Added Equalized Histogram reST tutorial + corrected Smoothing tutorial (images…

Added Equalized Histogram reST tutorial + corrected Smoothing tutorial (images reduced and fixed link)

doc/conf.py

@@ -320,7 +320,8 @@ extlinks = {'cvt_color': ('http://opencv.willowgarage.com/documentation/cpp/imgp
 	    'remap' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_geometric_image_transformations.html?#remap%s', None),
 	    'warp_affine' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_geometric_image_transformations.html?#cv-warpaffine%s' , None),
 	    'get_rotation_matrix_2d' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_geometric_image_transformations.html?#cv-getrotationmatrix2d%s', None),
-            'get_affine_transform' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_geometric_image_transformations.html?#cv-getaffinetransform%s', None)
+            'get_affine_transform' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_geometric_image_transformations.html?#cv-getaffinetransform%s', None),
+            'equalize_hist' : ('http://opencv.willowgarage.com/documentation/cpp/imgproc_histograms.html?#equalizeHist%s', None)
            }
 
 

doc/tutorials/imgproc/histograms/back_projection/back_projection.rst

+.. _back_projection:
+
+Back Projection
+****************

doc/tutorials/imgproc/histograms/histogram_calculation/histogram_calculation.rst

+.. _histogram_calculation:
+
+Histogram Calculation
+**********************

doc/tutorials/imgproc/histograms/histogram_comparison/histogram_comparison.rst

+.. _histogram_comparison:
+
+Histogram Comparison
+********************

doc/tutorials/imgproc/histograms/histogram_equalization/histogram_equalization.rst

