using argv[0] represent binary executable files' name in help() function

in sample codes instead of cpp files' name.

samples/cpp/detect_mser.cpp

@@ -34,13 +34,13 @@ using namespace std;
 using namespace cv;
 
 
-static void help()
+static void help(char** argv)
 {
     cout << "\nThis program demonstrates how to use MSER to detect extremal regions\n"
-        "Usage:\n"
-        "  ./detect_mser <image1(without parameter a synthetic image is used as default)>\n"
-        "Press esc key when image window is active to change descriptor parameter\n"
-        "Press 2, 8, 4, 6, +, -, or 5 keys in openGL windows to change view or use mouse\n";
+            "Usage:\n"
+         << argv[0] << " <image1(without parameter a synthetic image is used as default)>\n"
+            "Press esc key when image window is active to change descriptor parameter\n"
+            "Press 2, 8, 4, 6, +, -, or 5 keys in openGL windows to change view or use mouse\n";
 }
 
 struct MSERParams
@@ -405,7 +405,7 @@ int main(int argc, char *argv[])
     cv::CommandLineParser parser(argc, argv, "{ help h | | }{ @input | | }");
     if (parser.has("help"))
     {
-        help();
+        help(argv);
         return 0;
     }
 
@@ -431,7 +431,7 @@ int main(int argc, char *argv[])
     for (int i = 0; i<=numeric_limits<uint16_t>::max(); i++)
         palette.push_back(Vec3b((uchar)rand(), (uchar)rand(), (uchar)rand()));
 
-    help();
+    help(argv);
 
     MSERParams params;