added chamfer matcher code and sample (contributed by Antonella Cascitelli, Marco Di Stefano and Stefano Fabri)

samples/cpp/chamfer.cpp

@@ -0,0 +1,48 @@
+#include <opencv2/imgproc/imgproc.hpp>
+#include <opencv2/highgui/highgui.hpp>
+#include <opencv2/contrib/contrib.hpp>
+
+#include <iostream>
+
+using namespace cv;
+using namespace std;
+
+int main( int argc, char** argv )
+{
+    if( argc != 1 && argc != 3 )
+    {
+        cout << "Usage: chamfer <image edge map> <template edge map>\n";
+        return 0;
+    }
+    Mat img = imread(argc == 3 ? argv[1] : "logo_in_clutter.png", 0);
+    Mat cimg;
+    cvtColor(img, cimg, CV_GRAY2BGR);
+    Mat tpl = imread(argc == 3 ? argv[2] : "logo.png", 0);
+    
+    // if the image and the template are not edge maps but normal grayscale images,
+    // you might want to uncomment the lines below to produce the maps. You can also
+    // run Sobel instead of Canny.
+    
+    // Canny(img, img, 5, 50, 3);
+    // Canny(tpl, tpl, 5, 50, 3);
+    
+    vector<vector<Point> > results;
+    vector<float> costs;
+    int best = chamerMatching( img, tpl, results, costs );
+    if( best < 0 )
+    {
+        cout << "not found;\n";
+        return 0;
+    }
+    
+    size_t i, n = results[best].size();
+    for( i = 0; i < n; i++ )
+    {
+        Point pt = results[best][i];
+        if( pt.inside(Rect(0, 0, cimg.cols, cimg.rows)) )
+           cimg.at<Vec3b>(pt) = Vec3b(0, 255, 0);
+    }
+    imshow("result", cimg);
+    waitKey();
+    return 0;
+}