ENH: Convert itkGaborKernelFunctionTest to GTest

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: hjmjohnson

Modules/Filtering/ImageSources/itk-module.cmake

@@ -5,6 +5,7 @@ itk_module(
   COMPILE_DEPENDS
     ITKCommon
   TEST_DEPENDS
+    ITKGoogleTest
     ITKTestKernel
     ITKImageIntensity
   DESCRIPTION "${DOCUMENTATION}"

Modules/Filtering/ImageSources/test/CMakeLists.txt

@@ -1,7 +1,6 @@
 itk_module_test()
 set(
   ITKImageSourcesTests
-  itkGaborKernelFunctionTest.cxx
   itkGaborImageSourceTest.cxx
   itkGaussianImageSourceTest.cxx
   itkGridImageSourceTest.cxx
@@ -11,12 +10,10 @@ set(
 
 createtestdriver(ITKImageSources "${ITKImageSources-Test_LIBRARIES}" "${ITKImageSourcesTests}")
 
-itk_add_test(
-  NAME itkGaborKernelFunctionTest
-  COMMAND
-    ITKImageSourcesTestDriver
-    itkGaborKernelFunctionTest
-)
+set(ITKImageSourcesGTests itkGaborKernelFunctionGTest.cxx)
+
+creategoogletestdriver(ITKImageSources "${ITKImageSources-Test_LIBRARIES}" "${ITKImageSourcesGTests}")
+
 itk_add_test(
   NAME itkGaborImageSourceTest0
   COMMAND

Modules/Filtering/ImageSources/test/itkGaborKernelFunctionGTest.cxx

@@ -0,0 +1,90 @@
+/*=========================================================================
+ *
+ *  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 "itkGaborKernelFunction.h"
+#include "itkMath.h"
+#include "itkGTest.h"
+
+TEST(GaborKernelFunction, BasicObjectMethods)
+{
+  using KernelFunctionType = itk::GaborKernelFunction<double>;
+  auto gabor = KernelFunctionType::New();
+
+  ITK_GTEST_EXERCISE_BASIC_OBJECT_METHODS(gabor, GaborKernelFunction, KernelFunctionBase);
+}
+
+TEST(GaborKernelFunction, SetGetParameters)
+{
+  using KernelFunctionType = itk::GaborKernelFunction<double>;
+  auto gabor = KernelFunctionType::New();
+
+  constexpr double sigma{ 1.5 };
+  gabor->SetSigma(sigma);
+  EXPECT_DOUBLE_EQ(gabor->GetSigma(), sigma);
+
+  constexpr double frequency{ 2.0 };
+  gabor->SetFrequency(frequency);
+  EXPECT_DOUBLE_EQ(gabor->GetFrequency(), frequency);
+
+  constexpr double phaseOffset{ 0.8 };
+  gabor->SetPhaseOffset(phaseOffset);
+  EXPECT_DOUBLE_EQ(gabor->GetPhaseOffset(), phaseOffset);
+
+  gabor->SetCalculateImaginaryPart(true);
+  EXPECT_TRUE(gabor->GetCalculateImaginaryPart());
+
+  gabor->CalculateImaginaryPartOn();
+  EXPECT_TRUE(gabor->GetCalculateImaginaryPart());
+
+  gabor->CalculateImaginaryPartOff();
+  EXPECT_FALSE(gabor->GetCalculateImaginaryPart());
+}
+
+TEST(GaborKernelFunction, EvaluateImaginaryPart)
+{
+  using KernelFunctionType = itk::GaborKernelFunction<double>;
+  auto gabor = KernelFunctionType::New();
+
+  gabor->SetSigma(1.5);
+  gabor->SetFrequency(2.0);
+  gabor->SetPhaseOffset(0.8);
+  gabor->CalculateImaginaryPartOn();
+
+  constexpr double tolerance{ 1e-12 };
+  constexpr double point{ 2.86 };
+  constexpr double expectedValue{ -0.13297125073713259 };
+
+  EXPECT_NEAR(gabor->Evaluate(point), expectedValue, tolerance);
+}
+
+TEST(GaborKernelFunction, EvaluateRealPart)
+{
+  using KernelFunctionType = itk::GaborKernelFunction<double>;
+  auto gabor = KernelFunctionType::New();
+
+  gabor->SetSigma(1.5);
+  gabor->SetFrequency(2.0);
+  gabor->SetPhaseOffset(0.8);
+  gabor->CalculateImaginaryPartOff();
+
+  constexpr double tolerance{ 1e-12 };
+  constexpr double point{ 2.86 };
+  constexpr double expectedValue{ 0.093234196962237226 };
+
+  EXPECT_NEAR(gabor->Evaluate(point), expectedValue, tolerance);
+}