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

  Program:   Visualization Toolkit
  Module:    vtkImageDifference.cxx
  Language:  C++
  Date:      $Date$
  Version:   $Revision$

  Copyright (c) 1993-2002 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 "vtkImageDifference.h"

#include "vtkImageData.h"
#include "vtkObjectFactory.h"

vtkCxxRevisionMacro(vtkImageDifference, "1.31");
vtkStandardNewMacro(vtkImageDifference);

// Construct object to extract all of the input data.
vtkImageDifference::vtkImageDifference()
{
  int i;
  for ( i = 0; i < this->NumberOfThreads; i++ )
    {
    this->ErrorPerThread[i] = 0;
    this->ThresholdedErrorPerThread[i] = 0.0;
    }
  this->Threshold = 16;
  this->AllowShift = 1;
  this->Averaging = 1;
}



// not so simple macro for calculating error
#define vtkImageDifferenceComputeError(c1,c2) \
  r1 = abs(((int)(c1)[0] - (int)(c2)[0])); \
  g1 = abs(((int)(c1)[1] - (int)(c2)[1])); \
  b1 = abs(((int)(c1)[2] - (int)(c2)[2]));\
  if ((r1+g1+b1) < (tr+tg+tb)) { tr = r1; tg = g1; tb = b1; } \
  if (this->Averaging && \
      (idx0 > inMinX + 1) && (idx0 < inMaxX - 1) && \
      (idx1 > inMinY + 1) && (idx1 < inMaxY - 1)) \
    {\
  ar1 = (int)(c1)[0]; \
  ag1 = (int)(c1)[1]; \
  ab1 = (int)(c1)[2]; \
  ar2 = (int)(c2)[0] + (int)(c2 - in2Inc0)[0] + (int)(c2 + in2Inc0)[0] + \
        (int)(c2-in2Inc1)[0] + (int)(c2-in2Inc1-in2Inc0)[0] + (int)(c2-in2Inc1+in2Inc0)[0] + \
        (int)(c2+in2Inc1)[0] + (int)(c2+in2Inc1-in2Inc0)[0] + (int)(c2+in2Inc1+in2Inc0)[0]; \
  ag2 = (int)(c2)[1] + (int)(c2 - in2Inc0)[1] + (int)(c2 + in2Inc0)[1] + \
        (int)(c2-in2Inc1)[1] + (int)(c2-in2Inc1-in2Inc0)[1] + (int)(c2-in2Inc1+in2Inc0)[1] + \
        (int)(c2+in2Inc1)[1] + (int)(c2+in2Inc1-in2Inc0)[1] + (int)(c2+in2Inc1+in2Inc0)[1]; \
  ab2 = (int)(c2)[2] + (int)(c2 - in2Inc0)[2] + (int)(c2 + in2Inc0)[2] + \
        (int)(c2-in2Inc1)[2] + (int)(c2-in2Inc1-in2Inc0)[2] + (int)(c2-in2Inc1+in2Inc0)[2] + \
        (int)(c2+in2Inc1)[2] + (int)(c2+in2Inc1-in2Inc0)[2] + (int)(c2+in2Inc1+in2Inc0)[2]; \
  r1 = abs(ar1 - ar2/9); \
  g1 = abs(ag1 - ag2/9); \
  b1 = abs(ab1 - ab2/9); \
  if ((r1+g1+b1) < (tr+tg+tb)) { tr = r1; tg = g1; tb = b1; } \
  ar1 = (int)(c1)[0] + (int)(c1 - in1Inc0)[0] + (int)(c1 + in1Inc0)[0] + \
        (int)(c1-in1Inc1)[0] + (int)(c1-in1Inc1-in1Inc0)[0] + (int)(c1-in1Inc1+in1Inc0)[0] + \
        (int)(c1+in1Inc1)[0] + (int)(c1+in1Inc1-in1Inc0)[0] + (int)(c1+in1Inc1+in1Inc0)[0]; \
  ag1 = (int)(int)(c1)[1] + (int)(c1 - in1Inc0)[1] + (int)(c1 + in1Inc0)[1] + \
        (int)(c1-in1Inc1)[1] + (int)(c1-in1Inc1-in1Inc0)[1] + (int)(c1-in1Inc1+in1Inc0)[1] + \
        (int)(c1+in1Inc1)[1] + (int)(c1+in1Inc1-in1Inc0)[1] + (int)(c1+in1Inc1+in1Inc0)[1]; \
  ab1 = (int)(int)(c1)[2] + (int)(c1 - in1Inc0)[2] + (int)(c1 + in1Inc0)[2] + \
        (int)(c1-in1Inc1)[2] + (int)(c1-in1Inc1-in1Inc0)[2] + (int)(c1-in1Inc1+in1Inc0)[2] + \
        (int)(c1+in1Inc1)[2] + (int)(c1+in1Inc1-in1Inc0)[2] + (int)(c1+in1Inc1+in1Inc0)[2]; \
  r1 = abs(ar1/9 - ar2/9); \
  g1 = abs(ag1/9 - ag2/9); \
  b1 = abs(ab1/9 - ab2/9); \
  if ((r1+g1+b1) < (tr+tg+tb)) { tr = r1; tg = g1; tb = b1; } \
  ar2 = (int)(c2)[0]; \
  ag2 = (int)(c2)[1]; \
  ab2 = (int)(c2)[2]; \
  r1 = abs(ar1/9 - ar2); \
  g1 = abs(ag1/9 - ag2); \
  b1 = abs(ab1/9 - ab2); \
  if ((r1+g1+b1) < (tr+tg+tb)) { tr = r1; tg = g1; tb = b1; } \
    }




