code: private static void normalize2D(GrayU8 gray) {
  		// Create a Gaussian kernel with radius of 3
  		Kernel2D_S32 kernel = FactoryKernelGaussian.gaussian2D(GrayU8.class, -1, 3);
  		// Note that there is a more efficient way to compute this convolution since it is a separable kernel
  		// just use BlurImageOps instead.
  
  		// Since it's normalized it can be saved inside an 8bit image
  		GrayU8 output = new GrayU8(gray.width,gray.height);
  
  		GConvolveImageOps.convolveNormalized(kernel, gray, output);
  		panel.addImage(VisualizeImageData.standard(output, null), "2D Normalized Kernel");
  	}
docs: Convolves a 2D normalized kernel.  This kernel is divided by its sum after computation.