FasTC/Base/src/Image.cpp

/* FasTC
 * Copyright (c) 2012 University of North Carolina at Chapel Hill. All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its documentation for educational, 
 * research, and non-profit purposes, without fee, and without a written agreement is hereby granted, 
 * provided that the above copyright notice, this paragraph, and the following four paragraphs appear 
 * in all copies.
 *
 * Permission to incorporate this software into commercial products may be obtained by contacting the 
 * authors or the Office of Technology Development at the University of North Carolina at Chapel Hill <otd@unc.edu>.
 *
 * This software program and documentation are copyrighted by the University of North Carolina at Chapel Hill. 
 * The software program and documentation are supplied "as is," without any accompanying services from the 
 * University of North Carolina at Chapel Hill or the authors. The University of North Carolina at Chapel Hill 
 * and the authors do not warrant that the operation of the program will be uninterrupted or error-free. The 
 * end-user understands that the program was developed for research purposes and is advised not to rely 
 * exclusively on the program for any reason.
 *
 * IN NO EVENT SHALL THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL OR THE AUTHORS BE LIABLE TO ANY PARTY FOR 
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE 
 * USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL OR THE 
 * AUTHORS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL AND THE AUTHORS SPECIFICALLY DISCLAIM ANY WARRANTIES, INCLUDING, 
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE AND ANY 
 * STATUTORY WARRANTY OF NON-INFRINGEMENT. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY 
 * OF NORTH CAROLINA AT CHAPEL HILL AND THE AUTHORS HAVE NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, 
 * ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Please send all BUG REPORTS to <pavel@cs.unc.edu>.
 *
 * The authors may be contacted via:
 *
 * Pavel Krajcevski
 * Dept of Computer Science
 * 201 S Columbia St
 * Frederick P. Brooks, Jr. Computer Science Bldg
 * Chapel Hill, NC 27599-3175
 * USA
 * 
 * <http://gamma.cs.unc.edu/FasTC/>
 */

#include "Image.h"

#include <algorithm>
#include <cstdlib>
#include <cstdio>
#include <cstring>
#include <cassert>
#include <cmath>

#include "Color.h"
#include "Pixel.h"
#include "IPixel.h"

template <typename T>
static inline T sad( const T &a, const T &b ) {
  return (a > b)? a - b : b - a;
}

namespace FasTC {

template<typename PixelType>
Image<PixelType>::Image(uint32 width, uint32 height)
  : m_Width(width)
  , m_Height(height)
  , m_bBlockStreamOrder(false)
  , m_Pixels(new PixelType[GetNumPixels()])
{ }

template<typename PixelType>
Image<PixelType>::Image(uint32 width, uint32 height,
                        const PixelType *pixels,
                        bool bBlockStreamOrder)
  : m_Width(width)
  , m_Height(height)
  , m_bBlockStreamOrder(false)
{
  if(pixels) {
    m_Pixels = new PixelType[GetNumPixels()];
    memcpy(m_Pixels, pixels, GetNumPixels() * sizeof(PixelType));
  } else {
    m_Pixels = 0;
  }
}

template<typename PixelType>
Image<PixelType>::Image(const Image<PixelType> &other)
  : m_Width(other.m_Width)
  , m_Height(other.m_Height)
  , m_bBlockStreamOrder(other.GetBlockStreamOrder())
  , m_Pixels(new PixelType[GetNumPixels()])
{
  memcpy(m_Pixels, other.m_Pixels, GetNumPixels() * sizeof(PixelType));
}

template<typename PixelType>
bool Image<PixelType>::ReadPixels(const uint32 *rgba) {

  assert(m_Pixels);
  for(uint32 i = 0; i < GetNumPixels(); i++) {
    m_Pixels[i].Unpack(rgba[i]);
  }

  return true;
}

template<typename PixelType>
Image<PixelType>::Image(uint32 width, uint32 height, const uint32 *pixels, bool bBlockStreamOrder)
  : m_Width(width)
  , m_Height(height)
  , m_bBlockStreamOrder(bBlockStreamOrder)
{
  if(pixels) {
    m_Pixels = new PixelType[GetNumPixels()];
    ReadPixels(pixels);
  } else {
    m_Pixels = NULL;
  }
}