//----------------------------------------------------------------------------
// This method computes the input extent necessary to generate the output.
void vtkImageDifference::ComputeInputUpdateExtent(int inExt[6],
                                                          int outExt[6],
                                                          int whichInput)
{
  int *wholeExtent;
  int idx;

  wholeExtent = this->GetInput(whichInput)->GetWholeExtent();
  
  memcpy(inExt,outExt,6*sizeof(int));
  
  // grow input whole extent.
  for (idx = 0; idx < 2; ++idx)
    {
    inExt[idx*2] -= 2;
    inExt[idx*2+1] += 2;

    // we must clip extent with whole extent is we hanlde boundaries.
    if (inExt[idx*2] < wholeExtent[idx*2])
      {
        inExt[idx*2] = wholeExtent[idx*2];
      }
    if (inExt[idx*2 + 1] > wholeExtent[idx*2 + 1])
      {
        inExt[idx*2 + 1] = wholeExtent[idx*2 + 1];
      }
    }
}

//----------------------------------------------------------------------------
void vtkImageDifference::ThreadedExecute(vtkImageData **inData, 
                                         vtkImageData *outData,
                                         int outExt[6], int id)
{
  unsigned char *in1Ptr0, *in1Ptr1, *in1Ptr2;
  unsigned char *in2Ptr0, *in2Ptr1, *in2Ptr2;
  unsigned char *outPtr0, *outPtr1, *outPtr2;
  int min0, max0, min1, max1, min2, max2;
  int idx0, idx1, idx2;
  int in1Inc0, in1Inc1, in1Inc2;
  int in2Inc0, in2Inc1, in2Inc2;
  int outInc0, outInc1, outInc2;
  int tr, tg, tb, r1, g1, b1;
  int ar1, ag1, ab1, ar2, ag2, ab2;
  int inMinX, inMaxX, inMinY, inMaxY;
  int *inExt;
  int matched;
  unsigned long count = 0;
  unsigned long target;
  
  this->ErrorPerThread[id] = 0;
  this->ThresholdedErrorPerThread[id] = 0;
  
  if (inData[0] == NULL || inData[1] == NULL || outData == NULL)
    {
    if (!id)
      {
      vtkErrorMacro(<< "Execute: Missing data");
      }
    this->ErrorPerThread[id] = 1000;
    this->ThresholdedErrorPerThread[id] = 1000;
    return;
    }

  if (inData[0]->GetNumberOfScalarComponents() != 3 ||
      inData[1]->GetNumberOfScalarComponents() != 3 ||
      outData->GetNumberOfScalarComponents() != 3)
    {
    if (!id)
      {
      vtkErrorMacro(<< "Execute: Expecting 3 components (RGB)");
      }
    this->ErrorPerThread[id] = 1000;
    this->ThresholdedErrorPerThread[id] = 1000;
    return;
    }
    
