ITK  4.9.0
Insight Segmentation and Registration Toolkit
WikiExamples/SimpleOperations/Transparency.cxx
#include "itkImage.h"
#include "itkTIFFImageIO.h"
#include "itkRGBAPixel.h"
int main(int argc, char *argv[])
{
std::string outputFilename;
if(argc > 1)
{
outputFilename = argv[1];
}
else
{
outputFilename = "test.tif";
}
typedef itk::RGBAPixel<unsigned char> PixelType;
typedef itk::Image< PixelType, 2> ImageType;
ImageType::RegionType region;
ImageType::IndexType start;
start[0] = 0;
start[1] = 0;
ImageType::SizeType size;
size[0] = 200;
size[1] = 300;
region.SetSize(size);
region.SetIndex(start);
ImageType::Pointer image = ImageType::New();
image->SetRegions(region);
image->Allocate();
itk::ImageRegionIterator<ImageType> imageIterator(image,region);
while(!imageIterator.IsAtEnd())
{
ImageType::PixelType pixel = imageIterator.Get();
if(imageIterator.GetIndex()[0] > 100)
{
pixel.SetRed(0);
pixel.SetGreen(255);
pixel.SetBlue(0);
//pixel.SetAlpha(255); // invisible
pixel.SetAlpha(122);
}
else
{
pixel.SetRed(255);
pixel.SetGreen(0);
pixel.SetBlue(0);
pixel.SetAlpha(0.5);
}
imageIterator.Set(pixel);
++imageIterator;
}
typedef itk::TIFFImageIO TIFFIOType;
WriterType::Pointer writer = WriterType::New();
TIFFIOType::Pointer tiffIO = TIFFIOType::New();
tiffIO->SetPixelType(itk::ImageIOBase::RGBA);
writer->SetFileName(outputFilename);
writer->SetInput(image);
writer->SetImageIO(tiffIO);
writer->Update();
return EXIT_SUCCESS;
}