template<typename PixelType>
Image<PixelType>::~Image() {
  if(m_Pixels) {
    delete [] m_Pixels;
    m_Pixels = 0;
  }
}

template<typename PixelType>
Image<PixelType> &Image<PixelType>::operator=(const Image &other) {
  
  m_Width = other.m_Width;
  m_Height = other.m_Height;
  m_bBlockStreamOrder = other.GetBlockStreamOrder();
  
  if(m_Pixels) {
    delete [] m_Pixels;
  }
  
  if(other.m_Pixels) {
    m_Pixels = new PixelType[GetNumPixels()];
    if(m_Pixels)
      memcpy(m_Pixels, other.m_Pixels, GetNumPixels() * sizeof(PixelType));
    else
      fprintf(stderr, "Out of memory!\n");
  } else {
    m_Pixels = NULL;
  }

  return *this;
}

template<typename PixelType>
PixelType & Image<PixelType>::operator()(uint32 i, uint32 j) {
  assert(i < GetWidth());
  assert(j < GetHeight());
  return m_Pixels[j * GetWidth() + i];
}

template<typename PixelType>
const PixelType & Image<PixelType>::operator()(uint32 i, uint32 j) const {
  assert(i < GetWidth());
  assert(j < GetHeight());
  return m_Pixels[j * GetWidth() + i];
}

template<typename PixelType>
double Image<PixelType>::ComputePSNR(Image<PixelType> *other) {
  if(!other)
    return -1.0;

  if(GetWidth() != other->GetWidth() ||
     GetHeight() != other->GetHeight()) {
    return -1.0;
  }

  // Compute raw 8-bit RGBA data...
  ComputePixels();
  other->ComputePixels();

  const PixelType *ourPixels = GetPixels();
  const PixelType *otherPixels = other->GetPixels();

  //  const double w[3] = { 0.2126, 0.7152, 0.0722 };
  const double w[3] = { 1.0, 1.0, 1.0 };
    
  double mse = 0.0;
  const uint32 imageSz = GetNumPixels();
  for(uint32 i = 0; i < imageSz; i++) {

    uint32 ourPixel = ourPixels[i].Pack();
    uint32 otherPixel = otherPixels[i].Pack();

    double r[4], u[4];
    for(uint32 c = 0; c < 4; c++) {
      uint32 shift = c * 8;
      if(c == 3) {
        r[c] = static_cast<double>((ourPixel >> shift) & 0xFF) / 255.0;
        u[c] = static_cast<double>((otherPixel >> shift) & 0xFF) / 255.0;
      } else {
        r[c] = static_cast<double>((ourPixel >> shift) & 0xFF) * w[c];
        u[c] = static_cast<double>((otherPixel >> shift) & 0xFF) * w[c];
      }
    }

    for(uint32 c = 0; c < 3; c++) {
      double diff = (r[3] * r[c] - u[3] * u[c]);
      mse += diff * diff;
    }
  }

  mse /= GetWidth() * GetHeight();

  const double C = 255.0 * 255.0;
  double maxi = (w[0]*w[0] + w[1]*w[1] + w[2]*w[2]) * C;
  return 10 * log10(maxi/mse);
}

// !FIXME! These won't work for non-RGBA8 data.
template<typename PixelType>
void Image<PixelType>::ConvertToBlockStreamOrder() {
  if(m_bBlockStreamOrder || !m_Pixels)
    return;

  PixelType *newPixelData = new PixelType[GetWidth() * GetHeight()];
  for(uint32 j = 0; j < GetHeight(); j+=4) {
    for(uint32 i = 0; i < GetWidth(); i+=4) {
      uint32 blockX = i / 4;
      uint32 blockY = j / 4;
      uint32 blockIdx = blockY * (GetWidth() / 4) + blockX;

      uint32 offset = blockIdx * 4 * 4;
      for(uint32 t = 0; t < 16; t++) {
        uint32 x = i + t % 4;
        uint32 y = j + t / 4;
        newPixelData[offset + t] = m_Pixels[y*GetWidth() + x];
      }
    }
  }

  delete m_Pixels;
  m_Pixels = newPixelData;
  m_bBlockStreamOrder = true;
}

template<typename PixelType>
void Image<PixelType>::ConvertFromBlockStreamOrder() {
  if(!m_bBlockStreamOrder || !m_Pixels)
    return;