  // this filter expects that input is the same type as output.
  if (inData[0]->GetScalarType() != VTK_UNSIGNED_CHAR || 
      inData[1]->GetScalarType() != VTK_UNSIGNED_CHAR || 
      outData->GetScalarType() != VTK_UNSIGNED_CHAR)
      {
      if (!id)
        {
        vtkErrorMacro(<< "Execute: All ScalarTypes must be unsigned char");
        }
      this->ErrorPerThread[id] = 1000;
      this->ThresholdedErrorPerThread[id] = 1000;
      return;
      }
  
  in1Ptr2 = (unsigned char *) inData[0]->GetScalarPointerForExtent(outExt);  
  in2Ptr2 = (unsigned char *) inData[1]->GetScalarPointerForExtent(outExt);  
  outPtr2 = (unsigned char *) outData->GetScalarPointerForExtent(outExt);  

  inData[0]->GetIncrements(in1Inc0, in1Inc1, in1Inc2);
  inData[1]->GetIncrements(in2Inc0, in2Inc1, in2Inc2);
  outData->GetIncrements(outInc0, outInc1, outInc2);
  
  min0 = outExt[0];  max0 = outExt[1];
  min1 = outExt[2];  max1 = outExt[3];
  min2 = outExt[4];  max2 = outExt[5];
  
  inExt = inData[0]->GetExtent();
  // we set min and Max to be one pixel in from actual values to support 
  // the 3x3 averaging we do
  inMinX = inExt[0]; inMaxX = inExt[1];
  inMinY = inExt[2]; inMaxY = inExt[3];

  target = (unsigned long)((max2 - min2 +1)*(max1 - min1 + 1)/50.0);
  target++;

  for (idx2 = min2; idx2 <= max2; ++idx2)
    {
    in1Ptr1 = in1Ptr2;
    in2Ptr1 = in2Ptr2;
    outPtr1 = outPtr2;
    for (idx1 = min1; !this->AbortExecute && idx1 <= max1; ++idx1)
      {
      if (!id) 
        {
        if (!(count%target))
          {
          this->UpdateProgress(count/(50.0*target));
          }
        count++;
        }
      in1Ptr0 = in1Ptr1;
      in2Ptr0 = in2Ptr1;
      outPtr0 = outPtr1;
      for (idx0 = min0; idx0 <= max0; ++idx0)
        {
        tr = 1000;
        tg = 1000;
        tb = 1000;
      
        /* check the exact match pixel */
        vtkImageDifferenceComputeError(in1Ptr0,in2Ptr0);
        
        // do a quick check to see if this match is exact, if so
        // we can save some seious time by skipping the eight
        // connected neighbors
        matched = 0;
        if ((tr <= 0)&&(tg <= 0)&&(tb <= 0))
          {
          matched = 1;
          }
        
        /* If AllowShift, then we examine neighboring pixels to 
           find the least difference.  This feature is used to 
           allow images to shift slightly between different graphics
           systems, like between opengl and starbase. */
        if (!matched && this->AllowShift) 
          {
          /* lower row */
          if (idx1 > inMinY)
            {
            vtkImageDifferenceComputeError(in1Ptr0-in1Inc1,in2Ptr0);
            if (idx0 > inMinX)
              {
              vtkImageDifferenceComputeError(in1Ptr0-in1Inc0-in1Inc1,in2Ptr0);
              }
            if (idx0 < inMaxX)
              {
              vtkImageDifferenceComputeError(in1Ptr0+in1Inc0-in1Inc1,in2Ptr0);
              }
            }
          /* middle row (center already considered) */
          if (idx0 > inMinX)
            {
            vtkImageDifferenceComputeError(in1Ptr0-in1Inc0,in2Ptr0);
            }
          if (idx0 < inMaxX)
            {
            vtkImageDifferenceComputeError(in1Ptr0+in1Inc0,in2Ptr0);
            }
          /* upper row */
          if (idx1 < inMaxY)
            {
            vtkImageDifferenceComputeError(in1Ptr0+in1Inc1,in2Ptr0);
            if (idx0 > inMinX)
              {
              vtkImageDifferenceComputeError(in1Ptr0-in1Inc0+in1Inc1,in2Ptr0);
              }
            if (idx0 < inMaxX)
              {
              vtkImageDifferenceComputeError(in1Ptr0+in1Inc0+in1Inc1,in2Ptr0);
              }
            }
          }
        
