DOC: review FrostImageFilter

Examples/BasicFilters/FrostImageFilter.cxx

@@ -23,34 +23,6 @@
 ./FrostImageFilter Input/GomaSmall.png Output/GomaSmallFrostFiltered.png 5 0.1
 */
 
-
-// This example illustrates the use of the \doxygen{otb}{FrostImageFilter}.
-// This filter belongs to the family of the edge-preserving smoothing
-// filters which are usually used for speckle reduction in radar
-// images.
-//
-// This filter uses a negative exponential convolution kernel.
-// The output of the filter for pixel p is:
-//      $ \hat I_{s}=\sum_{p\in\eta_{p}} m_{p}I_{p} $
-//
-// where :   $ m_{p}=\frac{KC_{s}^{2}\exp(-KC_{s}^{2}d_{s, p})}{\sum_{p\in\eta_{p}} KC_{s}^{2}\exp(-KC_{s}^{2}d_{s, p})} $
-//    and  $ d_{s, p}=\sqrt{(i-i_{p})^2+(j-j_{p})^2} $
-//
-// \begin{itemize}
-// \item $ K $     : the decrease coefficient
-// \item $ (i, j)$ : the coordinates of the pixel inside the region
-// defined by $ \eta_{s} $
-// \item $ (i_{p}, j_{p})$ : the coordinates of the pixels belonging to $ \eta_{p} \subset \eta_{s} $
-// \item $ C_{s}$ : the variation coefficient computed over $ \eta_{p}$
-// \end{itemize}
-//
-//
-//
-// Most of this example is similar to the previous one and only the differences
-// will be highlighted.
-//
-// First, we need to include the header:
-
 #include "otbFrostImageFilter.h"
 
 #include "otbImage.h"
@@ -68,16 +40,12 @@ int main(int argc, char* argv[])
   }
 
   typedef unsigned char PixelType;
-
   typedef otb::Image<PixelType, 2> InputImageType;
   typedef otb::Image<PixelType, 2> OutputImageType;
 
-  //  The filter can be instantiated using the image types defined previously.
-
+  // The filter can be instantiated using the image types defined previously.
   typedef otb::FrostImageFilter<InputImageType, OutputImageType> FilterType;
-
   typedef otb::ImageFileReader<InputImageType> ReaderType;
-
   typedef otb::ImageFileWriter<OutputImageType> WriterType;
 
   ReaderType::Pointer reader = ReaderType::New();
@@ -87,22 +55,12 @@ int main(int argc, char* argv[])
   writer->SetInput(filter->GetOutput());
   reader->SetFileName(argv[1]);
 
-  //  The image obtained with the reader is passed as input to the
-  //  \doxygen{otb}{FrostImageFilter}.
-  //
-  //  \index{otb::FrostImageFilter!SetInput()}
-  //  \index{otb::FileImageReader!GetOutput()}
-
+  // The image obtained with the reader is passed as input to the FrostImageFilter
   filter->SetInput(reader->GetOutput());
 
-  //  The method \code{SetRadius()} defines the size of the window to
-  //  be used for the computation of the local statistics. The method
-  //  \code{SetDeramp()} sets the $K$ coefficient.
-  //
-  //  \index{otb::FrostImageFilter!SetRadius()}
-  //  \index{otb::FrostImageFilter!SetDeramp()}
-  //  \index{SetDeramp()!otb::FrostImageFilter}
-
+  // The method SetRadius() defines the size of the window to
+  // be used for the computation of the local statistics. The method
+  // SetDeramp() sets the K coefficient.
   FilterType::SizeType Radius;
   Radius[0] = atoi(argv[3]);
   Radius[1] = atoi(argv[3]);
@@ -112,22 +70,4 @@ int main(int argc, char* argv[])
 
   writer->SetFileName(argv[2]);
   writer->Update();
-
-  // Figure~\ref{fig:FROST_FILTER} shows the result of applying the Frost
-  // filter to a SAR image.
-  // \begin{figure}
-  // \center
-  // \includegraphics[width=0.44\textwidth]{GomaSmall.eps}
-  // \includegraphics[width=0.44\textwidth]{GomaSmallFrostFiltered.eps}
-  // \itkcaption[Frost Filter Application]{Result of applying the
-  // \doxygen{otb}{FrostImageFilter} to a SAR image.}
-  // \label{fig:FROST_FILTER}
-  // \end{figure}
-  //
-  //  \relatedClasses
-  //  \begin{itemize}
-  //  \item \doxygen{otb}{LeeImageFilter}
-  //  \end{itemize}
-
-  return EXIT_SUCCESS;
 }

Examples/BasicFilters/FrostImageFilter.rst

+This example illustrates the use of the :doxygen:`FrostImageFilter`.
+This filter belongs to the family of the edge-preserving smoothing
+filters which are usually used for speckle reduction in radar
+images.
+
+This filter uses a negative exponential convolution kernel.
+The output of the filter for pixel p is:
+
+.. math::
+
+   \hat I_{s}=\sum_{p\in\eta_{p}} m_{p}I_{p}
+
+   m_{p}=\frac{KC_{s}^{2}\exp(-KC_{s}^{2}d_{s, p})}{\sum_{p\in\eta_{p}} KC_{s}^{2}\exp(-KC_{s}^{2}d_{s, p})}
+
+   d_{s, p}=\sqrt{(i-i_{p})^2+(j-j_{p})^2}
+
+where:
+
+* :math:`K`: the decrease coefficient
+* :math:`(i, j)`: the coordinates of the pixel inside the region defined by :math:`\eta_{s}`
+* :math:`(i_{p}, j_{p})`: the coordinates of the pixels belonging to :math:`\eta_{p} \subset \eta_{s}`
+* :math:`C_{s}`: the variation coefficient computed over :math:`\eta_{p}`
+
+.. |image1| image:: /Input/GomaSmall.png
+
+.. |image2| image:: /Output/GomaSmallFrostFiltered.png
+
+.. _Figure1:
+
++--------------------------+-------------------------+
+|        |image1|          |         |image2|        |
++--------------------------+-------------------------+
+
+    Result of applying the FrostImageFilter to a SAR image.