code: private void blur(BufferedImage image) {
  		float[] matrix = GAUSSIAN_BLUR_KERNELS[blurKernelSize - 1];
  		Kernel gaussianBlur1 = new Kernel(matrix.length, 1, matrix);
  		Kernel gaussianBlur2 = new Kernel(1, matrix.length, matrix);
  		RenderingHints hints = new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_SPEED);
  		ConvolveOp gaussianOp1 = new ConvolveOp(gaussianBlur1, ConvolveOp.EDGE_NO_OP, hints);
  		ConvolveOp gaussianOp2 = new ConvolveOp(gaussianBlur2, ConvolveOp.EDGE_NO_OP, hints);
  		BufferedImage scratchImage = EffectUtil.getScratchImage();
  		for (int i = 0; i < blurPasses; i++) {
  			gaussianOp1.filter(image, scratchImage);
  			gaussianOp2.filter(scratchImage, image);
  		}
  	}
docs: Apply blurring to the generate image
  
  @param image The image to be blurred