1 /*=========================================================================
2 *
3 * Copyright Insight Software Consortium
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0.txt
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 *=========================================================================*/
18
19 #include "itkMath.h"
20 #include "itkTanImageFilter.h"
21 #include "itkTanImageAdaptor.h"
22 #include "itkSubtractImageFilter.h"
23 #include "itkTestingMacros.h"
24
itkTanImageFilterAndAdaptorTest(int,char * [])25 int itkTanImageFilterAndAdaptorTest( int, char* [] )
26 {
27
28 // Define the dimension of the images
29 constexpr unsigned int ImageDimension = 3;
30
31 // Declare the pixel types of the images
32 using PixelType = float;
33
34 // Declare the types of the images
35 using InputImageType = itk::Image< PixelType, ImageDimension >;
36 using OutputImageType = itk::Image< PixelType, ImageDimension >;
37
38 // Declare appropriate Iterator types for each image
39 using InputIteratorType = itk::ImageRegionIteratorWithIndex<InputImageType>;
40 using OutputIteratorType = itk::ImageRegionIteratorWithIndex<OutputImageType>;
41
42 // Declare the type of the index to access images
43 using IndexType = itk::Index< ImageDimension >;
44
45 // Declare the type of the size
46 using SizeType = itk::Size< ImageDimension >;
47
48 // Declare the type of the Region
49 using RegionType = itk::ImageRegion< ImageDimension >;
50
51 // Create the input image
52 InputImageType::Pointer inputImage = InputImageType::New();
53
54 // Define its size, and start index
55 SizeType size;
56 size[0] = 2;
57 size[1] = 2;
58 size[2] = 2;
59
60 IndexType start;
61 start[0] = 0;
62 start[1] = 0;
63 start[2] = 0;
64
65 RegionType region;
66 region.SetIndex( start );
67 region.SetSize( size );
68
69 // Initialize the input image
70 inputImage->SetLargestPossibleRegion( region );
71 inputImage->SetBufferedRegion( region );
72 inputImage->SetRequestedRegion( region );
73 inputImage->Allocate();
74
75 // Create one iterator for the input image (this is a light object)
76 InputIteratorType it( inputImage, inputImage->GetBufferedRegion() );
77
78 // Initialize the content of the input image
79 const double value = itk::Math::pi / 6.0;
80 it.GoToBegin();
81 while( !it.IsAtEnd() )
82 {
83 it.Set( value );
84 ++it;
85 }
86
87 // Declare the type for the Tan filter
88 using FilterType = itk::TanImageFilter< InputImageType,
89 OutputImageType >;
90
91 // Create the filter
92 FilterType::Pointer filter = FilterType::New();
93
94 EXERCISE_BASIC_OBJECT_METHODS( filter, TanImageFilter,
95 UnaryGeneratorImageFilter );
96
97 // Set the input image
98 filter->SetInput( inputImage );
99
100
101 // Execute the filter
102 filter->Update();
103
104 // Get the filter output
105 OutputImageType::Pointer outputImage = filter->GetOutput();
106
107 // Create an iterator for going through the image output
108 OutputIteratorType ot( outputImage, outputImage->GetRequestedRegion() );
109
110 // Check the content of the result image
111 const OutputImageType::PixelType epsilon = 1e-6;
112 ot.GoToBegin();
113 it.GoToBegin();
114 while( !ot.IsAtEnd() )
115 {
116 const InputImageType::PixelType input = it.Get();
117 const OutputImageType::PixelType output = ot.Get();
118 const OutputImageType::PixelType tangent = std::tan(input);
119 if( !itk::Math::FloatAlmostEqual( tangent, output, 10, epsilon ) )
120 {
121 std::cerr.precision( static_cast< int >( itk::Math::abs( std::log10( epsilon ) ) ) );
122 std::cerr << "Error " << std::endl;
123 std::cerr << " std::tan( " << input << ") = " << tangent << std::endl;
124 std::cerr << " differs from " << output;
125 std::cerr << " by more than " << epsilon << std::endl;
126 return EXIT_FAILURE;
127 }
128 ++ot;
129 ++it;
130 }
131
132 //
133 // Test the itk::TanImageAdaptor
134
135 using AdaptorType = itk::TanImageAdaptor< InputImageType,
136 OutputImageType::PixelType >;
137
138 AdaptorType::Pointer tanAdaptor = AdaptorType::New();
139
140 EXERCISE_BASIC_OBJECT_METHODS( tanAdaptor, TanImageAdaptor,
141 ImageAdaptor );
142
143 tanAdaptor->SetImage( inputImage );
144
145 using DiffFilterType = itk::SubtractImageFilter<
146 OutputImageType,
147 AdaptorType,
148 OutputImageType >;
149
150 DiffFilterType::Pointer diffFilter = DiffFilterType::New();
151
152 diffFilter->SetInput1( outputImage );
153 diffFilter->SetInput2( tanAdaptor );
154
155 diffFilter->Update();
156
157 // Get the filter output
158 OutputImageType::Pointer diffImage = diffFilter->GetOutput();
159
160 // Check the content of the diff image
161 //
162
163 // Create an iterator for going through the image output
164 OutputIteratorType dt( diffImage, diffImage->GetRequestedRegion() );
165
166 dt.GoToBegin();
167 while( !dt.IsAtEnd() )
168 {
169 const OutputImageType::PixelType diff = dt.Get();
170 if( std::fabs( diff ) > epsilon )
171 {
172 std::cerr << "Error comparing results with Adaptors" << std::endl;
173 std::cerr << " difference = " << diff << std::endl;
174 std::cerr << " differs from 0 ";
175 std::cerr << " by more than " << epsilon << std::endl;
176 return EXIT_FAILURE;
177 }
178 ++dt;
179 }
180
181 return EXIT_SUCCESS;
182 }
183