ENH: Add example derivativeImage

src/Filtering/ImageFeature/CMakeLists.txt

@@ -33,3 +33,6 @@ add_example(FindZeroCrossingsInSignedImage)
 #===================================
 
 add_example(AdditiveGaussianNoiseImageFilter)
+
+add_example(DerivativeImage)
+compare_to_baseline(EXAMPLE_NAME DerivativeImage BASELINE_PREFIX Output)

src/Filtering/ImageFeature/DerivativeImage/BrainProtonDensitySlice.png.sha512

@@ -0,0 +1 @@
+86cbe2a809e90d72fb464868449477fe6d83809ddd0493cfca92033d7d3dd4bc3e0b831b17735926ed990735234a4eb8034aeaca70a3f5ba18fffe8f3c8e7eaa

src/Filtering/ImageFeature/DerivativeImage/CMakeLists.txt

@@ -0,0 +1,34 @@
+cmake_minimum_required(VERSION 3.16.3)
+
+project( DerivativeImage )
+
+find_package( ITK REQUIRED )
+include( ${ITK_USE_FILE} )
+
+add_executable( DerivativeImage Code.cxx )
+target_link_libraries( DerivativeImage ${ITK_LIBRARIES} )
+
+install( TARGETS DerivativeImage
+  DESTINATION bin/ITKSphinxExamples/Filtering/ImageFeature
+  COMPONENT Runtime
+  )
+
+install( FILES Code.cxx CMakeLists.txt
+  DESTINATION share/ITKSphinxExamples/Code/Filtering/ImageFeature/DerivativeImage
+  COMPONENT Code
+  )
+
+enable_testing()
+add_test( NAME DerivativeImageTest
+  COMMAND ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/DerivativeImage
+    ${CMAKE_CURRENT_BINARY_DIR}/BrainProtonDensitySlice.png
+    Output.mha Output_normalized.mha 1 1
+  )
+
+#if( ITK_WRAP_PYTHON )
+#  add_test( NAME DerivativeImageTestPython
+#    COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/Code.py
+#      ${CMAKE_CURRENT_BINARY_DIR}/BrainProtonDensitySlice.png
+#      OutputPython.png
+#    )
+#endif()

