Adding Harris matching example.

examples/ch2_harris_matching.py

@@ -0,0 +1,34 @@
+from pylab import *
+from numpy import *
+from PIL import Image
+
+from PCV.localdescriptors import harris
+from PCV.tools.imtools import imresize
+
+"""
+This is the Harris point matching example in Figure 2-2.
+"""
+
+im1 = array(Image.open("../data/crans_1_small.jpg").convert("L"))
+im2 = array(Image.open("../data/crans_2_small.jpg").convert("L"))
+
+# resize to make matching faster
+im1 = imresize(im1,(im1.shape[1]/2,im1.shape[0]/2))
+im2 = imresize(im2,(im2.shape[1]/2,im2.shape[0]/2))
+
+wid = 5
+harrisim = harris.compute_harris_response(im1,5) 
+filtered_coords1 = harris.get_harris_points(harrisim,wid+1) 
+d1 = harris.get_descriptors(im1,filtered_coords1,wid)
+
+harrisim = harris.compute_harris_response(im2,5) 
+filtered_coords2 = harris.get_harris_points(harrisim,wid+1) 
+d2 = harris.get_descriptors(im2,filtered_coords2,wid)
+
+print 'starting matching'
+matches = harris.match_twosided(d1,d2)
+
+figure()
+gray() 
+harris.plot_matches(im1,im2,filtered_coords1,filtered_coords2,matches) 
+show()