  PixelType *newPixelData = new PixelType[GetWidth() * GetHeight()];
  for(uint32 j = 0; j < GetHeight(); j+=4) {
    for(uint32 i = 0; i < GetWidth(); i+=4) {
      uint32 blockX = i / 4;
      uint32 blockY = j / 4;
      uint32 blockIdx = blockY * (GetWidth() / 4) + blockX;

      uint32 offset = blockIdx * 4 * 4;
      for(uint32 t = 0; t < 16; t++) {
        uint32 x = i + t % 4;
        uint32 y = j + t / 4;
        newPixelData[y*GetWidth() + x] = m_Pixels[offset + t];
      }
    }
  }

  delete m_Pixels;
  m_Pixels = newPixelData;
  m_bBlockStreamOrder = false;
}

template<typename PixelType>
void Image<PixelType>::SetImageData(uint32 width, uint32 height, PixelType *data) {
  if(m_Pixels) {
    delete m_Pixels;
  }

  if(!data) {
    width = 0;
    height = 0;
    m_Pixels = NULL;
  } else {
    m_Width = width;
    m_Height = height;
    m_Pixels = data;
  }
}

  template<typename T>
  static inline T Clamp(const T &v, const T &a, const T &b) {
    return ::std::min(::std::max(a, v), b);
  }

template<typename PixelType>
void Image<PixelType>::Filter(const Image<IPixel> &kernel) {
  Image<IPixel> k(kernel);

  // Only odd sized filters make sense....
  assert(k.GetWidth() % 2);
  assert(k.GetHeight() % 2);

  double sum = 0.0;
  for(uint32 j = 0; j < k.GetHeight(); j++) {
    for(uint32 i = 0; i < k.GetWidth(); i++) {
      sum += static_cast<float>(k(i, j));
    }
  }

  for(uint32 j = 0; j < k.GetHeight(); j++) {
    for(uint32 i = 0; i < k.GetWidth(); i++) {
      k(i, j) = static_cast<float>(k(i, j)) / sum;
    }
  }

  int32 ih = static_cast<int32>(GetHeight());
  int32 iw = static_cast<int32>(GetWidth());

  int32 kh = static_cast<int32>(k.GetHeight());
  int32 kw = static_cast<int32>(k.GetWidth());

  Image<PixelType> filtered(iw, ih);

  for(int32 j = 0; j < ih; j++) {
    for(int32 i = 0; i < iw; i++) {
      int32 yoffset = j - (k.GetHeight() / 2);
      int32 xoffset = i - (k.GetWidth() / 2);

      Color newPixel;
      for(int32 y = 0; y < kh; y++) {
        for(int32 x = 0; x < kw; x++) {
          PixelType pixel = ((*this)(
            Clamp<int32>(x + xoffset, 0, GetWidth() - 1),
            Clamp<int32>(y + yoffset, 0, GetHeight() - 1)));
          Color c; c.Unpack(pixel.Pack());
          Color scaled = c * static_cast<float>(k(x, y));
          newPixel += scaled;
        }
      }

      filtered(i, j).Unpack(newPixel.Pack());
    }
  }

  *this = filtered;
}

template class Image<Pixel>;
template class Image<IPixel>;
template class Image<Color>;

void GenerateGaussianKernel(Image<IPixel> &out, uint32 size, float sigma) {

  assert(size % 2);

  out = Image<IPixel>(size, size);
  if(size == 1) {
    out(0, 0) = 1.0f;
    return;
  }

  int32 halfSz = static_cast<int32>(size) / 2;
  for(int32 j = -halfSz; j < halfSz; j++) {
    for(int32 i = -halfSz; i < halfSz; i++) {
      out(halfSz + i, halfSz + j) = exp(- (j*j + i*i) / (2*sigma*sigma));
    }
  }
}

}  // namespace FasTC