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

  Program:   Visualization Toolkit
  Module:    vtkTIFFReader.cxx,v

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm 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 notice for more information.

=========================================================================*/
#include "vtkTIFFReader.h"

#include "vtkDataArray.h"
#include "vtkImageData.h"
#include "vtkPointData.h"
#include "vtkErrorCode.h"
#include "vtkObjectFactory.h"

#include <sys/stat.h>
#include <string>

extern "C" {
#include "vtk_tiff.h"
}

//-------------------------------------------------------------------------
vtkStandardNewMacro(vtkTIFFReader)

class vtkTIFFReader::vtkTIFFReaderInternal
{
public:
  vtkTIFFReaderInternal();
  bool Initialize();
  void Clean();
  bool CanRead();
  bool Open(const char *filename);
  TIFF *Image;
  bool IsOpen;
  unsigned int Width;
  unsigned int Height;
  unsigned short NumberOfPages;
  unsigned short CurrentPage;
  unsigned short SamplesPerPixel;
  unsigned short Compression;
  unsigned short BitsPerSample;
  unsigned short Photometrics;
  bool HasValidPhotometricInterpretation;
  unsigned short PlanarConfig;
  unsigned short Orientation;
  unsigned long int TileDepth;
  unsigned int TileRows;
  unsigned int TileColumns;
  unsigned int TileWidth;
  unsigned int TileHeight;
  unsigned short NumberOfTiles;
  unsigned int SubFiles;
  unsigned int ResolutionUnit;
  float XResolution;
  float YResolution;
  short SampleFormat;
  static void ErrorHandler(const char* module, const char* fmt, va_list ap);
};

extern "C" {
static void vtkTIFFReaderInternalErrorHandler(const char* vtkNotUsed(module),
                                              const char* vtkNotUsed(fmt),
                                              va_list vtkNotUsed(ap))
{
  // Do nothing
  // Ignore errors
}
}

//-------------------------------------------------------------------------
bool vtkTIFFReader::vtkTIFFReaderInternal::Open(const char *filename)
{
  this->Clean();
  struct stat fs;
  if (stat(filename, &fs))
    {
    return false;
    }
  this->Image = TIFFOpen(filename, "r");
  if (!this->Image)
    {
    this->Clean();
    return false;
    }
  if (!this->Initialize())
    {
    this->Clean();
    return false;
    }

  this->IsOpen = true;
  return true;
}

//-------------------------------------------------------------------------
void vtkTIFFReader::vtkTIFFReaderInternal::Clean()
{
  if (this->Image)
    {
    TIFFClose(this->Image);
    this->Image = NULL;
    }
  this->Width = 0;
  this->Height = 0;
  this->SamplesPerPixel = 0;
  this->Compression = 0;
  this->BitsPerSample = 0;
  this->Photometrics = 0;
  this->HasValidPhotometricInterpretation = false;
  this->PlanarConfig = 0;
  this->TileDepth = 0;
  this->CurrentPage = 0;
  this->NumberOfPages = 0;
  this->NumberOfTiles = 0;
  this->TileRows = 0;
  this->TileColumns = 0;
  this->TileWidth = 0;
  this->TileHeight = 0;
  this->XResolution = 1;
  this->YResolution = 1;
  this->SubFiles = 0;
  this->SampleFormat = 1;
  this->ResolutionUnit = 1; // none
  this->IsOpen = false;
}

//-------------------------------------------------------------------------
vtkTIFFReader::vtkTIFFReaderInternal::vtkTIFFReaderInternal()
{
  this->Image           = NULL;
  TIFFSetErrorHandler(&vtkTIFFReaderInternalErrorHandler);
  TIFFSetWarningHandler(&vtkTIFFReaderInternalErrorHandler);
  this->Clean();
}

//-------------------------------------------------------------------------
bool vtkTIFFReader::vtkTIFFReaderInternal::Initialize()
{
  if (this->Image)
    {
    if (!TIFFGetField(this->Image, TIFFTAG_IMAGEWIDTH, &this->Width) ||
        !TIFFGetField(this->Image, TIFFTAG_IMAGELENGTH, &this->Height))
      {
      return false;
      }

    // Get the resolution in each direction
    TIFFGetField(this->Image, TIFFTAG_XRESOLUTION, &this->XResolution);
    TIFFGetField(this->Image, TIFFTAG_YRESOLUTION, &this->YResolution);
    TIFFGetField(this->Image, TIFFTAG_RESOLUTIONUNIT, &this->ResolutionUnit);

    // Check the number of pages. First by looking at the number of directories.
    this->NumberOfPages = TIFFNumberOfDirectories(this->Image);

    if (this->NumberOfPages == 0)
      {
      if (!TIFFGetField(this->Image, TIFFTAG_PAGENUMBER, &this->CurrentPage,
                        &this->NumberOfPages))
        {
        // Check the Image Description tag to know the number of images
        // This is used by ImageJ
        char** description = new char*[255];
        if (TIFFGetField(this->Image, TIFFTAG_IMAGEDESCRIPTION, description))
          {
          // look for the number of images
          std::string desc = description[0];
          int pos = desc.find("images=");
          int pos2 = desc.find("\n");
          if ((pos != -1) && (pos2 != -1))
            {
            this->NumberOfPages = atoi(desc.substr(pos+7,pos2-pos-7).c_str());
            }
          }
        }
      }

