@Override
	protected ArrayList<ColorPatch> doInBackground() throws Exception {
		ArrayList<ColorPatch> patches = new ArrayList<>();
		
		publish(new Double(0.0));
		
		for (int y=0; y<image.getHeight(); ++y) {
			for (int x=0; x<image.getWidth(); ++x) {
				if ( isIncluded(x, y) ) {
					ColorPatch patch = followPixel(x, y);
					if ( patch != null ) {
						patches.add(patch);
						System.out.println("Got patch: "+patch);
					}
				}
			}
			publish(new Double((double)(y+1)/image.getHeight()));
		}
		
		return patches;
	}