1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
/*=========================================================================
*
* 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.
*
*=========================================================================*/
#ifndef itkVnlInverse1DFFTImageFilter_hxx
#define itkVnlInverse1DFFTImageFilter_hxx
#include "itkInverse1DFFTImageFilter.hxx"
#include "itkImageLinearConstIteratorWithIndex.h"
#include "itkImageLinearIteratorWithIndex.h"
#include "itkIndent.h"
#include "itkMetaDataObject.h"
#include "itkMacro.h"
#include "vnl/algo/vnl_fft_base.h"
#include "vnl/algo/vnl_fft_1d.h"
namespace itk
{
template <typename TInputImage, typename TOutputImage>
void
VnlInverse1DFFTImageFilter<TInputImage, TOutputImage>::GenerateData()
{
this->AllocateOutputs();
// get pointers to the input and output
const typename Superclass::InputImageType * input = this->GetInput();
typename Superclass::OutputImageType * output = this->GetOutput();
const typename Superclass::InputImageType::SizeType & inputSize = input->GetRequestedRegion().GetSize();
const unsigned int direction = this->GetDirection();
unsigned int vectorSize = inputSize[direction];
MultiThreaderBase * multiThreader = this->GetMultiThreader();
multiThreader->SetNumberOfWorkUnits(this->GetNumberOfWorkUnits());
multiThreader->template ParallelizeImageRegionRestrictDirection<TOutputImage::ImageDimension>(
direction,
output->GetRequestedRegion(),
[input, output, direction, vectorSize](const typename OutputImageType::RegionType & lambdaRegion) {
using InputIteratorType = ImageLinearConstIteratorWithIndex<InputImageType>;
using OutputIteratorType = ImageLinearIteratorWithIndex<OutputImageType>;
InputIteratorType inputIt(input, lambdaRegion);
OutputIteratorType outputIt(output, lambdaRegion);
inputIt.SetDirection(direction);
outputIt.SetDirection(direction);
using OutputPixelType = typename TOutputImage::PixelType;
vnl_vector<std::complex<OutputPixelType>> inputBuffer(vectorSize);
typename vnl_vector<std::complex<OutputPixelType>>::iterator inputBufferIt = inputBuffer.begin();
// fft is done in-place
typename vnl_vector<std::complex<OutputPixelType>>::iterator outputBufferIt = inputBuffer.begin();
vnl_fft_1d<OutputPixelType> v1d(vectorSize);
// for every fft line
for (inputIt.GoToBegin(), outputIt.GoToBegin(); !inputIt.IsAtEnd(); outputIt.NextLine(), inputIt.NextLine())
{
// copy the input line into our buffer
inputIt.GoToBeginOfLine();
inputBufferIt = inputBuffer.begin();
while (!inputIt.IsAtEndOfLine())
{
*inputBufferIt = inputIt.Get();
++inputIt;
++inputBufferIt;
}
// do the transform
v1d.fwd_transform(inputBuffer);
// copy the output from the buffer into our line
outputBufferIt = inputBuffer.begin();
outputIt.GoToBeginOfLine();
while (!outputIt.IsAtEndOfLine())
{
outputIt.Set(outputBufferIt->real() / vectorSize);
++outputIt;
++outputBufferIt;
}
}
},
this);
}
} // end namespace itk
#endif
|