    // If the number of pages is still zero we look if the image is tiled.
    if (this->NumberOfPages == 0 && TIFFIsTiled(this->Image))
      {
      this->NumberOfTiles = TIFFNumberOfTiles(this->Image);

      if (!TIFFGetField(this->Image, TIFFTAG_TILEWIDTH, &this->TileWidth) ||
          !TIFFGetField(this->Image, TIFFTAG_TILELENGTH, &this->TileHeight)
        )
        {
        cerr << "Cannot read tile width and tile length from file" << endl;
        }
      else
        {
        TileRows = this->Height / this->TileHeight;
        TileColumns = this->Width / this->TileWidth;
        }
      }

    // Checking if the TIFF contains subfiles
    if (this->NumberOfPages > 1)
      {
      this->SubFiles = 0;

      for (unsigned int page = 0; page<this->NumberOfPages; ++page)
        {
        long subfiletype = 6;
        if (TIFFGetField(this->Image, TIFFTAG_SUBFILETYPE, &subfiletype))
          {
          if (subfiletype == 0)
            {
            this->SubFiles += 1;
            }
          }
        TIFFReadDirectory(this->Image);
        }

      // Set the directory to the first image
      TIFFSetDirectory(this->Image, 0);
      }

      // TIFFTAG_ORIENTATION tag from the image data and use it if available.
      // If the tag is not found in the image data, use ORIENTATION_BOTLEFT by
      // default.
      int status = TIFFGetField(this->Image, TIFFTAG_ORIENTATION,
                                &this->Orientation);
      if (!status)
        {
        this->Orientation = ORIENTATION_BOTLEFT;
        }

    TIFFGetFieldDefaulted(this->Image, TIFFTAG_SAMPLESPERPIXEL,
                          &this->SamplesPerPixel);
    TIFFGetFieldDefaulted(this->Image, TIFFTAG_COMPRESSION, &this->Compression);
    TIFFGetFieldDefaulted(this->Image, TIFFTAG_BITSPERSAMPLE,
                          &this->BitsPerSample);
    TIFFGetFieldDefaulted(this->Image, TIFFTAG_PLANARCONFIG, &this->PlanarConfig);
    TIFFGetFieldDefaulted(this->Image, TIFFTAG_SAMPLEFORMAT, &this->SampleFormat);

    // If TIFFGetField returns false, there's no Photometric Interpretation
    // set for this image, but that's a required field so we set a warning flag.
    // (Because the "Photometrics" field is an enum, we can't rely on setting
    // this->Photometrics to some signal value.)
    if (TIFFGetField(this->Image, TIFFTAG_PHOTOMETRIC, &this->Photometrics))
      {
      this->HasValidPhotometricInterpretation = true;
      }
    else
      {
      this->HasValidPhotometricInterpretation = false;
      }
    if (!TIFFGetField(this->Image, TIFFTAG_TILEDEPTH, &this->TileDepth))
      {
      this->TileDepth = 0;
      }
    }

  return true;
}

//-------------------------------------------------------------------------
bool vtkTIFFReader::vtkTIFFReaderInternal::CanRead()
{
  return ( this->Image && ( this->Width > 0 ) && ( this->Height > 0 ) &&
           ( this->SamplesPerPixel > 0 ) &&
           ( this->Compression == COMPRESSION_NONE ||
             this->Compression == COMPRESSION_PACKBITS ||
             this->Compression == COMPRESSION_LZW
             ) &&
           ( this->HasValidPhotometricInterpretation ) &&
           ( this->Photometrics == PHOTOMETRIC_RGB ||
             this->Photometrics == PHOTOMETRIC_MINISWHITE ||
             this->Photometrics == PHOTOMETRIC_MINISBLACK ||
             this->Photometrics == PHOTOMETRIC_PALETTE ) &&
           ( this->PlanarConfig == PLANARCONFIG_CONTIG ) &&
           ( !this->TileDepth ) &&
           ( this->BitsPerSample == 8 || this->BitsPerSample == 16 ||
             this->BitsPerSample == 32) );
}

//-------------------------------------------------------------------------
vtkTIFFReader::vtkTIFFReader()
{

  this->Initialize();
  this->InternalImage = new vtkTIFFReader::vtkTIFFReaderInternal;
  this->OutputExtent[0] = 0;
  this->OutputExtent[1] = 0;
  this->OutputExtent[2] = 0;
  this->OutputExtent[3] = 0;
  this->OutputExtent[4] = 0;
  this->OutputExtent[5] = 0;
  this->OutputIncrements[0] = 0;
  this->OutputIncrements[1] = 0;
  this->OutputIncrements[2] = 0;

  this->OrientationTypeSpecifiedFlag = false;
  this->OriginSpecifiedFlag = false;
  this->SpacingSpecifiedFlag = false;

  //Make the default orientation type to be ORIENTATION_BOTLEFT
  this->OrientationType = 4;
}

//-------------------------------------------------------------------------
vtkTIFFReader::~vtkTIFFReader()
{
  delete this->InternalImage;
}

