some improvements on tutorials

samples/cpp/tutorial_code/xfeatures2D/LATCH_match.cpp

@@ -81,7 +81,7 @@ int main(void)
 
     Mat res;
     drawMatches(img1, inliers1, img2, inliers2, good_matches, res);
-    imwrite("../../samples/data/latch_res.png", res);
+    imwrite("latch_result.png", res);
 
 
     double inlier_ratio = inliers1.size() * 1.0 / matched1.size();
@@ -93,6 +93,10 @@ int main(void)
     cout << "# Inliers:                            \t" << inliers1.size() << endl;
     cout << "# Inliers Ratio:                      \t" << inlier_ratio << endl;
     cout << endl;
+
+    imshow("result", res);
+    waitKey();
+
     return 0;
 }