Added MatchTemplate_Demo.cpp to tutorial sample code

samples/cpp/tutorial_code/Histograms_Matching/MatchTemplate_Demo.cpp

+/**
+ * @file MatchTemplate_Demo.cpp
+ * @brief Sample code to use the function MatchTemplate
+ * @author OpenCV team
+ */
+
+#include "opencv2/highgui/highgui.hpp"
+#include "opencv2/imgproc/imgproc.hpp"
+#include <iostream>
+#include <stdio.h>
+
+using namespace std;
+using namespace cv;
+
+/// Global Variables
+Mat img; Mat templ; Mat result;
+char* image_window = "Source Image";
+char* result_window = "Result window";
+
+int match_method;
+int max_Trackbar = 5;
+
+/// Function Headers
+void MatchingMethod( int, void* );
+
+/**
+ * @function main
+ */
+int main( int argc, char** argv )
+{
+  /// Load image and template
+  img = imread( argv[1], 1 );
+  templ = imread( argv[2], 1 );
+
+  /// Create windows
+  namedWindow( image_window, CV_WINDOW_AUTOSIZE );
+  namedWindow( result_window, CV_WINDOW_AUTOSIZE );
+  
+  /// Create Trackbar
+  char* trackbar_label = "Method: \n 0: SQDIFF \n 1: SQDIFF NORMED \n 2: TM CCORR \n 3: TM CCORR NORMED \n 4: TM COEFF \n 5: TM COEFF NORMED";
+  createTrackbar( trackbar_label, image_window, &match_method, max_Trackbar, MatchingMethod );
+
+  MatchingMethod( 0, 0 );
+
+  waitKey(0);
+  return 0;
+}
+
+/**
+ * @function MatchingMethod
+ * @brief Trackbar callback
+ */
+void MatchingMethod( int, void* )
+{
+  /// Source image to display
+  Mat img_display;
+  img.copyTo( img_display );
+ 
+  /// Create the result matrix
+  int result_cols =  img.cols - templ.cols + 1;
+  int result_rows = img.rows - templ.rows + 1;   
+  
+  result.create( result_cols, result_rows, CV_32FC1 );
+
+  /// Do the Matching and Normalize
+  matchTemplate( img, templ, result, match_method );
+  normalize( result, result, 0, 1, NORM_MINMAX, -1, Mat() );
+
+  /// Localizing the best match with minMaxLoc
+  double minVal; double maxVal; Point minLoc; Point maxLoc;
+  Point matchLoc;
+ 
+  minMaxLoc( result, &minVal, &maxVal, &minLoc, &maxLoc, Mat() );
+
+
+  /// For SQDIFF and SQDIFF_NORMED, the best matches are lower values. For all the other methods, the higher the better
+  if( match_method  == CV_TM_SQDIFF || match_method == CV_TM_SQDIFF_NORMED )
+    { matchLoc = minLoc; }
+  else  
+    { matchLoc = maxLoc; }
+
+  /// Show me what you got
+  rectangle( img_display, matchLoc, Point( matchLoc.x + templ.cols , matchLoc.y + templ.rows ), Scalar::all(0), 2, 8, 0 ); 
+  rectangle( result, matchLoc, Point( matchLoc.x + templ.cols , matchLoc.y + templ.rows ), Scalar::all(0), 2, 8, 0 ); 
+
+  imshow( image_window, img_display );
+  imshow( result_window, result );
+
+  return;
+}