//-------------------------------------------------------------------------
void vtkTIFFReader::ExecuteInformation()
{
  this->Initialize();
  this->ComputeInternalFileName(this->DataExtent[4]);
  if (this->InternalFileName == NULL)
    {
    vtkErrorMacro("Need to specify a filename");
    this->SetErrorCode(vtkErrorCode::NoFileNameError);
    return;
    }

  if (!this->InternalImage->Open(this->InternalFileName))
    {
    vtkErrorMacro("Unable to open file " << this->InternalFileName);
    this->SetErrorCode(vtkErrorCode::CannotOpenFileError);
    this->DataExtent[0] = 0;
    this->DataExtent[1] = 0;
    this->DataExtent[2] = 0;
    this->DataExtent[3] = 0;
    this->DataExtent[4] = 0;
    this->DataExtent[5] = 0;
    this->SetNumberOfScalarComponents(1);
    this->vtkImageReader2::ExecuteInformation();
    return;
    }

  // If orientation information is provided, overwrite the value
  // read from the tiff image
  if (this->OrientationTypeSpecifiedFlag)
    {
    this->InternalImage->Orientation = OrientationType;
    }

  if (!SpacingSpecifiedFlag)
    {
    this->DataSpacing[0] = 1.0;
    this->DataSpacing[1] = 1.0;

    // If we have some spacing information we use it
    if (this->InternalImage->ResolutionUnit > 0 &&
        this->InternalImage->XResolution > 0 &&
        this->InternalImage->YResolution > 0)
      {
      if (this->InternalImage->ResolutionUnit == 2) // inches
        {
        this->DataSpacing[0] = 25.4 / this->InternalImage->XResolution;
        this->DataSpacing[1] = 25.4 / this->InternalImage->YResolution;
        }
      else if (this->InternalImage->ResolutionUnit == 3) // cm
        {
        this->DataSpacing[0] = 10.0 / this->InternalImage->XResolution;
        this->DataSpacing[1] = 10.0 / this->InternalImage->YResolution;
        }
      }
    }

  if (!OriginSpecifiedFlag)
    {
    this->DataOrigin[0] = 0.0;
    this->DataOrigin[1] = 0.0;
    }

  // Pull out the width/height, etc.
  this->DataExtent[0] = 0;
  this->DataExtent[1] = this->InternalImage->Width - 1;
  this->DataExtent[2] = 0;
  this->DataExtent[3] = this->InternalImage->Height - 1;

  switch (this->GetFormat())
    {
    case vtkTIFFReader::GRAYSCALE:
    case vtkTIFFReader::PALETTE_GRAYSCALE:
      this->SetNumberOfScalarComponents(1);
      break;
    case vtkTIFFReader::RGB:
      this->SetNumberOfScalarComponents(this->InternalImage->SamplesPerPixel);
      break;
    case vtkTIFFReader::PALETTE_RGB:
      this->SetNumberOfScalarComponents(3);
      break;
    default:
      this->SetNumberOfScalarComponents(4);
    }

  if (!this->InternalImage->CanRead())
    {
    this->SetNumberOfScalarComponents(4);
    }

  // Figure out the appropriate scalar type for the data.
  int scalarType = VTK_CHAR;
  short sampleFormat = this->InternalImage->SampleFormat;
  if (this->InternalImage->BitsPerSample <= 8)
    {
    scalarType = sampleFormat == 2 ? VTK_CHAR : VTK_UNSIGNED_CHAR;
    }
  else if (this->InternalImage->BitsPerSample <= 16)
    {
    scalarType = sampleFormat == 2 ? VTK_SHORT : VTK_UNSIGNED_SHORT;
    }
  else if (this->InternalImage->BitsPerSample <= 32 && sampleFormat <= 2)
    {
    scalarType = sampleFormat == 2 ? VTK_INT : VTK_UNSIGNED_INT;
    }
  else if (this->InternalImage->BitsPerSample <= 32 && sampleFormat == 3)
    {
    scalarType = VTK_FLOAT;
    }
  else
    {
    vtkErrorMacro("Unhandled Bit Per Sample: " << this->InternalImage->BitsPerSample);
    return;
    }
  this->SetDataScalarType(scalarType);

  // We check if we have a Zeiss image.
  // Meaning that the SamplesPerPixel is 2 but the image should be treated as
  // an RGB image.
  if (this->InternalImage->SamplesPerPixel == 2)
    {
    this->SetNumberOfScalarComponents(3);
    }

  // If the tiff file is multi-pages series of tiff images (3D volume)
  if (this->InternalImage->NumberOfPages > 1)
    {
    if (this->InternalImage->SubFiles > 0)
      {
      this->DataExtent[4] = 0;
      this->DataExtent[5] = this->InternalImage->SubFiles - 1;
      }
    else
      {
      this->DataExtent[4] = 0;
      this->DataExtent[5] = this->InternalImage->NumberOfPages - 1;
      }

    if (!SpacingSpecifiedFlag)
      {
      this->DataSpacing[2] = 1.0;
      }
    if (!OriginSpecifiedFlag)
      {
      this->DataOrigin[2]  = 0.0;
      }
    }

