ITK  5.3.0
Insight Toolkit
SphinxExamples/src/Numerics/Statistics/ComputeHistogramFromGrayscaleImage/Code.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 "itkImage.h"
int
main(int argc, char * argv[])
{
if (argc != 3)
{
std::cerr << argv[0] << "InputFileName NumberOfBins" << std::endl;
return EXIT_FAILURE;
}
constexpr unsigned int Dimension = 2;
using PixelType = unsigned char;
constexpr unsigned int MeasurementVectorSize = 1; // Grayscale
const auto binsPerDimension = static_cast<unsigned int>(std::stoi(argv[2]));
ImageType::Pointer image = itk::ReadImage<ImageType>(argv[1]);
using ImageToHistogramFilterType = itk::Statistics::ImageToHistogramFilter<ImageType>;
ImageToHistogramFilterType::HistogramType::MeasurementVectorType lowerBound(binsPerDimension);
lowerBound.Fill(0);
ImageToHistogramFilterType::HistogramType::MeasurementVectorType upperBound(binsPerDimension);
upperBound.Fill(255);
size.Fill(binsPerDimension);
ImageToHistogramFilterType::Pointer imageToHistogramFilter = ImageToHistogramFilterType::New();
imageToHistogramFilter->SetInput(image);
imageToHistogramFilter->SetHistogramBinMinimum(lowerBound);
imageToHistogramFilter->SetHistogramBinMaximum(upperBound);
imageToHistogramFilter->SetHistogramSize(size);
try
{
imageToHistogramFilter->Update();
}
catch (itk::ExceptionObject & error)
{
std::cerr << "Error: " << error << std::endl;
return EXIT_FAILURE;
}
ImageToHistogramFilterType::HistogramType * histogram = imageToHistogramFilter->GetOutput();
std::cout << "Frequency = [ ";
for (unsigned int i = 0; i < histogram->GetSize()[0]; ++i)
{
std::cout << histogram->GetFrequency(i);
if (i != histogram->GetSize()[0] - 1)
{
std::cout << "," << std::endl;
}
}
std::cout << " ]" << std::endl;
return EXIT_SUCCESS;
}
itkImageToHistogramFilter.h
itkImageRandomIteratorWithIndex.h
itkImageFileReader.h
itk::GTest::TypedefsAndConstructors::Dimension2::SizeType
ImageBaseType::SizeType SizeType
Definition: itkGTestTypedefsAndConstructors.h:49
itkImage.h
itk::Image
Templated n-dimensional image class.
Definition: itkImage.h:88
itk::Statistics::ImageToHistogramFilter
This class generates a histogram from an image.
Definition: itkImageToHistogramFilter.h:50
itk::GTest::TypedefsAndConstructors::Dimension2::Dimension
constexpr unsigned int Dimension
Definition: itkGTestTypedefsAndConstructors.h:44