protected int[][] universe;

				public void update() {
    int[][] newUniverse = new int[rowCount][colCount];
    for (int row = 0; row < rowCount; row++) {
        for (int col = 0; col < colCount; col++) {
            newUniverse[row][col] = updateCell(row, col);
        }
    }
    for (int row = 0; row < rowCount; row++) {
        for (int col = 0; col < colCount; col++) {
            universe[row][col] = newUniverse[row][col];
        }
    }
}

protected abstract int updateCell(int row, int col);

				
protected static final int[][] VON_NEUMANN_NEIGHBORHOOD = { { -1, 0 },
        { 1, 0 }, { 0, -1 }, { 0, 1 } };

				
protected int updateCell(int row, int col) {
    int[] neighborStates = getNeighborStates(row, col, neighborhood);
    int currentState = universe[row][col];
    for (int i = 0; i < neighborStates.length; i++) {
        int neighborState = neighborStates[i];
        if (neighborState == (currentState + 1) % n) {
            return neighborState;
        }
    }

    return currentState;
}

BufferedImage filter(BufferedImage src, BufferedImage dest)

				
public BufferedImage filter(BufferedImage src, BufferedImage dest) {
    if (dest == null)
        dest = createCompatibleDestImage(src, null);

    int srcHeight = src.getHeight();
    int srcWidth = src.getWidth();
    for (int y = 0; y < srcHeight; y++) {
        for (int x = 0; x < srcWidth; x++) {
            // Get the pixel in the original image.
            int origRGB = src.getRGB(x, y);
            Color origColor = new Color(origRGB);

            // Get the new RGB values from the filter.
            int[] newRGB = getNewRGB(origColor);

            // Convert the pixel coordinates to the CA coordinates by
            // scaling.
            int cAY = (int) ((double) twoDCellularAutomaton
                    .getRowCount()
                    / (double) srcHeight * y);
            int cAX = (int) ((double) twoDCellularAutomaton
                    .getColCount()
                    / (double) srcWidth * x);
            // Get the state of the corresponding CA cell.
            int state = twoDCellularAutomaton.getState(cAY,
                    cAX);
            // Determine the weight of the filtered RGB values depending on
            // the state.
            double filterProportion = (double) state
                    / (double) twoDCellularAutomaton.getN();

            // Determine the weighted average between the filtered RGB
            // values and the image RGB values.
            int weightedRed = (int) Math.round(newRGB[0] * filterProportion
                    + origColor.getRed() * (1.0 - filterProportion));
            int weightedBlue = (int) Math.round(newRGB[1]
                    * filterProportion + origColor.getBlue()
                    * (1.0 - filterProportion));
            int weightedGreen = (int) Math.round(newRGB[2]
                    * filterProportion + origColor.getGreen()
                    * (1.0 - filterProportion));

            // Set the pixel in dest with this weighted average.
            dest.setRGB(x, y, new Color(weightedRed, weightedBlue,
                    weightedGreen).getRGB());
        }
    }

    return dest;
}

abstract protected int[] getNewRGB(Color color);

				
protected int[] getNewRGB(Color c) {
    int red = c.getRed();
    int newRed = getComplement(red);
    int green = c.getGreen();
    int newGreen = getComplement(green);
    int blue = c.getBlue();
    int newBlue = getComplement(blue);

    return new int[] { newRed, newGreen, newBlue };
}

private int getComplement(int colorVal) {
    // 'Reflect' colorVal across the mid-point 128.
    int maxDiff = colorVal >= 128 ? -colorVal : 255 - colorVal;
    // Divide by 2.0 to make the effect more subtle. Could also just use
    // maxDiff for a more garish effect.
    int diff = (int) Math.round(maxDiff / 2.0);
    int newColorVal = colorVal + diff;

    return newColorVal;
}