   // If the tiff is tiled
   if (this->InternalImage->NumberOfTiles > 1)
     {
     this->DataExtent[1]  = this->InternalImage->TileWidth;
     this->DataExtent[3]  = this->InternalImage->TileHeight;
     this->DataExtent[5]  = this->InternalImage->NumberOfTiles;
     if (!SpacingSpecifiedFlag)
       {
       this->DataSpacing[2] = 1.0;
       }
     if (!OriginSpecifiedFlag)
       {
       this->DataOrigin[2]  = 0.0;
       }
     }

  this->vtkImageReader2::ExecuteInformation();
  // Don't close the file yet, since we need the image internal
  // parameters such as NumberOfPages, NumberOfTiles to decide
  // how to read in the image.
}


// Set orientation type
//
//ORIENTATION_TOPLEFT         1       (row 0 top, col 0 lhs)
//ORIENTATION_TOPRIGHT        2       (row 0 top, col 0 rhs)
//ORIENTATION_BOTRIGHT        3       (row 0 bottom, col 0 rhs)
//ORIENTATION_BOTLEFT         4       (row 0 bottom, col 0 lhs)
//ORIENTATION_LEFTTOP         5       (row 0 lhs, col 0 top)
//ORIENTATION_RIGHTTOP        6       (row 0 rhs, col 0 top)
//ORIENTATION_RIGHTBOT        7       (row 0 rhs, col 0 bottom)
//ORIENTATION_LEFTBOT         8       (row 0 lhs, col 0 bottom) */
void vtkTIFFReader::SetOrientationType( unsigned int orientationType )
{
  if (orientationType < 1 || orientationType > 8)
    {
    vtkErrorMacro( "Invalid Orientation type specified" );
    return;
    }

  if (this->OrientationType != orientationType)
    {
    this->OrientationType = orientationType;
    this->Modified();
    }
  if (!this->OrientationTypeSpecifiedFlag)
    {
    this->Modified();
    }
  // To preserve backward compatibility OrientationTypeSpecifiedFlag would
  // always be set to true whatever user input...
  this->OrientationTypeSpecifiedFlag = true;
}

//-------------------------------------------------------------------------
template <class OT>
void vtkTIFFReader::Process2(OT *outPtr, int *)
{
  if (!this->InternalImage->Open(this->GetInternalFileName()))
    {
    return;
    }
  // if orientation information is provided, overwrite the value
  // read from the tiff image
  if (this->GetOrientationTypeSpecifiedFlag())
    {
    this->InternalImage->Orientation = this->GetOrientationType();
    }

  this->Initialize();
  this->ReadImageInternal(outPtr);

  // Close the file
  this->InternalImage->Clean();
}

//----------------------------------------------------------------------------
// This function reads in one data of data.
// templated to handle different data types.
template <class OT>
void vtkTIFFReader::Process(OT *outPtr, int outExtent[6], vtkIdType outIncr[3])
{
  // multiple number of pages
  if (this->InternalImage->NumberOfPages > 1)
    {
    this->ReadVolume(outPtr);
    return;
    }

  // tiled image
  if (this->InternalImage->NumberOfTiles > 0)
    {
    this->ReadTiles(outPtr);
    return;
    }

  // The input tiff dataset is neither multiple pages and nor
  // tiled. Hence close the image and start reading each TIFF
  // file
  this->InternalImage->Clean();

  OT *outPtr2 = outPtr;
  for (int idx2 = outExtent[4]; idx2 <= outExtent[5]; ++idx2)
    {
    this->ComputeInternalFileName(idx2);
    // read in a TIFF file
    this->Process2(outPtr2, outExtent);
    this->UpdateProgress((idx2 - outExtent[4])/
                         (outExtent[5] - outExtent[4] + 1.0));
    outPtr2 += outIncr[2];
    }
}


//----------------------------------------------------------------------------
// This function reads a data from a file.  The datas extent/axes
// are assumed to be the same as the file extent/order.
void vtkTIFFReader::ExecuteDataWithInformation(vtkDataObject *output,
                                                vtkInformation *outInfo)
{
  if (this->InternalFileName == NULL)
    {
    vtkErrorMacro("Either a FileName or FilePrefix must be specified.");
    return;
    }

  this->ComputeDataIncrements();

  // Get the data
  vtkImageData *data = this->AllocateOutputData(output, outInfo);
  data->GetExtent(this->OutputExtent);
  data->GetIncrements(this->OutputIncrements);

  // Call the correct templated function for the input
  void *outPtr = data->GetScalarPointer();

  switch (data->GetScalarType())
    {
    vtkTemplateMacro(this->Process((VTK_TT *)(outPtr),
                                  this->OutputExtent, this->OutputIncrements));
    default:
      vtkErrorMacro("UpdateFromFile: Unknown data type");
    }
  data->GetPointData()->GetScalars()->SetName("Tiff Scalars");
}

