ITK  4.8.0
Insight Segmentation and Registration Toolkit
Examples/Filtering/SpatialObjectToImage3.cxx
/*=========================================================================
*
* Copyright Insight Software Consortium
*
* 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.
*
*=========================================================================*/
// Software Guide : BeginLatex
//
// This example illustrates the use of the
// \doxygen{PolygonSpatialObject} for generating a binary image through the
// \doxygen{SpatialObjectToImageFilter}.
//
// \index{itk::PolygonSpatialObject|textbf}
// \index{itk::SpatialObjectToImageFilter|textbf}
//
// We start by including the header of the PolygonSpatialObject that we will
// use as elementary shape, and the header for the SpatialObjectToImageFilter
// that we will use to rasterize the SpatialObject.
//
// \index{itk::PolygonSpatialObject!header}
// \index{itk::SpatialObjectToImageFilter!header}
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
// Software Guide : EndCodeSnippet
int main( int argc, char *argv[] )
{
if( argc != 2 )
{
std::cerr << "Usage: " << argv[0] << " outputimagefile " << std::endl;
return EXIT_FAILURE;
}
// Software Guide : BeginLatex
//
// We declare the pixel type and dimension of the image to be produced as
// output.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
typedef unsigned char PixelType;
const unsigned int Dimension = 3;
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Using the same dimension, we instantiate the types of the elementary
// SpatialObjects that we plan to rasterize.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// We instantiate the SpatialObjectToImageFilter type by using as template
// arguments the input SpatialObject and the output image types.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
PolygonType, ImageType > SpatialObjectToImageFilterType;
SpatialObjectToImageFilterType::Pointer imageFilter =
SpatialObjectToImageFilterType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// The SpatialObjectToImageFilter requires that the user defines the grid
// parameters of the output image. This includes the number of pixels along
// each dimension, the pixel spacing, image direction and
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
ImageType::SizeType size;
size[ 0 ] = 100;
size[ 1 ] = 100;
size[ 2 ] = 1;
imageFilter->SetSize( size );
// Software Guide : EndCodeSnippet
// Software Guide : BeginCodeSnippet
ImageType::SpacingType spacing;
spacing[0] = 100.0 / size[0];
spacing[1] = 100.0 / size[1];
spacing[2] = 1.0;
imageFilter->SetSpacing( spacing );
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// We create the polygon object.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
PolygonType::Pointer polygon = PolygonType::New();
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// We populate the points of the polygon by computing the edges of a
// hexagon centered in the image.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
const unsigned int numberOfPoints = 6;
PolygonType::PointType point;
PolygonType::PointType::VectorType radial;
radial[0] = 0.0;
radial[1] = 0.0;
radial[2] = 0.0;
PolygonType::PointType center;
center[0] = 50.0;
center[1] = 50.0;
center[2] = 0.0;
const double radius = 40.0;
for( unsigned int i=0; i < numberOfPoints; i++ )
{
const double angle = 2.0 * vnl_math::pi * i / numberOfPoints;
radial[0] = radius * std::cos( angle );
radial[1] = radius * std::sin( angle );
point = center + radial;
polygon->AddPoint( point );
}
// Software Guide : EndCodeSnippet
std::cout << "Polygon Perimeter = " << polygon->MeasurePerimeter() << std::endl;
std::cout << "Polygon Area = " << polygon->MeasureArea() << std::endl;
// Software Guide : BeginLatex
//
// We connect the polygon as the input to the SpatialObjectToImageFilter.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
imageFilter->SetInput( polygon );
// Software Guide : EndCodeSnippet
// Software Guide : BeginLatex
//
// Finally we are ready to run the filter. We use the typical invocation of
// the \code{Update} method, and we instantiate an \code{ImageFileWriter} in
// order to save the generated image into a file.
//
// Software Guide : EndLatex
// Software Guide : BeginCodeSnippet
WriterType::Pointer writer = WriterType::New();
writer->SetFileName( argv[1] );
writer->SetInput( imageFilter->GetOutput() );
try
{
imageFilter->Update();
writer->Update();
}
catch( itk::ExceptionObject & excp )
{
std::cerr << excp << std::endl;
return EXIT_FAILURE;
}
// Software Guide : EndCodeSnippet
return EXIT_SUCCESS;
}