Javaで画像からピクセルデータを整数配列として効率的に抽出するにはどうすればよいですか?

int[][] convertTo2DUsingGetRGB(BufferedImage image) {
    int width = image.getWidth();
    int height = image.getHeight();
    int[][] result = new int[height][width];

    for (int row = 0; row < height; row++) {
        for (int col = 0; col < width; col++) {
            result[row][col] = image.getRGB(col, row);
        }
    }

    return result;
}

int[][] convertTo2DWithoutUsingGetRGB(BufferedImage image) {
    final byte[] pixels = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();
    final int width = image.getWidth();
    final int height = image.getHeight();
    final boolean hasAlphaChannel = image.getAlphaRaster() != null;

    int[][] result = new int[height][width];

    // Process pixels with alpha channel
    if (hasAlphaChannel) {
        for (int pixel = 0, row = 0, col = 0; pixel + 3 < pixels.length; pixel += 4) {
            int argb = 0;
            argb += (((int) pixels[pixel] & 0xff) << 24); // alpha
            argb += ((int) pixels[pixel + 1] & 0xff); // blue
            argb += (((int) pixels[pixel + 2] & 0xff) << 8); // green
            argb += (((int) pixels[pixel + 3] & 0xff) << 16); // red
            result[row][col] = argb;
            col++;
            if (col == width) {
                col = 0;
                row++;
            }
        }
    } 
    // Process pixels without alpha channel
    else {
        for (int pixel = 0, row = 0, col = 0; pixel + 2 < pixels.length; pixel += 3) {
            int argb = 0;
            argb += -16777216; // 255 alpha
            argb += ((int) pixels[pixel] & 0xff); // blue
            argb += (((int) pixels[pixel + 1] & 0xff) << 8); // green
            argb += (((int) pixels[pixel + 2] & 0xff) << 16); // red
            result[row][col] = argb;
            col++;
            if (col == width) {
                col = 0;
                row++;
            }
        }
    }

    return result;
}