 = cv.cvCloneImage( image03 );
+    image04 = cv.cvCloneImage( image03 );
+
+    # Create windows.
+    highgui.cvNamedWindow("Source", 1);
+    highgui.cvNamedWindow("Result", 1);
+
+    # Show the image.
+    highgui.cvShowImage("Source", image03);
+
+    # Create toolbars. HighGUI use.
+    highgui.cvCreateTrackbar( "Threshold", "Result", slider_pos, 255, process_image );
+
+
+    process_image( 1 );
+
+    #Wait for a key stroke; the same function arranges events processing                
+    print "Press any key to exit"
+    highgui.cvWaitKey(0);
+
+    highgui.cvDestroyWindow("Source");
+    highgui.cvDestroyWindow("Result");
+