+.. _histogram_equalization:
+
+Histogram Equalization
+**********************
+
+Goal
+====
+
+In this tutorial you will learn:
+
+.. container:: enumeratevisibleitemswithsquare
+
+   * What an image histogram is and why it is useful
+
+   * To equalize histograms of images by using the OpenCV function:equalize_hist:`equalizeHist <>` 
+
+
+
+Theory
+======
+
+What is an Image Histogram?
+---------------------------
+
+.. container:: enumeratevisibleitemswithsquare
+
+   * It is a graphical representation of the intensity distribution of an image. 
+
+   * It quantifies the number of pixels for each intensity value considered.
+
+.. image:: images/Histogram_Equalization_Theory_0.jpg
+        :height: 200pt
+        :align: center 
+
+
+What is Histogram Equalization?
+-------------------------------
+
+.. container:: enumeratevisibleitemswithsquare
+
+   * It is a method that improves the contrast in an image, in order to stretch out the intensity range.
+
+   * To make it clearer, from the image above, you can see that the pixels seem clustered around the middle of the available range of intensities. What Histogram Equalization does is to *stretch out* this range. Take a look at the figure below: The green circles indicate the *underpopulated* intensities. After applying the equalization, we get an histogram like the figure in the center. The resulting image is shown in the picture at right.
+
+.. image:: images/Histogram_Equalization_Theory_1.jpg
+          :height: 200pt
+          :align: center 
+
+How does it work?
+-----------------
+
+.. container:: enumeratevisibleitemswithsquare
+
+   * Equalization implies *mapping* one distribution (the given histogram) to another distribution (a wider and more uniform distribution of intensity values) so the intensity values are spreaded over the whole range. 
+
+   * To accomplish the equalization effect, the remapping should be the *cumulative distribution function (cdf)* (more details, refer to *Learning OpenCV*). For the histogram :math:`H(i)`, its *cumulative distribution* :math:`H^{'}(i)` is:
+
+     .. math::
+
+        H^{'}(i) = \sum_{0 \le j < i} H(j) 
+
+     To use this as a remapping function, we have to normalize :math:`H^{'}(i)` such that the maximum value is 255 ( or the maximum value for the intensity of the image ). From the example above, the cumulative function is:
+
+     .. image:: images/Histogram_Equalization_Theory_2.jpg
+              :height: 200pt
+              :align: center 
+
+   * Finally, we use a simple remapping procedure to obtain the intensity values of the equalized image:
+
+     .. math::
+ 
+        equalized( x, y ) = H^{'}( src(x,y) )
+
+Code
+====
+
+.. container:: enumeratevisibleitemswithsquare
+
+   * **What does this program do?**
+ 
+     .. container:: enumeratevisibleitemswithsquare
+
+        * Loads an image
+        * Convert the original image to grayscale 
+        * Equalize the Histogram by using the OpenCV function :equalize_hist:`EqualizeHist <>`
+        * Display the source and equalized images in a window.
+
+   * **Downloadable code**:
+     Click `here <https://code.ros.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/Histograms_Matching/EqualizeHist_Demo.cpp>`_
+
+   * **Code at glance:**
+
+.. code-block:: cpp
+
+   #include "opencv2/highgui/highgui.hpp"
+   #include "opencv2/imgproc/imgproc.hpp"
+   #include <iostream>
+   #include <stdio.h>
+
+   using namespace cv;
+   using namespace std;
+
+   /**  @function main */
+   int main( int argc, char** argv )
+   {
+     Mat src, dst;
+
+     char* source_window = "Source image";
+     char* equalized_window = "Equalized Image";
+
+     /// Load image
+     src = imread( argv[1], 1 );
+
+     if( !src.data )
+       { cout<<"Usage: ./Histogram_Demo <path_to_image>"<<endl;
+         return -1;}
+
+     /// Convert to grayscale
+     cvtColor( src, src, CV_BGR2GRAY );
+
+     /// Apply Histogram Equalization
+     equalizeHist( src, dst );
+ 
+     /// Display results
+     namedWindow( source_window, CV_WINDOW_AUTOSIZE );
+     namedWindow( equalized_window, CV_WINDOW_AUTOSIZE );
+
+     imshow( source_window, src );
+     imshow( equalized_window, dst );
+ 
+     /// Wait until user exits the program 
+     waitKey(0);
+
+     return 0;
+   }
+
+Explanation
+===========
+
+#. Declare the source and destination images as well as the windows names:  
+
+   .. code-block:: cpp
+
+      Mat src, dst;
+
+      char* source_window = "Source image";
+      char* equalized_window = "Equalized Image";
+
+#. Load the source image:
+ 
+   .. code-block:: cpp
+
+      src = imread( argv[1], 1 );
+
+      if( !src.data )
+        { cout<<"Usage: ./Histogram_Demo <path_to_image>"<<endl;
+          return -1;}
+
+#. Convert it to grayscale:
+
+   ..  code-block:: cpp
+
+       cvtColor( src, src, CV_BGR2GRAY );
+
+#. Apply histogram equalization with the function :equalize_hist:`equalizeHist <>` :
+
+   .. code-block:: cpp
+
+      equalizeHist( src, dst );
+ 
+   As it can  be easily seen, the only arguments are the original image and the output (equalized) image.
+
+#. Display both images (original and equalized) :
+
+   .. code-block::  cpp
+
+      namedWindow( source_window, CV_WINDOW_AUTOSIZE );
+      namedWindow( equalized_window, CV_WINDOW_AUTOSIZE );
+
+      imshow( source_window, src );
+      imshow( equalized_window, dst );
+ 
+#. Wait until user exists the program
+     
+   .. code-block:: cpp
+
+      waitKey(0);
+      return 0;
+
+
+Results
+=======
+
+#. To appreciate better the results of equalization, let's introduce an image with not much contrast, such as:
+
+   .. image:: images/Histogram_Equalization_Original_Image.jpg
+            :height: 200pt
+            :align: center 
+
+   which, by the way, has this histogram:
+
+   .. image:: images/Histogram_Equalization_Original_Histogram.jpg
+            :height: 150pt
+            :align: center 
+
+   notice that the pixels are clustered around the center of the histogram.
+
+#. After applying the equalization with our program, we get this result:
+
+   .. image:: images/Histogram_Equalization_Equalized_Image.jpg
+            :height: 200pt
+            :align: center 
+
+   this image has certainly more contrast. Check out its new histogram like this:
+
+   .. image:: images/Histogram_Equalization_Equalized_Histogram.jpg
+            :height: 150pt
+            :align: center
+
+   Notice how the number of pixels is more distributed through the intensity range.
+
+
+.. note::
+   Are you wondering how did we draw the Histogram figures shown above? Check out the following tutorial!

doc/tutorials/imgproc/histograms/template_matching/template_matching.rst

+.. _template_matching:
+
+Template Matching
+*****************

doc/tutorials/imgproc/table_of_content_imgproc/table_of_content_imgproc.rst

@@ -24,7 +24,7 @@ In this section you will learn about the image processing (manipulation) functio
   
