SimpleITK  
SliceBySliceDecorator/SliceBySliceDecorator.cxx
/*=========================================================================
*
* 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
*
* http://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 "SimpleITK.h"
#include <cstdlib>
#include <iostream>
namespace sitk = itk::simple;
using itk::simple::operator<<;
// Forward declaration to specialize the implementation with the function's
// argument and returns types.
template <class T>
struct SliceBySliceDecorator;
/* \brief A function decorator to adapt an function to process an image as a
* sequence of 2D (slices or) images.
*
* For ease of use the makeSliceBySlice procedure should be used to construct
* the SliceBySliceDecorator.
*
* The overloaded function call operator(), enable objects to be used as
* functions.
*
* The return image is the first argument modified with the slice by slice
* results of the f function.
*/
template <class R, class ImageArg, class... Args>
struct SliceBySliceDecorator<R(ImageArg, Args...)>
{
using FunctionType = std::function<R(ImageArg, Args...)>;
explicit SliceBySliceDecorator(FunctionType f)
: f_(std::move(f))
{}
R
operator()(sitk::Image & image, Args... args)
{
const auto image_size = image.GetSize();
unsigned int dim = image.GetDimension();
if (dim <= iter_dim)
{
// If no sub-dimension extraction is required then directly run the
// function on the input and replace it.
image = f_(image, args...);
return image;
}
std::vector<unsigned int> extract_size = image.GetSize();
std::fill(extract_size.begin() + iter_dim, extract_size.end(), 0);
std::vector<int> extract_index(dim, 0);
// The extract filter is used to extract a 2D image from the higher
// dimensional input image.
extractor.SetSize(extract_size);
// The paste filter places the processed slice back into the original image
// at the same location where the extraction occurred. The default
// value of DestinationSkipAxes is [ false, false, true, ... ], which is
// correct for the situation of preserving the first dimensions and
// collapsing the remainder.
paster.SetSourceSize(std::vector<unsigned int>(extract_size.begin(), extract_size.begin() + iter_dim));
while (static_cast<unsigned int>(extract_index.back()) < image.GetSize().back())
{
extractor.SetIndex(extract_index);
// Store the results of the function as a r-value, so that the
// paste filter will run "in place" and reuse the buffer for output.
sitk::Image && temp_image = f_(extractor.Execute(image), args...);
paster.SetDestinationIndex(extract_index);
image = paster.Execute(image, temp_image);
// increment extraction index
++extract_index[iter_dim];
for (unsigned int e = iter_dim; e + 1 < dim; ++e)
{
// if the index element is beyond the size, propagate to next element.
if (static_cast<unsigned int>(extract_index[e]) > image.GetSize()[e])
{
extract_index[e] = 0;
++extract_index[e + 1];
}
}
}
return image;
}
FunctionType f_;
constexpr static unsigned int iter_dim = 2;
};
template <class R, class... Args>
SliceBySliceDecorator<R(Args...)> makeSliceBySlice(R (*f)(Args...))
{
using DecoratorType = SliceBySliceDecorator<R(Args...)>;
return DecoratorType(typename DecoratorType::FunctionType(f));
}
int
main(int argc, char * argv[])
{
if (argc < 3)
{
std::cerr << "Usage: " << argv[0] << " <inputImage> <outputImage>" << std::endl;
return 1;
}
sitk::Image tempImage = sitk::ReadImage(argv[1]);
// The parameters to the filter are hard coded to simplify the example.
float alpha = 0.3f;
float beta = 0.3f;
std::vector<unsigned int> radius(2, 20);
// The return type of the function decorator is complex, so the auto type is
// used for brevity.
auto AdaptiveHistogramEqualization2D = makeSliceBySlice(sitk::AdaptiveHistogramEqualization);
// Execute the decorated function.
tempImage = AdaptiveHistogramEqualization2D(tempImage, radius, alpha, beta);
sitk::WriteImage(tempImage, argv[2]);
return 0;
}
itk::simple::Image
The Image class for SimpleITK.
Definition: sitkImage.h:76
itk::simple::Image::GetSize
std::vector< unsigned int > GetSize() const
SimpleITK.h
itk::simple::ReadImage
SITKIO_EXPORT Image ReadImage(const PathType &filename, PixelIDValueEnum outputPixelType=sitkUnknown, const std::string &imageIO="")
ReadImage is a procedural interface to the ImageFileReader class which is convenient for most image r...
itk::simple::PasteImageFilter::Execute
Image Execute(Image &&destinationImage, const Image &sourceImage)
itk::simple::AdaptiveHistogramEqualization
Image AdaptiveHistogramEqualization(const Image &image1, std::vector< unsigned int > radius=std::vector< unsigned int >(3, 5), float alpha=0.3f, float beta=0.3f)
Power Law Adaptive Histogram Equalization.
itk::simple::ExtractImageFilter
Decrease the image size by cropping the image to the selected region bounds.
Definition: sitkExtractImageFilter.h:72
itk::simple::Image::GetDimension
unsigned int GetDimension() const
itk::simple::ExtractImageFilter::Execute
Image Execute(Image &&image1)
itk::simple::WriteImage
SITKIO_EXPORT void WriteImage(const Image &image, const PathType &fileName, bool useCompression=false, int compressionLevel=-1)
WriteImage is a procedural interface to the ImageFileWriter. class which is convenient for many image...
itk::simple::PasteImageFilter
Paste an image (or a constant value) into another image.
Definition: sitkPasteImageFilter.h:55
sitkExtractImageFilter.h
itk::simple::PasteImageFilter::SetDestinationIndex
Self & SetDestinationIndex(std::vector< int > DestinationIndex)
Definition: sitkPasteImageFilter.h:109
itk::simple::ExtractImageFilter::SetIndex
Self & SetIndex(std::vector< int > Index)
Set the starting index of the input image to extract.
Definition: sitkExtractImageFilter.h:114
itk::simple::ExtractImageFilter::SetSize
Self & SetSize(std::vector< unsigned int > Size)
Set the size of the region to extract.
Definition: sitkExtractImageFilter.h:95
itk::simple::PasteImageFilter::SetSourceSize
Self & SetSourceSize(std::vector< unsigned int > SourceSize)
Definition: sitkPasteImageFilter.h:74
itk::simple
Definition: sitkAdditionalProcedures.h:28