Multiply Image by Scalar

Synopsis

Multiply one image by a given scalar value.

Results

Input image

Output image

Code

C++

#include "itkImageFileReader.h"
#include "itkImageFileWriter.h"
#include "itkMultiplyImageFilter.h"

int
main(int argc, char * argv[])
{
  if (argc != 4)
  {
    std::cerr << "Usage: " << std::endl;
    std::cerr << argv[0];
    std::cerr << " <InputFileName> <Factor> <OutputFileName>";
    std::cerr << std::endl;
    return EXIT_FAILURE;
  }

  const char *           inputFileName = argv[1];
  const double           factor = std::stod(argv[2]);
  const char *           outputFileName = argv[3];
  constexpr unsigned int Dimension = 2;

  using InputPixelType = unsigned char;
  using InputImageType = itk::Image<InputPixelType, Dimension>;

  using ReaderType = itk::ImageFileReader<InputImageType>;
  ReaderType::Pointer reader = ReaderType::New();
  reader->SetFileName(inputFileName);

  using OutputPixelType = double;
  using OutputImageType = itk::Image<OutputPixelType, Dimension>;

  using FilterType = itk::MultiplyImageFilter<InputImageType, InputImageType, OutputImageType>;
  FilterType::Pointer filter = FilterType::New();
  filter->SetInput(reader->GetOutput());
  filter->SetConstant(factor);

  using WriterType = itk::ImageFileWriter<OutputImageType>;
  WriterType::Pointer writer = WriterType::New();
  writer->SetFileName(outputFileName);
  writer->SetInput(filter->GetOutput());

  try
  {
    writer->Update();
  }
  catch (itk::ExceptionObject & error)
  {
    std::cerr << "Error: " << error << std::endl;
    return EXIT_FAILURE;
  }

  return EXIT_SUCCESS;
}

Classes demonstrated

template<typename TInputImage1, typename TInputImage2 = TInputImage1, typename TOutputImage = TInputImage1>
class MultiplyImageFilter : public itk::BinaryGeneratorImageFilter<TInputImage1, TInputImage2, TOutputImage>

Pixel-wise multiplication of two images.

This class is templated over the types of the two input images and the type of the output image. Numeric conversions (castings) are done by the C++ defaults.

ITK Sphinx Examples:

• All ITK Sphinx Examples

• Multiply Two Images

• Multiply Image By Scalar

See itk::MultiplyImageFilter for additional documentation.