Added reST tutorials for Contours (6 in imgproc) and for Corner Detection (4 in features2D) + links in conf.py

doc/tutorials/imgproc/shapedescriptors/bounding_rotated_ellipses/bounding_rotated_ellipses.rst

@@ -0,0 +1,128 @@
+.. _bounding_rotated_ellipses:
+
+
+Creating Bounding rotated boxes and ellipses for contours
+**********************************************************
+
+Goal
+=====
+
+In this tutorial you will learn how to:
+
+.. container:: enumeratevisibleitemswithsquare
+
+   * Use the OpenCV function :min_area_rect:`minAreaRect <>` 
+   * Use the OpenCV function :fit_ellipse:`fitEllipse <>`
+           
+
+Theory
+======
+
+Code
+====
+
+This tutorial code's is shown lines below. You can also download it from `here <https://code.ros.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ShapeDescriptors/generalContours_demo2.cpp>`_
+
+.. code-block:: cpp 
+
+   #include "opencv2/highgui/highgui.hpp"
+   #include "opencv2/imgproc/imgproc.hpp"
+   #include <iostream>
+   #include <stdio.h>
+   #include <stdlib.h>
+
+   using namespace cv;
+   using namespace std;
+
+   Mat src; Mat src_gray;
+   int thresh = 100;
+   int max_thresh = 255;
+   RNG rng(12345);
+
+   /// Function header
+   void thresh_callback(int, void* );
+
+   /** @function main */
+   int main( int argc, char** argv )
+   {
+     /// Load source image and convert it to gray
+     src = imread( argv[1], 1 );
+
+     /// Convert image to gray and blur it
+     cvtColor( src, src_gray, CV_BGR2GRAY );
+     blur( src_gray, src_gray, Size(3,3) );
+
+     /// Create Window
+     char* source_window = "Source";
+     namedWindow( source_window, CV_WINDOW_AUTOSIZE );
+     imshow( source_window, src );
+
+     createTrackbar( " Threshold:", "Source", &thresh, max_thresh, thresh_callback );
+     thresh_callback( 0, 0 );
+
+     waitKey(0);
+     return(0);
+   }
+
+   /** @function thresh_callback */
+   void thresh_callback(int, void* )
+   {
+     Mat threshold_output;
+     vector<vector<Point> > contours;
+     vector<Vec4i> hierarchy;
+
+     /// Detect edges using Threshold
+     threshold( src_gray, threshold_output, thresh, 255, THRESH_BINARY );
+     /// Find contours  
+     findContours( threshold_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
+
+     /// Find the rotated rectangles and ellipses for each contour
+     vector<RotatedRect> minRect( contours.size() );
+     vector<RotatedRect> minEllipse( contours.size() );
+
+     for( int i = 0; i < contours.size(); i++ )
+        { minRect[i] = minAreaRect( Mat(contours[i]) ); 
+          if( contours[i].size() > 5 )
+            { minEllipse[i] = fitEllipse( Mat(contours[i]) ); }
+        } 
+
+     /// Draw contours + rotated rects + ellipses
+     Mat drawing = Mat::zeros( threshold_output.size(), CV_8UC3 );
+     for( int i = 0; i< contours.size(); i++ )
+        { 
+          Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
+          // contour
+          drawContours( drawing, contours, i, color, 1, 8, vector<Vec4i>(), 0, Point() ); 
+          // ellipse
+          ellipse( drawing, minEllipse[i], color, 2, 8 );
+          // rotated rectangle        
+          Point2f rect_points[4]; minRect[i].points( rect_points );
+          for( int j = 0; j < 4; j++ )
+             line( drawing, rect_points[j], rect_points[(j+1)%4], color, 1, 8 ); 
+        }
+
+     /// Show in a window
+     namedWindow( "Contours", CV_WINDOW_AUTOSIZE );
+     imshow( "Contours", drawing ); 
+   }
+
+Explanation
+============
+
+Result
+======
+
+#. Here it is:
+
+   ========== ==========  
+    |BRE_0|   |BRE_1|   
+   ========== ==========   
+
+   .. |BRE_0|  image:: images/Bounding_Rotated_Ellipses_Source_Image.jpg
+                    :height: 300pt
+                    :align: middle
+
+   .. |BRE_1|  image:: images/Bounding_Rotated_Ellipses_Result.jpg
+                    :height: 300pt
+                    :align: middle   
+