added docs and minor program changes

samples/cpp/segment_objects.cpp

@@ -6,6 +6,15 @@
 
 using namespace cv;
 
+void help()
+{
+	printf("\n"
+			"This program demonstrated a simple method of connected components clean up of background subtraction\n"
+			"When the program starts, it begins learning the background. You can toggle background learning on and off\n"
+			"by hitting the space bar.\n"
+			"Call\n"
+			"./segment_objects [video file, else it reads camera 0]\n\n");
+}
 
 void refineSegments(const Mat& img, Mat& mask, Mat& dst)
 {
@@ -52,6 +61,8 @@ int main(int argc, char** argv)
     VideoCapture cap;
     bool update_bg_model = true;
     
+    help();
+
     if( argc < 2 )
         cap.open(0);
     else
@@ -59,7 +70,7 @@ int main(int argc, char** argv)
     
     if( !cap.isOpened() )
     {
-        printf("can not open camera or video file\n");
+        printf("\nCan not open camera or video file\n");
         return -1;
     }
     
@@ -93,7 +104,10 @@ int main(int argc, char** argv)
         if( keycode == 27 )
             break;
         if( keycode == ' ' )
+        {
             update_bg_model = !update_bg_model;
+            printf("Learn background is in state = %d\n",update_bg_model);
+        }
     }
     
     return 0;