"atomic bomb" commit. Reorganized OpenCV directory structure

samples/python/fitellipse.py

@@ -0,0 +1,105 @@
+#!/usr/bin/python
+"""
+This program is a demonstration of ellipse fitting.
+
+Trackbar controls threshold parameter.
+
+Gray lines are contours.  Colored lines are fit ellipses.
+
+Original C implementation by:  Denis Burenkov.
+Python implementation by: Roman Stanchak, James Bowman
+"""
+
+import sys
+import urllib2
+import random
+import cv
+
+def contour_iterator(contour):
+    while contour:
+        yield contour
+        contour = contour.h_next()
+
+class FitEllipse:
+
+    def __init__(self, source_image, slider_pos):
+        self.source_image = source_image
+        cv.CreateTrackbar("Threshold", "Result", slider_pos, 255, self.process_image)
+        self.process_image(slider_pos)
+
+    def process_image(self, slider_pos): 
+        """
+        This function finds contours, draws them and their approximation by ellipses.
+        """
+        stor = cv.CreateMemStorage()
+        
+        # Create the destination images
+        image02 = cv.CloneImage(self.source_image)
+        cv.Zero(image02)
+        image04 = cv.CreateImage(cv.GetSize(self.source_image), cv.IPL_DEPTH_8U, 3)
+        cv.Zero(image04)
+
+        # Threshold the source image. This needful for cv.FindContours().
+        cv.Threshold(self.source_image, image02, slider_pos, 255, cv.CV_THRESH_BINARY)
+
+        # Find all contours.
+        cont = cv.FindContours(image02,
+            stor,
+            cv.CV_RETR_LIST,
+            cv.CV_CHAIN_APPROX_NONE,
+            (0, 0))
+
+        for c in contour_iterator(cont):
+            # Number of points must be more than or equal to 6 for cv.FitEllipse2
+            if len(c) >= 6:
+                # Copy the contour into an array of (x,y)s
+                PointArray2D32f = cv.CreateMat(1, len(c), cv.CV_32FC2)
+                for (i, (x, y)) in enumerate(c):
+                    PointArray2D32f[0, i] = (x, y)
+                
+                # Draw the current contour in gray
+                gray = cv.CV_RGB(100, 100, 100)
+                cv.DrawContours(image04, c, gray, gray,0,1,8,(0,0))
+                
+                # Fits ellipse to current contour.
+                (center, size, angle) = cv.FitEllipse2(PointArray2D32f)
+                
+                # Convert ellipse data from float to integer representation.
+                center = (cv.Round(center[0]), cv.Round(center[1]))
+                size = (cv.Round(size[0] * 0.5), cv.Round(size[1] * 0.5))
+                angle = -angle
+                
+                # Draw ellipse in random color
+                color = cv.CV_RGB(random.randrange(256),random.randrange(256),random.randrange(256))
+                cv.Ellipse(image04, center, size,
+                          angle, 0, 360,
+                          color, 2, cv.CV_AA, 0)
+
+        # Show image. HighGUI use.
+        cv.ShowImage( "Result", image04 )
+
+
+if __name__ == '__main__':
+    if len(sys.argv) > 1:
+        source_image = cv.LoadImage(sys.argv[1], cv.CV_LOAD_IMAGE_GRAYSCALE)
+    else:
+        url = 'https://code.ros.org/svn/opencv/trunk/opencv/samples/c/stuff.jpg'
+        filedata = urllib2.urlopen(url).read()
+        imagefiledata = cv.CreateMatHeader(1, len(filedata), cv.CV_8UC1)
+        cv.SetData(imagefiledata, filedata, len(filedata))
+        source_image = cv.DecodeImage(imagefiledata, cv.CV_LOAD_IMAGE_GRAYSCALE)
+    
+    # Create windows.
+    cv.NamedWindow("Source", 1)
+    cv.NamedWindow("Result", 1)
+
+    # Show the image.
+    cv.ShowImage("Source", source_image)
+
+    fe = FitEllipse(source_image, 70)
+
+    print "Press any key to exit"
+    cv.WaitKey(0)
+
+    cv.DestroyWindow("Source")
+    cv.DestroyWindow("Result")