public static void main(String[] args) {
if (args.length < 1) {
System.out.printf("Usage: ImageProcessor205BW <input image>\n");
return;
}
String input_filename = args[0];
if (!input_filename.toLowerCase().endsWith(".png"))
ErrorExit("Input file must be a PNG image.\n");
String output_filename = null;
if (args.length > 1) output_filename = args[1];
else output_filename = input_filename.substring(0, input_filename.length() - 4) + "_output.png";
Color[][] inputPixels = load_image(input_filename);
int[][] inputIntensities = ColoursToIntensities(inputPixels);
int[][] resultIntensities = ProcessImage(inputIntensities);
Color[][] resultPixels = IntensitiesToColours(resultIntensities);
save_image(resultPixels, output_filename);
}
private static void save_image(Color[][] imagePixels, String image_filename) {
int width = imagePixels.length;
int height = imagePixels[0].length;
BufferedImage outputImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
for (int x = 0; x < width; x++)
for (int y = 0; y < height; y++) outputImage.setRGB(x, y, imagePixels[x][y].getRGB());
try {
ImageIO.write(outputImage, "png", new File(image_filename));
} catch (java.io.IOException e) {
ErrorExit("Unable to write %s: %s\n", image_filename, e.getMessage());
}
System.err.printf("Wrote a %d by %d image\n", width, height);
}
private static Color[][] load_image(String image_filename) {
BufferedImage inputImage = null;
try {
System.err.printf("Reading image from %s\n", image_filename);
inputImage = ImageIO.read(new File(image_filename));
} catch (java.io.IOException e) {
ErrorExit("Unable to open %s: %s\n", image_filename, e.getMessage());
}
int width = inputImage.getWidth();
int height = inputImage.getHeight();
Color[][] imagePixels = new Color[width][height];
for (int x = 0; x < width; x++)
for (int y = 0; y < height; y++) imagePixels[x][y] = new Color(inputImage.getRGB(x, y));
System.err.printf("Read a %d by %d image\n", width, height);
return imagePixels;
}