Function TestWriteToMemory

IO/Image/Testing/Cxx/TestWriteToMemory.cxx:18–87

#include <iostream>

int TestWriteToMemory(int argc, char* argv[])
{
  if (argc <= 1)
  {
    std::cout << "Usage: " << argv[0] << " <output file name>" << std::endl;
    return EXIT_FAILURE;
  }

  int extent[6] = { 0, 99, 0, 99, 0, 0 };
  vtkSmartPointer<vtkImageCanvasSource2D> imageSource =
    vtkSmartPointer<vtkImageCanvasSource2D>::New();
  imageSource->SetExtent(extent);
  imageSource->SetScalarTypeToUnsignedChar();
  imageSource->SetNumberOfScalarComponents(3);
  imageSource->SetDrawColor(127, 45, 255);
  imageSource->FillBox(0, 99, 0, 99);
  imageSource->SetDrawColor(255, 255, 255);
  imageSource->FillBox(40, 70, 20, 50);
  imageSource->Update();

  vtkSmartPointer<vtkImageCast> castFilter = vtkSmartPointer<vtkImageCast>::New();
  castFilter->SetOutputScalarTypeToUnsignedChar();
  castFilter->SetInputConnection(imageSource->GetOutputPort());
  castFilter->Update();

  vtkSmartPointer<vtkImageWriter> writer;

  std::string filename = argv[1];
  std::string fileext = filename.substr(filename.find_last_of('.') + 1);

  // Delete any existing files to prevent false failures
  if (vtksys::SystemTools::FileExists(filename))
  {
    vtksys::SystemTools::RemoveFile(filename);
  }

  if (fileext == "png")
  {
    vtkSmartPointer<vtkPNGWriter> pngWriter = vtkSmartPointer<vtkPNGWriter>::New();
    pngWriter->WriteToMemoryOn();
    writer = pngWriter;
  }
  else if (fileext == "jpeg" || fileext == "jpg")
  {
    vtkSmartPointer<vtkJPEGWriter> jpgWriter = vtkSmartPointer<vtkJPEGWriter>::New();
    jpgWriter->WriteToMemoryOn();
    writer = jpgWriter;
  }
  else if (fileext == "bmp")
  {
    vtkSmartPointer<vtkBMPWriter> bmpWriter = vtkSmartPointer<vtkBMPWriter>::New();
    bmpWriter->WriteToMemoryOn();
    writer = bmpWriter;
  }

  writer->SetFileName(filename.c_str());
  writer->SetInputConnection(castFilter->GetOutputPort());
  writer->Update();