//----------------------------------------------------------------------------
unsigned int vtkTIFFReader::GetFormat()
{
  if (this->ImageFormat != vtkTIFFReader::NOFORMAT)
    {
    return this->ImageFormat;
    }

  switch (this->InternalImage->Photometrics)
    {
    case PHOTOMETRIC_RGB:
    case PHOTOMETRIC_YCBCR:
      this->ImageFormat = vtkTIFFReader::RGB;
      return this->ImageFormat;
    case PHOTOMETRIC_MINISWHITE:
    case PHOTOMETRIC_MINISBLACK:
      this->ImageFormat = vtkTIFFReader::GRAYSCALE;
      return this->ImageFormat;
    case PHOTOMETRIC_PALETTE:
      for (unsigned int cc = 0; cc < 256; ++cc)
        {
        unsigned short red, green, blue;
        this->GetColor(cc, &red, &green, &blue);
        if (red != green || red != blue)
          {
          this->ImageFormat = vtkTIFFReader::PALETTE_RGB;
          return this->ImageFormat;
          }
        }
      this->ImageFormat = vtkTIFFReader::PALETTE_GRAYSCALE;
      return this->ImageFormat;
     }
  this->ImageFormat = vtkTIFFReader::OTHER;
  return this->ImageFormat;
}

//----------------------------------------------------------------------------
void vtkTIFFReader::GetColor(int index, unsigned short *red,
                              unsigned short *green, unsigned short *blue)
{
  *red   = 0;
  *green = 0;
  *blue  = 0;
  if (index < 0)
    {
    vtkErrorMacro("Color index has to be greater than 0");
    return;
    }
  if (this->TotalColors > 0 &&
      this->ColorRed && this->ColorGreen && this->ColorBlue )
    {
    if (index >= this->TotalColors)
      {
      vtkErrorMacro("Color index has to be less than number of colors ("
                    << this->TotalColors << ")");
      return;
      }
    *red   = *(this->ColorRed   + index);
    *green = *(this->ColorGreen + index);
    *blue  = *(this->ColorBlue  + index);
    return;
    }

  unsigned short photometric;

  if (!TIFFGetField(this->InternalImage->Image, TIFFTAG_PHOTOMETRIC, &photometric))
    {
    if (this->InternalImage->Photometrics != PHOTOMETRIC_PALETTE)
      {
      vtkErrorMacro("You can only access colors for palette images");
      return;
      }
    }

  unsigned short *red_orig, *green_orig, *blue_orig;

  switch (this->InternalImage->BitsPerSample)
    {
    case 1: case 2: case 4:
    case 8: case 16:
      break;
    default:
      vtkErrorMacro( "Sorry, can not image with "
                     << this->InternalImage->BitsPerSample
                     << "-bit samples" );
      return;
    }
  if (!TIFFGetField(this->InternalImage->Image, TIFFTAG_COLORMAP,
                    &red_orig, &green_orig, &blue_orig))
    {
    vtkErrorMacro("Missing required \"Colormap\" tag");
    return;
    }
  this->TotalColors = (1L << this->InternalImage->BitsPerSample);

  if (index >= this->TotalColors)
    {
    vtkErrorMacro("Color index has to be less than number of colors ("
                  << this->TotalColors << ")");
    return;
    }
  this->ColorRed   =   red_orig;
  this->ColorGreen = green_orig;
  this->ColorBlue  =  blue_orig;

  *red   = *(red_orig   + index);
  *green = *(green_orig + index);
  *blue  = *(blue_orig  + index);
}

//-------------------------------------------------------------------------
void vtkTIFFReader::Initialize()
{
  this->ColorRed    = 0;
  this->ColorGreen  = 0;
  this->ColorBlue   = 0;
  this->TotalColors = -1;
  this->ImageFormat = vtkTIFFReader::NOFORMAT;
}

//-------------------------------------------------------------------------
template<typename T>
void vtkTIFFReader::ReadVolume(T* buffer)
{
  int width  = this->InternalImage->Width;
  int height = this->InternalImage->Height;

  for (unsigned int page = 0; page < this->InternalImage->NumberOfPages; ++page)
    {
    this->UpdateProgress(static_cast<double>(page + 1) /
                         this->InternalImage->NumberOfPages);
    if (this->InternalImage->SubFiles > 0)
      {
      long subfiletype = 6;
      if (TIFFGetField(this->InternalImage->Image, TIFFTAG_SUBFILETYPE,
                       &subfiletype))
        {
        if (subfiletype != 0)
          {
          TIFFReadDirectory(this->InternalImage->Image);
          continue;
          }
        }
      }

    // if we have a Zeiss image meaning that the SamplesPerPixel is 2
    if (this->InternalImage->SamplesPerPixel == 2)
      {
      T* volume = buffer;
      volume += width * height * this->InternalImage->SamplesPerPixel * page;
      this->ReadTwoSamplesPerPixelImage(volume, width, height);
      break;
      }
    else if (!this->InternalImage->CanRead())
      {
      uint32 *tempImage = new uint32[width * height];
      if (!TIFFReadRGBAImage(this->InternalImage->Image,
                             width, height,
                             tempImage, 1))
        {
        vtkErrorMacro( << "Cannot read TIFF image or as a TIFF RGBA image" );
        delete [] tempImage;
        return;
        }

