Esempio n. 1
0
void R2Image::
Multiply(const R2Image& image) 
{
  // Multiply by image pixel-by-pixel
  assert(image.Width() == Width());
  assert(image.Height() == Height());
  assert(image.NChannels() == NChannels());
  int nvalues = NValues();
  for (int i = 0; i < nvalues; i++) {
    pixels[i] *= image.pixels[i];
  }
}
Esempio n. 2
0
void R2Image::
Subtract(const R2Image& image) 
{
  // Subtract image pixel-by-pixel
  assert(image.Width() == Width());
  assert(image.Height() == Height());
  assert(image.NChannels() == NChannels());
  int nvalues = NValues();
  for (int i = 0; i < nvalues; i++) {
    pixels[i] -= image.pixels[i];
  }
}
Esempio n. 3
0
void R2Image::
Divide(const R2Image& image) 
{
  // Add image pixel-by-pixel
  assert(image.Width() == Width());
  assert(image.Height() == Height());
  assert(image.NChannels() == NChannels());
  int nvalues = NValues();
  for (int i = 0; i < nvalues; i++) {
    if (image.pixels[i] == 0) {
      if (pixels[i] == 0.0) continue;
      else pixels[i] = FLT_MAX;
    }
    else {
      pixels[i] /= image.pixels[i];
    }
  }
}
Esempio n. 4
0
void R2Image::
Filter(const R2Image& filter) 
{
  // Get useful variables
  int xr = filter.Width()/2;
  int yr = filter.Height()/2;
  R2Image copy(*this);

  // This is the straight-forward implementation (slow for large filters)
  for (int j = 0; j < Height(); j++) {
    for (int i = 0; i < Width(); i++) {
      for (int c = 0; c < NChannels(); c++) {
        int fc = (NChannels() == filter.NChannels()) ? c : 0;

        // Compute new value 
        double sum = 0;
        for (int s = 0; s < filter.Width(); s++) {
          int x = i - xr + s;
          if (x < 0) x = 0;
          else if (x >= Width()) x = Width()-1;
          for (int t = 0; t < filter.Height(); t++) {
            int y = j - yr + t;
            if (y < 0) y = 0;
            else if (y >= Height()) y = Height()-1;
            double filter_value = filter.Value(s, t, fc);
            double image_value = copy.Value(x, y, c);
            sum += filter_value * image_value;
          }
        }

        // Assign new value for channel
        SetValue(i, j, c, sum);
      }
    }
  }
}