MetadataExample.cxx

/*=========================================================================

  Program:   ORFEO Toolbox
  Language:  C++
  Date:      $Date$
  Version:   $Revision$


  Copyright (c) Centre National d'Etudes Spatiales. All rights reserved.
  See OTBCopyright.txt for details.


     This software is distributed WITHOUT ANY WARRANTY; without even 
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 
     PURPOSE.  See the above copyright notices for more information.

=========================================================================*/

#if defined(_MSC_VER)
#pragma warning ( disable : 4786 )
#endif

//  SoftwareGuide: BeginLatex
//
//  This example illustrates the access to metadata image information
//  with OTB. By metadata, we mean data which is typically stored with
//  remote sensing images, like geographical coordinates of pixels,
//  pixel spacing or resolution, etc. Of course, the availability of
//  these data depends on the image format used and on the fact that
//  the image producer must fill the available metadata fields. The
//  image formats which typically support metadata are for example
//  CEOS and GeoTiff.
//
//  The metadata support is embedded in OTB's IO functionnalities and
//  is accessible through the \doxygen{otb::Image} and
//  \doxygen{otb::VectorImage} classes. You should avoid using the
//  \doxygen{itk::Image} class if you want to have metadata support.
//
//  SoftwareGuide: EndLatex


#include "itkExceptionObject.h"
#include <iostream>
#include <fstream>
#include <string>

#include "otbImage.h"
#include "otbImageFileReader.h"


int main(int argc, char* argv[])
{

  // Verify the number of parameters in the command line
  const char * inputFilename  = argv[1];
  const char * outputAsciiFilename  = argv[2];

//  SoftwareGuide: BeginLatex
//
//  This simple example will consist on reading an image from a file
//  and writing the metadata to an output ASCII file. As usual we
//  start by defining the types needed for the image to be read.
//
//  SoftwareGuide: EndLatex

//  SoftwareGuide: BeginCodeSnippet	

  typedef unsigned char  	                        InputPixelType;
  const   unsigned int        	                        Dimension = 2;


  typedef otb::Image< InputPixelType,  Dimension >      InputImageType;
        
  typedef otb::ImageFileReader< InputImageType >        ReaderType;
//  SoftwareGuide: EndCodeSnippet
//  SoftwareGuide: BeginLatex
//
//  We can now instantiate the reader and get a pointer to the input image.
//
//  SoftwareGuide: EndLatex

//  SoftwareGuide: BeginCodeSnippet	
	

  ReaderType::Pointer reader = ReaderType::New();
  InputImageType::Pointer image = InputImageType::New();
 
  reader->SetFileName( inputFilename  );
  reader->Update();

  image = reader->GetOutput();

//  SoftwareGuide: EndCodeSnippet
//  SoftwareGuide: BeginLatex
//
//  Once the image has been read, we can access the metadata
//  information. We will copy this information to an ASCII file, so we
//  create an output file stream for this purpose.
//
//  SoftwareGuide: EndLatex

//  SoftwareGuide: BeginCodeSnippet	
	

  std::ofstream file;
	
  file.open(outputAsciiFilename);

//  SoftwareGuide: EndCodeSnippet
//  SoftwareGuide: BeginLatex
//
//  We can now call the different available methods for accessing the
//  metadata. Useful methods are :
//	\begin{itemize}
//      \item \code{GetSpacing}: the sampling step;
//      \item \code{GetOrigin}: the coordinates of the origin of the image;
//      \item \code{GetProjectionRef}: the image projection reference;
//      \item \code{GetGCPProjection}: the projection for the eventual
//  ground control points;
//      \item \code{GetGCPCount}: the number of GCPs available;
//	\end{itemize}	
//
//  SoftwareGuide: EndLatex

//  SoftwareGuide: BeginCodeSnippet	
	
	
  file << "Spacing " << image->GetSpacing() << std::endl;
  file << "Origin " << image->GetOrigin() << std::endl;
	
  file << "Projection REF " << image->GetProjectionRef() << std::endl;
		 
  file << "GCP Projection " << image->GetGCPProjection() << std::endl;
	
  unsigned int GCPCount = image->GetGCPCount();	
  file << "GCP Count " << image->GetGCPCount() << std::endl; 

//  SoftwareGuide: EndCodeSnippet
//  SoftwareGuide: BeginLatex
//
//  One can also get the GCPs by number, as well as their coordinates
//  in image and geographical space.
//
//  SoftwareGuide: EndLatex

//  SoftwareGuide: BeginCodeSnippet	
	
  for(unsigned int GCPnum = 0 ; GCPnum < GCPCount ; GCPnum++ )
    {
    file << "GCP[" << GCPnum << "] Id " << image->GetGCPId(GCPnum) << std::endl;
    file << "GCP[" << GCPnum << "] Info " << image->GetGCPInfo(GCPnum) << std::endl;
    file << "GCP[" << GCPnum << "] Row " << image->GetGCPRow(GCPnum) << std::endl;
    file << "GCP[" << GCPnum << "] Col " << image->GetGCPCol(GCPnum) << std::endl;
    file << "GCP[" << GCPnum << "] X " << image->GetGCPX(GCPnum) << std::endl;
    file << "GCP[" << GCPnum << "] Y " << image->GetGCPY(GCPnum) << std::endl;
    file << "GCP[" << GCPnum << "] Z " << image->GetGCPZ(GCPnum) << std::endl;
    file << "----------------" << std::endl;
    }

//  SoftwareGuide: EndCodeSnippet
//  SoftwareGuide: BeginLatex
//
//  If a geographical transformation is available, it can be recovered
//  as follows.
//
//  SoftwareGuide: EndLatex

//  SoftwareGuide: BeginCodeSnippet	
	
  InputImageType::VectorType tab = image->GetGeoTransform();

  file << "Geo Transform " << std::endl;
  for(int i = 0 ; i < tab.size() ; i++ )
    {
    file << " " <<i<<" -> "<<tab[i]<< std::endl;
    }
  tab.clear();
	
  tab = image->GetUpperLeftCorner();
  file << "Corners " << std::endl;
  for(int i = 0 ; i < tab.size() ; i++ )
    {
    file << " UL[" <<i<<"] -> "<<tab[i]<< std::endl;
    }
  tab.clear();
		
  tab = image->GetUpperRightCorner();
  for(int i = 0 ; i < tab.size() ; i++ )
    {
    file << " UR[" <<i<<"] -> "<<tab[i]<< std::endl;
    }
  tab.clear();
		
  tab = image->GetLowerLeftCorner();
  for(int i = 0 ; i < tab.size() ; i++ )
    {
    file << " LL[" <<i<<"] -> "<<tab[i]<< std::endl;
    }
  tab.clear();
			
  tab = image->GetLowerRightCorner();
  for(int i = 0 ; i < tab.size() ; i++ )
    {
    file << " LR[" <<i<<"] -> "<<tab[i]<< std::endl;
    }	
  tab.clear();
		
  file.close();
	
  //  SoftwareGuide: EndCodeSnippet
  return EXIT_SUCCESS;
}