src/Filtering/ImageFeature/DerivativeImage/Code.cxx

@@ -0,0 +1,190 @@
+/*=========================================================================
+ *
+ *  Copyright NumFOCUS
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *         https://www.apache.org/licenses/LICENSE-2.0.txt
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *=========================================================================*/
+
+//  Software Guide : BeginCommandLineArgs
+//    INPUTS:  {BrainProtonDensitySlice.png}
+//    ARGUMENTS: {DerivativeImageFilterFloatOutput.mhd}
+//    OUTPUTS: {DerivativeImageFilterOutput.png}
+//    ARGUMENTS:    1 0
+//  Software Guide : EndCommandLineArgs
+
+//  Software Guide : BeginLatex
+//
+//  The \doxygen{DerivativeImageFilter} is used for computing the partial
+//  derivative of an image, the derivative of an image along a particular
+//  axial direction.
+//
+//  \index{itk::DerivativeImageFilter}
+//
+//  Software Guide : EndLatex
+
+
+#include "itkImage.h"
+#include "itkImageFileReader.h"
+#include "itkImageFileWriter.h"
+#include "itkRescaleIntensityImageFilter.h"
+
+//  Software Guide : BeginLatex
+//
+//  The header file corresponding to this filter should be included first.
+//
+//  \index{itk::DerivativeImageFilter!header}
+//
+//  Software Guide : EndLatex
+
+
+// Software Guide : BeginCodeSnippet
+#include "itkDerivativeImageFilter.h"
+// Software Guide : EndCodeSnippet
+
+
+int
+main(int argc, char * argv[])
+{
+  if (argc < 6)
+  {
+    std::cerr << "Usage: " << std::endl;
+    std::cerr << argv[0] << "  inputImageFile   outputImageFile  normalizedOutputImageFile ";
+    std::cerr << " derivativeOrder direction" << std::endl;
+    return EXIT_FAILURE;
+  }
+
+
+  //  Software Guide : BeginLatex
+  //
+  //  Next, the pixel types for the input and output images must be defined
+  //  and, with them, the image types can be instantiated. Note that it is
+  //  important to select a signed type for the image, since the values of the
+  //  derivatives will be positive as well as negative.
+  //
+  //  Software Guide : EndLatex
+
+  // Software Guide : BeginCodeSnippet
+  using InputPixelType = float;
+  using OutputPixelType = float;
+
+  constexpr unsigned int Dimension = 2;
+
+  using InputImageType = itk::Image<InputPixelType, Dimension>;
+  using OutputImageType = itk::Image<OutputPixelType, Dimension>;
+  // Software Guide : EndCodeSnippet
+
+
+  using ReaderType = itk::ImageFileReader<InputImageType>;
+  using WriterType = itk::ImageFileWriter<OutputImageType>;
+
+  auto reader = ReaderType::New();
+  auto writer = WriterType::New();
+
+  reader->SetFileName(argv[1]);
+  writer->SetFileName(argv[2]);
+
+  //  Software Guide : BeginLatex
+  //
+  //  Using the image types, it is now possible to define the filter type
+  //  and create the filter object.
+  //
+  //  \index{itk::DerivativeImageFilter!instantiation}
+  //  \index{itk::DerivativeImageFilter!New()}
+  //  \index{itk::DerivativeImageFilter!Pointer}
+  //
+  //  Software Guide : EndLatex
+
+  // Software Guide : BeginCodeSnippet
+  using FilterType = itk::DerivativeImageFilter<InputImageType, OutputImageType>;
+
+  auto filter = FilterType::New();
+  // Software Guide : EndCodeSnippet
+
+
+  //  Software Guide : BeginLatex
+  //
+  //  The order of the derivative is selected with the \code{SetOrder()}
+  //  method.  The direction along which the derivative will be computed is
+  //  selected with the \code{SetDirection()} method.
+  //
+  //  \index{itk::DerivativeImageFilter!SetOrder()}
+  //  \index{itk::DerivativeImageFilter!SetDirection()}
+  //
+  //  Software Guide : EndLatex
+
+  // Software Guide : BeginCodeSnippet
+  filter->SetOrder(std::stoi(argv[4]));
+  filter->SetDirection(std::stoi(argv[5]));
+  // Software Guide : EndCodeSnippet
+
+
+  //  Software Guide : BeginLatex
+  //
+  //  The input to the filter can be taken from any other filter, for example
+  //  a reader. The output can be passed down the pipeline to other filters,
+  //  for example, a writer. An \code{Update()} call on any downstream filter
+  //  will trigger the execution of the derivative filter.
+  //
+  //  \index{itk::DerivativeImageFilter!SetInput()}
+  //  \index{itk::DerivativeImageFilter!GetOutput()}
+  //
+  //  Software Guide : EndLatex
+
+
+  // Software Guide : BeginCodeSnippet
+  filter->SetInput(reader->GetOutput());
+  writer->SetInput(filter->GetOutput());
+  writer->Update();
+  // Software Guide : EndCodeSnippet
+
+
+  //  Software Guide : BeginLatex
+  //
+  // \begin{figure}
+  // \center
+  // \includegraphics[width=0.44\textwidth]{BrainProtonDensitySlice}
+  // \includegraphics[width=0.44\textwidth]{DerivativeImageFilterOutput}
+  // \itkcaption[Effect of the Derivative filter.]{Effect of the Derivative
+  // filter on a slice from a MRI proton density brain image.}
+  // \label{fig:DerivativeImageFilterOutput}
+  // \end{figure}
+  //
+  //  Figure \ref{fig:DerivativeImageFilterOutput} illustrates the effect of
+  //  the DerivativeImageFilter on a slice of MRI brain image. The derivative
+  //  is taken along the $x$ direction.  The sensitivity to noise in the image
+  //  is evident from this result.
+  //
+  //  Software Guide : EndLatex
+
+
+  using WriteImageType = itk::Image<unsigned char, Dimension>;
+
+  using NormalizeFilterType = itk::RescaleIntensityImageFilter<OutputImageType, WriteImageType>;
+
+  using NormalizedWriterType = itk::ImageFileWriter<WriteImageType>;
+
+  auto normalizer = NormalizeFilterType::New();
+  auto normalizedWriter = NormalizedWriterType::New();
+
+  normalizer->SetInput(filter->GetOutput());
+  normalizedWriter->SetInput(normalizer->GetOutput());
+
+  normalizer->SetOutputMinimum(0);
+  normalizer->SetOutputMaximum(255);
+
+  normalizedWriter->SetFileName(argv[3]);
+  normalizedWriter->Update();
+
+  return EXIT_SUCCESS;
+}