      T* fimage = buffer;
      fimage += width * height * 4 * page;
      for (int yy = 0; yy < height; ++yy)
        {
        uint32* ssimage = tempImage + (height - yy - 1) * width;
        for (int xx = 0; xx < width; ++xx)
          {
          *(fimage    ) = static_cast<T>(TIFFGetR(*ssimage)); // Red
          *(fimage + 1) = static_cast<T>(TIFFGetG(*ssimage)); // Green
          *(fimage + 2) = static_cast<T>(TIFFGetB(*ssimage)); // Blue
          *(fimage + 3) = static_cast<T>(TIFFGetA(*ssimage)); // Alpha
          fimage += 4;
          ++ssimage;
          }
        }
      if (tempImage)
        {
        delete [] tempImage;
        tempImage = 0;
        }
      }
    else
      {
      unsigned int format = this->GetFormat();
      switch (format)
        {
        case vtkTIFFReader::GRAYSCALE:
        case vtkTIFFReader::RGB:
        case vtkTIFFReader::PALETTE_RGB:
        case vtkTIFFReader::PALETTE_GRAYSCALE:
          {
          T* volume = buffer;
          volume += width * height * this->InternalImage->SamplesPerPixel * page;
          this->ReadGenericImage(volume, width, height);
          break;
          }
        default:
          return;
        }
      }
    TIFFReadDirectory(this->InternalImage->Image);
    }
}

/** Read a tiled tiff */
void vtkTIFFReader::ReadTiles(void* buffer)
{
  unsigned char* volume = reinterpret_cast<unsigned char*>(buffer);

  for (unsigned int col = 0; col < this->InternalImage->Width;
       col += this->InternalImage->TileWidth)
    {
    for (unsigned int row = 0; row < this->InternalImage->Height;
         row += this->InternalImage->TileHeight)
      {
      unsigned char *tempImage
              = new unsigned char[this->InternalImage->TileWidth *
                                  this->InternalImage->TileHeight *
                                  this->InternalImage->SamplesPerPixel];

      if (TIFFReadTile(this->InternalImage->Image, tempImage, col, row, 0, 0) < 0)
        {
        vtkErrorMacro(<< "Cannot read tile : "<< row << "," << col << " from file");
        delete [] tempImage;
        return;
        }

      for (unsigned int yy = 0; yy < this->InternalImage->TileHeight; ++yy)
        {
        for (unsigned int xx = 0; xx <  this->InternalImage->TileWidth; ++xx)
          {
          for (unsigned int i = 0; i < this->InternalImage->SamplesPerPixel; ++i)
            {
            *volume = *(tempImage++);
            ++volume;
            }
          }
        }
      delete [] tempImage;
      }
    }
}

/** To Support Zeiss images that contains only 2 samples per pixel but are actually
 *  RGB images */
void vtkTIFFReader::ReadTwoSamplesPerPixelImage(void *out,
                                                 unsigned int width,
                                                 unsigned int height)
{
  unsigned int isize = TIFFScanlineSize(this->InternalImage->Image);
  unsigned int cc;
  int row;
  tdata_t buf = _TIFFmalloc(isize);

  int inc = 1;

  if(this->GetDataScalarType() == VTK_UNSIGNED_CHAR)
    {
    unsigned char* image;
     if (this->InternalImage->PlanarConfig == PLANARCONFIG_CONTIG)
      {
      for ( row = 0; row < (int)height; row ++ )
        {
        if (TIFFReadScanline(this->InternalImage->Image, buf, row, 0) <= 0)
          {
          vtkErrorMacro( << "Problem reading the row: " << row );
          break;
          }

        if (this->InternalImage->Orientation == ORIENTATION_TOPLEFT)
          {
          image = reinterpret_cast<unsigned char*>(out) + row * width * inc;
          }
        else
          {
          image = reinterpret_cast<unsigned char*>(out) + width * inc * (height - (row + 1));
          }

        for (cc = 0; cc < isize;
             cc += this->InternalImage->SamplesPerPixel )
          {
          inc = this->EvaluateImageAt( image,
                                       static_cast<unsigned char *>(buf) +
                                       cc );
          image += inc;
          }
        }
      }
    else if(this->InternalImage->PlanarConfig == PLANARCONFIG_SEPARATE)
      {
      unsigned long s;
      unsigned long nsamples = 0;
      TIFFGetField(this->InternalImage->Image, TIFFTAG_SAMPLESPERPIXEL, &nsamples);
      for (s = 0; s < nsamples; s++)
        {
        for ( row = 0; row < (int)height; row ++ )
          {
          if (TIFFReadScanline(this->InternalImage->Image, buf, row, s) <= 0)
            {
            vtkErrorMacro( << "Problem reading the row: " << row );
            break;
            }

          inc = 3;

          if (this->InternalImage->Orientation == ORIENTATION_TOPLEFT)
            {
            image = reinterpret_cast<unsigned char*>(out) + row * width * inc;
            }
          else
            {
            image = reinterpret_cast<unsigned char*>(out) + width * inc * (height - (row + 1));
            }

