Coding my own filter: pixelation

First we write a specialized image service.

Note that working out of the SDK we can't generalize filters.
Here we process only with a RGB image with UINT8 resolution. We must check that before casting!

bool Pixelate(ImageVariant& ioImage, uint32 iW=4, uint32 iH=4)
{
  if (!ioImage.IsValid() || !ioImage.IsRGBub()) return false;

  const uint32 width = ioImage.GetWidth();
  const uint32 height = ioImage.GetHeight();

  ImageRGBub& specialized = (ImageRGBub&)(*ioImage.GetImpl().get());
  PixelRGBub * prSrc = specialized.GetPixel();

  uint32 x,y,nx,ny;
  for (y=0; y<height; y++)
    for (x=0; x<width; x++)
  {
    nx = Math::elxFloor(x / iW) * iW;
    ny = Math::elxFloor(y / iH) * iH;
    *prSrc++ = *specialized.GetPixel(nx,ny);
  }
}

Now let's test it:

cout << "Coding my own filter" << endl;

ImageVariant image("../../datas/planet.jpg");
bool bSuccess = Pixelate(image, 6,6);
image.Save("output/planet-pixelized.jpg");

planet.jpg

planet-pixelized.jpg