        this->ErrorPerThread[id] = this->ErrorPerThread[id] + (tr + tg + tb)/(3.0*255);
        tr -= this->Threshold;
        if (tr < 0)
          {
          tr = 0;
          }
        tg -= this->Threshold;
        if (tg < 0)
          {
          tg = 0;
          }
        tb -= this->Threshold;
        if (tb < 0)
          {
          tb = 0;
          }
        *outPtr0++ = (unsigned char)tr;
        *outPtr0++ = (unsigned char)tg;
        *outPtr0++ = (unsigned char)tb;
        this->ThresholdedErrorPerThread[id] += (tr + tg + tb)/(3.0*255.0);

        in1Ptr0 += in1Inc0;
        in2Ptr0 += in2Inc0;
        }
      outPtr1 += outInc1;
      in1Ptr1 += in1Inc1;
      in2Ptr1 += in2Inc1;
      }
    outPtr2 += outInc2;
    in1Ptr2 += in1Inc2;
    in2Ptr2 += in2Inc2;
    }
}

//----------------------------------------------------------------------------
// Make sure both the inputs are the same size. Doesn't really change 
// the output. Just performs a sanity check
void vtkImageDifference::ExecuteInformation(vtkImageData **inputs,
                                            vtkImageData *output)
{
  int i;
  int *in1Ext, *in2Ext;
  int ext[6];
  
  // Make sure the Input has been set.
  // we require that input 1 be set.
  if ( ! inputs[0] || ! inputs[1])
    {
    vtkErrorMacro(<< "ExecuteInformation: Input is not set.");
    return;
    }
  
  in1Ext = inputs[0]->GetWholeExtent();
  in2Ext = inputs[1]->GetWholeExtent();

  if (in1Ext[0] != in2Ext[0] || in1Ext[1] != in2Ext[1] || 
      in1Ext[2] != in2Ext[2] || in1Ext[3] != in2Ext[3] || 
      in1Ext[4] != in2Ext[4] || in1Ext[5] != in2Ext[5])
    {
    for (i = 0; i < this->NumberOfThreads; i++)
      {
      this->ErrorPerThread[i] = 1000;
      this->ThresholdedErrorPerThread[i] = 1000;
      }
    vtkErrorMacro("ExecuteInformation: Input are not the same size.");
    }

  // We still need to set the whole extent to be the intersection.
  // Otherwise the execute may crash.
  for (i = 0; i < 3; ++i)
    {
    ext[i*2] = in1Ext[i*2];
    if (ext[i*2] < in2Ext[i*2])
      {
      ext[i*2] = in2Ext[i*2];
      }
    ext[i*2+1] = in1Ext[i*2+1];
    if (ext[i*2+1] > in2Ext[i*2+1])
      {
      ext[i*2+1] = in2Ext[i*2+1];
      }
    }
  output->SetWholeExtent(ext);
}

float vtkImageDifference::GetError()
{
  float error = 0.0;
  int i;

  for ( i= 0; i < this->NumberOfThreads; i++ )
    {
    error += this->ErrorPerThread[i];
    }

  return error;
}

float vtkImageDifference::GetThresholdedError()
{
  float error = 0.0;
  int i;

  for ( i= 0; i < this->NumberOfThreads; i++ )
    {
    error += this->ThresholdedErrorPerThread[i];
    }

  return error;
}

void vtkImageDifference::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os,indent);
  
  int i;

  for ( i= 0; i < this->NumberOfThreads; i++ )
    {
    os << indent << "Error for thread " << i << ": " << this->ErrorPerThread[i] << "\n";
    os << indent << "ThresholdedError for thread " << i << ": " 
       << this->ThresholdedErrorPerThread[i] << "\n";
    }
  os << indent << "Threshold: " << this->Threshold << "\n";
  os << indent << "AllowShift: " << this->AllowShift << "\n";
  os << indent << "Averaging: " << this->Averaging << "\n";
}


