ENH: Add test for the itk::BoundedReciprocalImageFilter class

Add a test for the `itk::BoundedReciprocalImageFilter` class.

Modules/Filtering/ImageIntensity/test/CMakeLists.txt

@@ -1,5 +1,6 @@
 itk_module_test()
 set(ITKImageIntensityTests
+itkBoundedReciprocalImageFilterTest.cxx
 itkCosImageFilterAndAdaptorTest.cxx
 itkExpImageFilterAndAdaptorTest.cxx
 itkVectorRescaleIntensityImageFilterTest.cxx
@@ -100,6 +101,8 @@ CreateTestDriver(ITKImageIntensity  "${ITKImageIntensity-Test_LIBRARIES}" "${ITK
 
 set(TEMP ${ITK_TEST_OUTPUT_DIR})
 
+itk_add_test(NAME itkBoundedReciprocalImageFilterTest
+      COMMAND ITKImageIntensityTestDriver itkBoundedReciprocalImageFilterTest DATA{${ITK_DATA_ROOT}/Input/Gourds.png})
 itk_add_test(NAME itkCosImageFilterAndAdaptorTest
       COMMAND ITKImageIntensityTestDriver itkCosImageFilterAndAdaptorTest)
 itk_add_test(NAME itkVectorRescaleIntensityImageFilterTest

Modules/Filtering/ImageIntensity/test/itkBoundedReciprocalImageFilterTest.cxx

@@ -0,0 +1,84 @@
+/*=========================================================================
+ *
+ *  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.
+ *
+ *=========================================================================*/
+
+#include "itkBoundedReciprocalImageFilter.h"
+#include "itkImageFileReader.h"
+#include "itkImageRegionConstIterator.h"
+#include "itkTestingMacros.h"
+
+
+int
+itkBoundedReciprocalImageFilterTest(int argc, char * argv[])
+{
+  if (argc != 2)
+  {
+    std::cerr << "Missing parameters." << std::endl;
+    std::cerr << "Usage: " << itkNameOfTestExecutableMacro(argv) << " inputImage" << std::endl;
+    return EXIT_FAILURE;
+  }
+
+
+  auto testStatus = EXIT_SUCCESS;
+
+  constexpr int Dimension = 2;
+
+  using PixelType = float;
+  using ImageType = itk::Image<PixelType, Dimension>;
+
+  using ReciprocalFilterType = itk::BoundedReciprocalImageFilter<ImageType, ImageType>;
+
+  auto reciprocalFilter = ReciprocalFilterType::New();
+
+  ITK_EXERCISE_BASIC_OBJECT_METHODS(reciprocalFilter, BoundedReciprocalImageFilter, UnaryGeneratorImageFilter);
+
+
+  const auto inputImage = itk::ReadImage<ImageType>(argv[1]);
+
+  reciprocalFilter->SetInput(inputImage);
+
+  ITK_TRY_EXPECT_NO_EXCEPTION(reciprocalFilter->Update());
+
+
+  // Check the output image values
+  auto outputImage = reciprocalFilter->GetOutput();
+
+  using ImageIterator = itk::ImageRegionConstIterator<ImageType>;
+
+  ImageIterator inIter(inputImage, inputImage->GetBufferedRegion());
+  ImageIterator outIter(outputImage, outputImage->GetBufferedRegion());
+
+  double tolerance = 10e-6;
+  std::cerr.precision(static_cast<int>(itk::Math::abs(std::log10(tolerance))));
+
+  for (; !inIter.IsAtEnd() || !outIter.IsAtEnd(); ++inIter, ++outIter)
+  {
+    auto obtainedValue = outIter.Get();
+    auto expectedValue = static_cast<PixelType>(1.0 / (1.0 + static_cast<double>(inIter.Get())));
+    if (!itk::Math::FloatAlmostEqual(expectedValue, obtainedValue, 10, tolerance))
+    {
+      std::cerr << "Error at index " << inIter.GetIndex() << std::endl;
+      std::cerr << " output " << obtainedValue << std::endl;
+      std::cerr << " differs from " << expectedValue;
+      std::cerr << " by more than " << tolerance << std::endl;
+      testStatus = EXIT_FAILURE;
+    }
+  }
+
+  std::cout << "Test finished." << std::endl;
+  return testStatus;
+}

Testing/Data/Input/Gourds.png.sha512

@@ -0,0 +1 @@
+859fd5a9de82ac8bbdf81c1c75548ce340c36c46396c8f63bbe709fe572af54df3bf69e18ece04e84977db3fee7aafc50ea6d51926cec1891661fb45a1762907