          // We translate the output pixel to be on the right RGB
          image += s;
          for (cc = 0; cc < isize;
               cc += 1)
            {
            (*image) = *(static_cast<unsigned char *>(buf) + cc);
            inc = 3;
            image += inc;
            }
          }
        }
      }
    }
  else if(this->GetDataScalarType() == VTK_UNSIGNED_SHORT)
    {
    isize /= 2;
    unsigned short* image;
    if (this->InternalImage->PlanarConfig == PLANARCONFIG_CONTIG)
      {
      for ( row = 0; row < (int)height; row ++ )
        {
        if (TIFFReadScanline(this->InternalImage->Image, buf, row, 0) <= 0)
          {
          vtkErrorMacro( << "Problem reading the row: " << row );
          break;
          }

        if (this->InternalImage->Orientation == ORIENTATION_TOPLEFT)
          {
          image = reinterpret_cast<unsigned short*>(out) + row * width * inc;
          }
        else
          {
          image = reinterpret_cast<unsigned short*>(out) + width * inc * (height - (row + 1));
          }

        for (cc = 0; cc < isize;
             cc += this->InternalImage->SamplesPerPixel )
          {
          inc = this->EvaluateImageAt( image,
                                       static_cast<unsigned short *>(buf) +
                                       cc );
          image += inc;
          }
        }
      }
    else if(this->InternalImage->PlanarConfig == PLANARCONFIG_SEPARATE)
      {
      unsigned long s, nsamples;
      TIFFGetField(this->InternalImage->Image, TIFFTAG_SAMPLESPERPIXEL, &nsamples);
      for (s = 0; s < nsamples; s++)
        {
        for ( row = 0; row < (int)height; row ++ )
          {
          if (TIFFReadScanline(this->InternalImage->Image, buf, row, s) <= 0)
            {
            vtkErrorMacro( << "Problem reading the row: " << row );
            break;
            }

          if (this->InternalImage->Orientation == ORIENTATION_TOPLEFT)
            {
            image = reinterpret_cast<unsigned short*>(out) + row * width * inc;
            }
          else
            {
            image = reinterpret_cast<unsigned short*>(out) + width * inc * (height - (row + 1));
            }
          // We translate the output pixel to be on the right RGB
          image += s;
          for (cc = 0; cc < isize;
               cc += 1)
            {
            (*image) = *(static_cast<unsigned short *>(buf) + cc);
            inc = 3;
            image += inc;
            }
          }
        }
      }
    }
  _TIFFfree(buf);
}

template<typename T>
void vtkTIFFReader::ReadGenericImage(T* out, unsigned int, unsigned int height)
{
  unsigned int isize = TIFFScanlineSize(this->InternalImage->Image);
  tdata_t buf = _TIFFmalloc(isize);

  if (this->InternalImage->PlanarConfig != PLANARCONFIG_CONTIG)
    {
    vtkErrorMacro(<< "This reader can only do PLANARCONFIG_CONTIG");
    return;
    }

  T* image;
  if (this->InternalImage->PlanarConfig == PLANARCONFIG_CONTIG)
    {
    int fileRow = 0;
    for (int row = this->OutputExtent[2]; row <= this->OutputExtent[3]; ++row)
      {
      // Flip from lower left origin to upper left if necessary.
      if (this->InternalImage->Orientation == ORIENTATION_TOPLEFT)
        {
        fileRow = row;
        }
      else
        {
        fileRow = height - row - 1;
        }
      if (TIFFReadScanline(this->InternalImage->Image, buf, fileRow, 0) <= 0)
        {
        vtkErrorMacro(<< "Problem reading the row: " << fileRow);
        break;
        }
      image = out + (row - this->OutputExtent[2]) * this->OutputIncrements[1];

      // Copy the pixels into the output buffer
      unsigned int cc = this->OutputExtent[0] * this->InternalImage->SamplesPerPixel;
      for (int ix = this->OutputExtent[0]; ix <= this->OutputExtent[1]; ++ix)
        {
        this->EvaluateImageAt(image, static_cast<T*>(buf) + cc);
        image += this->OutputIncrements[0];
        cc += this->InternalImage->SamplesPerPixel;
        }
      }
    }
  else if(this->InternalImage->PlanarConfig == PLANARCONFIG_SEPARATE)
    {
    int fileRow = 0;
    unsigned long nsamples;
    TIFFGetField(this->InternalImage->Image, TIFFTAG_SAMPLESPERPIXEL, &nsamples);
    for (unsigned long s = 0; s < nsamples; ++s)
      {
      for (int row = this->OutputExtent[2]; row <= this->OutputExtent[3]; ++row)
        {
        if (this->InternalImage->Orientation == ORIENTATION_TOPLEFT)
          {
          fileRow = row;
          }
        else
          {
          fileRow = height - row - 1;
          }
        if (TIFFReadScanline(this->InternalImage->Image, buf, fileRow, s) <= 0)
          {
          vtkErrorMacro( << "Problem reading the row: " << fileRow );
          break;
          }

        image = out + (row-this->OutputExtent[2])*this->OutputIncrements[1];
        unsigned int  cc = this->OutputExtent[0] * this->InternalImage->SamplesPerPixel;
        for (int ix = this->OutputExtent[0]; ix <= this->OutputExtent[1]; ++ix)
          {
          this->EvaluateImageAt(image, static_cast<T*>(buf) + cc);
          image += this->OutputIncrements[0];
          cc += this->InternalImage->SamplesPerPixel;
          }
        }
      }
    }
  _TIFFfree(buf);
}