src/Filtering/ImageFeature/DerivativeImage/Documentation.rst

@@ -0,0 +1,49 @@
+:name: DerivativeImage
+
+Compute Derivative
+===================
+
+.. index::
+   single: DerivativeImageFilter
+
+Synopsis
+--------
+
+This filter computes a n-th Derivative of a scalar-valued image in a specified direction.
+
+
+Results
+-------
+
+.. figure:: BrainProtonDensitySlice.png
+  :scale: 50%
+  :alt: Input image
+
+  Input image
+
+.. figure:: Output.png
+  :scale: 50%
+  :alt: Output image
+
+  Output image
+
+
+.. figure:: Output_normalized.png
+  :scale: 50%
+  :alt: Output normalized image
+
+  Output normalized image
+
+Code
+----
+
+C++
+...
+
+.. literalinclude:: Code.cxx
+   :lines: 18-
+
+Classes demonstrated
+--------------------
+
+.. breathelink:: itk::DerivativeImageFilter

src/Filtering/ImageFeature/DerivativeImage/Output.mha.sha512

@@ -0,0 +1 @@
+1bba1d72a84bf2d171c85834a9e9e7e485b26ef60a05fb0fe93c1103ff920071fc5ccc14b7c27348abf5dcd537825838bdefd7a8b27336c8115677ceb80af227

src/Filtering/ImageFeature/DerivativeImage/Output.png.sha512

@@ -0,0 +1 @@
+29e67a22a4218b780ca75af045544178e193aefce7ceff7923fcd858068918efab6d41c37ea3020fe3747abb35172a67be33ff85c9595ff3a19fffdc37d6a2d1

src/Filtering/ImageFeature/DerivativeImage/Output_normalized.mha.sha512

@@ -0,0 +1 @@
+346c92583d339826d3ebf9cede566d1d215e50b3cd431fe63e693e97f03f0b9f48c2f461a4dd73218f0e5852f5a12e9d90e8360c522fb8e5752aadc86e6d3362

src/Filtering/ImageFeature/DerivativeImage/Output_normalized.png.sha512

@@ -0,0 +1 @@
+1cf70adf30331a9c1a084e64f13dc7c263d212ebcad0880048413af3490ee81f5e1f77caf5cd98b52a0181a66ad2ced1c02392dd8c8e2d46f615e93d205df6c4

src/Filtering/ImageFeature/index.rst

@@ -10,6 +10,7 @@ ImageFeature
   BilateralFilterAnImage/Documentation.rst
   ComputeLaplacian/Documentation.rst
   DetectEdgesWithCannyEdgeDetectionFilter/Documentation.rst
+  DerivativeImage/Documentation.rst
   ExtractContoursFromImage/Documentation.rst
   FindZeroCrossingsInSignedImage/Documentation.rst
   LaplacianRecursiveGaussianImageFilter/Documentation.rst