Added Hough Lines Tutorial in reST

doc/conf.py

@@ -313,7 +313,10 @@ extlinks = {'cvt_color': ('http://opencv.willowgarage.com/documentation/cpp/imgp
             'laplacian': ('http://opencv.willowgarage.com/documentation/cpp/image_filtering.html#cv-laplacian%s', None),
 	    'canny': ('http://opencv.willowgarage.com/documentation/cpp/imgproc_feature_detection.html?#Canny%s', None),
 	    'copy_to': ('http://opencv.willowgarage.com/documentation/cpp/core_basic_structures.html?#Mat::copyTo%s', None), 	
-            'opencv_group' : ('http://tech.groups.yahoo.com/group/OpenCV/%s', None)
+            'opencv_group' : ('http://tech.groups.yahoo.com/group/OpenCV/%s', None),
+	    'hough_lines' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_feature_detection.html?#cv-houghlines%s', None),
+	    'hough_lines_p' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_feature_detection.html?#cv-houghlinesp%s', None),
+	    'hough_circles' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_feature_detection.html?#cv-houghcircles%s', None)
            }
 
 

doc/tutorials/imgproc/imgtrans/hough_circle/hough_circle.rst

+.. _hough_circle:
+
+Hough Circle Transform
+***********************
+
+Goal
+=====
+In this tutorial you will learn how to:
+
+* Use the OpenCV functions :hough_circles:`HoughCircles <>` to detect circles in an image.
+
+Code
+======
+
+#. **What does this program do?**
+ 
+   * Loads an image and blur it to reduce the noise
+   * Applies the *Hough Circle Transform* to the blurred image . 
+   * Display the detected circle in a window.
+
+#. The sample code that we will explain can be downloaded from `here <https://code.ros.org/svn/opencv/trunk/opencv/samples/cpp/houghlines.cpp>`_. A slightly fancier version (which shows both Hough standard and probabilistic with trackbars for changing the threshold values) can be found  `here <https://code.ros.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/HoughCircle_Demo.cpp>`_
+
+.. code-block:: cpp 
+
+   #include "opencv2/highgui/highgui.hpp"
+   #include "opencv2/imgproc/imgproc.hpp"
+   #include <iostream>
+   #include <stdio.h>
+
+   using namespace cv;
+
+   /** @function main */
+   int main(int argc, char** argv)
+   {
+     Mat src, src_gray;
+
+     /// Read the image
+     src = imread( argv[1], 1 );
+
+     if( !src.data )
+       { return -1; }
+
+     /// Convert it to gray 
+     cvtColor( src, src_gray, CV_BGR2GRAY );
+
+     /// Reduce the noise so we avoid false circle detection
+     GaussianBlur( src_gray, src_gray, Size(9, 9), 2, 2 );
+
+     vector<Vec3f> circles;
+
+     /// Apply the Hough Transform to find the circles
+     HoughCircles( src_gray, circles, CV_HOUGH_GRADIENT, 1, src_gray.rows/8, 200, 100, 0, 0 );
+
+     /// Draw the circles detected
+     for( size_t i = 0; i < circles.size(); i++ )
+     {
+         Point center(cvRound(circles[i][0]), cvRound(circles[i][1]));
+         int radius = cvRound(circles[i][2]);
+         // circle center
+         circle( src, center, 3, Scalar(0,255,0), -1, 8, 0 );
+         // circle outline
+         circle( src, center, radius, Scalar(0,0,255), 3, 8, 0 );
+      }
+
+     /// Show your results 
+     namedWindow( "Hough Circle Transform Demo", CV_WINDOW_AUTOSIZE );
+     imshow( "Hough Circle Transform Demo", src );
+
+     waitKey(0);
+     return 0;
+   }
+
+Result
+=======
+ 
+.. image:: images/Hough_Circle_Tutorial_Result.jpg
+   :alt: Result of detecting circles with Hough Transform
+   :align: center 

doc/tutorials/imgproc/pyramids/pyramids.rst

@@ -10,8 +10,8 @@ In this tutorial you will learn how to:
 
 * Use the OpenCV functions :pyr_up:`pyrUp <>` and :pyr_down:`pyrDown <>` to downsample  or upsample a given image.
   
-Cool Theory
-============
+Theory
+=======
 
 .. note::
    The explanation below belongs to the book **Learning OpenCV** by Bradski and Kaehler.

doc/tutorials/imgproc/table_of_content_imgproc/table_of_content_imgproc.rst

@@ -196,3 +196,39 @@ In this section you will learn about the image processing (manipulation) functio
                            :height: 100pt
                            :width:  100pt
 
+
+* :ref:`hough_lines`
+
+  ===================== ==============================================
+   |HoughLines|         *Title:* **Hough Line Transform**
+
+                        *Compatibility:* > OpenCV 2.0
+                        
+                        *Author:* |Author_AnaH|
+
+                        Where we learn how to detect lines
+
+  ===================== ==============================================
+  
+  .. |HoughLines| image:: images/imgtrans/Hough_Lines_Tutorial_Cover.jpg
+                        :height: 100pt
+                        :width:  100pt
+
+
+* :ref:`hough_circle`
+
+  ===================== ==============================================
+   |HoughCircle|        *Title:* **Hough Circle Transform**
+
+                        *Compatibility:* > OpenCV 2.0
+                        
+                        *Author:* |Author_AnaH|
+
+                        Where we learn how to detect circles
+
+  ===================== ==============================================
+  
+  .. |HoughCircle| image:: images/imgtrans/Hough_Circle_Tutorial_Cover.jpg
+                         :height: 100pt
+                         :width:  100pt
+