   ===================== ==============================================
   
-  .. |ImageProcessing_1| image:: images/Smoothing_Tutorial_Cover.png
+  .. |ImageProcessing_1| image:: images/Smoothing_Tutorial_Cover.jpg
                          :height: 90pt
                          :width:  90pt
   
@@ -283,21 +283,111 @@ In this section you will learn about the image processing (manipulation) functio
   .. |WarpAffine| image:: images/imgtrans/Warp_Affine_Tutorial_Cover.jpg
                         :height: 90pt
                         :width:  90pt
+
++ 
+
+  .. tabularcolumns:: m{100pt} m{300pt}
+  .. cssclass:: toctableopencv
+  
+  ===================== ==============================================
+   |HistEqualization|   **Title:** :ref:`histogram_equalization`
+
+                        *Compatibility:* > OpenCV 2.0
+                        
+                        *Author:* |Author_AnaH|
+
+                        Where we learn how to improve the contrast in our images
+
+  ===================== ==============================================
+  
+  .. |HistEqualization| image:: images/histograms/Histogram_Equalization_Tutorial_Cover.jpg
+                              :height: 90pt
+                              :width:  90pt
+
++ 
+
+  .. tabularcolumns:: m{100pt} m{300pt}
+  .. cssclass:: toctableopencv
+  
+  ===================== ==============================================
+   |HistCalculation|    **Title:** :ref:`histogram_calculation`
+
+                        *Compatibility:* > OpenCV 2.0
+                        
+                        *Author:* |Author_AnaH|
+
+                        Where we learn how to create and generate histograms
+
+  ===================== ==============================================
+  
+  .. |HistCalculation| image:: images/histograms/Histogram_Calculation_Tutorial_Cover.jpg
+                             :height: 90pt
+                             :width:  90pt
+
++ 
+
+  .. tabularcolumns:: m{100pt} m{300pt}
+  .. cssclass:: toctableopencv
+  
+  ===================== ==============================================
+   |HistComparison|     **Title:** :ref:`histogram_comparison`
+
+                        *Compatibility:* > OpenCV 2.0
+                        
+                        *Author:* |Author_AnaH|
+
+                        Where we learn to calculate metrics between histograms
+
+  ===================== ==============================================
+  
+  .. |HistComparison| image:: images/histograms/Histogram_Comparison_Tutorial_Cover.jpg
+                            :height: 90pt
+                            :width:  90pt
+
++ 
+
+  .. tabularcolumns:: m{100pt} m{300pt}
+  .. cssclass:: toctableopencv
+  
+  ===================== ==============================================
+   |BackProjection|     **Title:** :ref:`back_projection`
+
+                        *Compatibility:* > OpenCV 2.0
+                        
+                        *Author:* |Author_AnaH|
+
+                        Where we learn how to use histograms to find similar objects in images
+
+  ===================== ==============================================
+  
+  .. |BackProjection| image:: images/histograms/Back_Projection_Tutorial_Cover.jpg
+                            :height: 90pt
+                            :width:  90pt
+
++ 
+
+  .. tabularcolumns:: m{100pt} m{300pt}
+  .. cssclass:: toctableopencv
+  
+  ===================== ==============================================
+   |TemplateMatching|   **Title:** :ref:`template_matching`
+
+                        *Compatibility:* > OpenCV 2.0
+                        
+                        *Author:* |Author_AnaH|
+
+                        Where we learn how to match templates in an image
+
+  ===================== ==============================================
+  
+  .. |TemplateMatching| image:: images/histograms/Template_Matching_Tutorial_Cover.jpg
+                              :height: 90pt
+                              :width:  90pt
+
   
 .. toctree::
    :hidden:
 
-   ../gausian_median_blur_bilateral_filter/gausian_median_blur_bilateral_filter
-   ../erosion_dilatation/erosion_dilatation
-   ../opening_closing_hats/opening_closing_hats
-   ../pyramids/pyramids
-   ../threshold/threshold
-   ../imgtrans/filter_2d/filter_2d
-   ../imgtrans/copyMakeBorder/copyMakeBorder
-   ../imgtrans/sobel_derivatives/sobel_derivatives
-   ../imgtrans/laplace_operator/laplace_operator
-   ../imgtrans/canny_detector/canny_detector
-   ../imgtrans/hough_lines/hough_lines
-   ../imgtrans/hough_circle/hough_circle
-   ../imgtrans/remap/remap
-   ../imgtrans/warp_affine/warp_affine
+
+
+