//-------------------------------------------------------------------------
template<typename T>
void vtkTIFFReader::ReadImageInternal(T* outPtr)
{
  int width  = this->InternalImage->Width;
  int height = this->InternalImage->Height;

  if (!this->InternalImage->CanRead())
    {
    // Why do we read the image for the ! CanRead case?
    uint32 *tempImage = reinterpret_cast<uint32*>(outPtr);

    if (this->OutputExtent[0] != 0 ||
        this->OutputExtent[1] != width - 1 ||
        this->OutputExtent[2] != 0 ||
        this->OutputExtent[3] != height - 1)
      {
      tempImage = new uint32[ width * height ];
      }
    // This should really be fixed to read only the rows necessary.
    if (!TIFFReadRGBAImage(this->InternalImage->Image,
                           width, height,
                           tempImage, 0))
      {
      vtkErrorMacro("Problem reading RGB image");
      if (tempImage != reinterpret_cast<uint32*>(outPtr))
        {
        delete [] tempImage;
        }
      return;
      }
    uint32* ssimage = tempImage;
    T* fimage = outPtr;
    for (int yy = 0; yy < height; ++yy)
      {
      for (int xx = 0; xx < width; ++xx)
        {
        if (xx >= this->OutputExtent[0] &&
            xx <= this->OutputExtent[1] &&
            yy >= this->OutputExtent[2] &&
            yy <= this->OutputExtent[3])
          {
          *(fimage    ) = static_cast<T>(TIFFGetR(*ssimage)); // Red
          *(fimage + 1) = static_cast<T>(TIFFGetG(*ssimage)); // Green
          *(fimage + 2) = static_cast<T>(TIFFGetB(*ssimage)); // Blue
          *(fimage + 3) = static_cast<T>(TIFFGetA(*ssimage)); // Alpha
          fimage += 4;
          }
        ++ssimage;
        }
      }

    if (tempImage != 0 && tempImage != reinterpret_cast<uint32*>(outPtr))
      {
      delete [] tempImage;
      }
    return;
    }

  switch (this->GetFormat())
    {
    case vtkTIFFReader::GRAYSCALE:
    case vtkTIFFReader::RGB:
    case vtkTIFFReader::PALETTE_RGB:
    case vtkTIFFReader::PALETTE_GRAYSCALE:
      this->ReadGenericImage(outPtr, width, height);
      break;
    default:
      return;
    }
}

//-------------------------------------------------------------------------
template<typename T>
int vtkTIFFReader::EvaluateImageAt(T* out, T* in)
{
  unsigned char *image = reinterpret_cast<unsigned char *>(out);
  unsigned char *source =reinterpret_cast<unsigned char *>(in);
  unsigned short red, green, blue;
  switch (this->GetFormat())
    {
    case vtkTIFFReader::GRAYSCALE:
      if (this->InternalImage->Photometrics == PHOTOMETRIC_MINISBLACK)
        {
        *out = *in;
        }
      else
        {
        *image = ~(*source);
        }
      return 1;
    case vtkTIFFReader::PALETTE_GRAYSCALE:
      this->GetColor(*source, &red, &green, &blue);
      *image = static_cast<unsigned char>(red); // red >> 8
      return 1;
    case vtkTIFFReader::RGB:
      *(image    ) = *(source    ); // red
      *(image + 1) = *(source + 1); // green
      *(image + 2) = *(source + 2); // blue
      if (this->InternalImage->SamplesPerPixel == 4)
        {
        *(image + 3) = 255 - *(source + 3); // alpha
        }
      return this->InternalImage->SamplesPerPixel;
    case vtkTIFFReader::PALETTE_RGB:
      this->GetColor(*in, &red, &green, &blue);
      *(out    ) = red << 8;
      *(out + 1) = green << 8;
      *(out + 2) = blue << 8;
      if (this->GetDataScalarType() == VTK_SHORT ||
          this->GetDataScalarType() == VTK_UNSIGNED_SHORT)
        {
        this->GetColor(*in, &red, &green, &blue);
        *(out    ) = red << 8;
        *(out + 1) = green << 8;
        *(out + 2) = blue << 8;
        }
      else
        {
        this->GetColor(*in, &red, &green, &blue);
        *(out    ) = red >> 8;
        *(out + 1) = green >> 8;
        *(out + 2) = blue >> 8;
        }
      return 3;
    default:
      return 0;
    }
}

//-------------------------------------------------------------------------
int vtkTIFFReader::CanReadFile(const char* fname)
{
  vtkTIFFReaderInternal tf;
  int res = tf.Open(fname);
  tf.Clean();
  if (res)
    {
    return 3;
    }
  return 0;
}

//----------------------------------------------------------------------------
void vtkTIFFReader::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os,indent);
  os << indent << "OrientationType: " << this->OrientationType << endl;
  os << indent << "OrientationTypeSpecifiedFlag: " << this->OrientationTypeSpecifiedFlag << endl;
  os << indent << "OriginSpecifiedFlag: " << this->OriginSpecifiedFlag << endl;
  os << indent << "SpacingSpecifiedFlag: " << this->SpacingSpecifiedFlag << endl;
}
