Java example source code file (BitDepth.java)

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Java - Java tags/keywords

awt, bitdepth, bufferedimage, byte_binary, byte_gray, color, custom, file, graphics2d, image, imageio, int_bgr, int_rgb, ioexception, runtimeexception, string, test

The BitDepth.java Java example source code

/*
 * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/**
 * @test
 * @bug     4413109 4418221 6607198
 * @run     main BitDepth
 * @summary Checks that the PNG and JPEG writers can handle various
 * BufferedImage types.  An optional list of arguments may be used to
 * test a different format writer or writers.
 */

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;

public class BitDepth {

    public static void main(String[] args) throws IOException {
        new BitDepth(args);
    }

    // Check that the PNG writer can write an all-white image correctly
    private static boolean testPNGByteBinary() throws IOException {
        int width = 10;
        int height = 10;

        File f = new File("BlackStripe.png");
        BufferedImage bi = new BufferedImage(width, height,
                                             BufferedImage.TYPE_BYTE_BINARY);
        Graphics2D g = bi.createGraphics();
        g.setColor(new Color(255, 255, 255));
        g.fillRect(0, 0, width, height);

        ImageIO.write(bi, "png", f);
        BufferedImage bi2 = ImageIO.read(f);
        if (bi2.getWidth() != width || bi2.getHeight() != height) {
            System.out.println("Dimensions changed!");
            return false;
        }

        for (int y = 0; y < height; y++) {
            for (int x = 0; x < width; x++) {
                int rgb = bi2.getRGB(x, y);
                if (rgb != 0xffffffff) {
                    System.out.println("Found a non-white pixel!");
                    return false;
                }
            }
        }

        f.delete();
        return true;
    }

    private static final int[] biRGBTypes = {
        BufferedImage.TYPE_INT_RGB,
        BufferedImage.TYPE_INT_BGR,
        BufferedImage.TYPE_3BYTE_BGR,
        BufferedImage.TYPE_USHORT_565_RGB,
        BufferedImage.TYPE_USHORT_555_RGB
    };

    private static final int[] biRGBATypes = {
        BufferedImage.TYPE_INT_ARGB,
        BufferedImage.TYPE_INT_ARGB_PRE,
        BufferedImage.TYPE_4BYTE_ABGR,
        BufferedImage.TYPE_4BYTE_ABGR_PRE
    };

    private static final int[] biGrayTypes = {
        BufferedImage.TYPE_BYTE_GRAY,
        BufferedImage.TYPE_USHORT_GRAY,
        BufferedImage.TYPE_BYTE_BINARY
    };

    private static final String[] biTypeNames = {
        "CUSTOM",
        "INT_RGB",
        "INT_ARGB",
        "INT_ARGB_PRE",
        "INT_BGR",
        "3BYTE_BGR",
        "4BYTE_ABGR",
        "4BYTE_ABGR_PRE",
        "USHORT_565_RGB",
        "USHORT_555_RGB",
        "BYTE_GRAY",
        "USHORT_GRAY",
        "BYTE_BINARY",
        "BYTE_INDEXED"
    };

    private int width = 80;
    private int height = 80;
    private String[] format = { "png", "jpeg" };

    public BitDepth(String[] args) throws IOException {
        if (args.length > 0) {
            format = args;
        }

        for (int i = 0; i < format.length; i++) {
            testFormat(format[i]);
        }
    }

    private void testFormat(String format) throws IOException {
        boolean allOK = true;

        for (int i = 0; i < biRGBTypes.length; i++) {
            int type = biRGBTypes[i];
            System.out.println("Testing " + format +
                               " writer for type " + biTypeNames[type]);
            File f = testWriteRGB(format, type);
            boolean ok = testReadRGB(f);
            if (ok) {
                f.delete();
            }
            allOK = allOK && ok;
        }

        if (format.equals("png")) {
            System.out.println("Testing png writer for black stripe");
            boolean ok = testPNGByteBinary();
            allOK = allOK && ok;
        }

        if (!allOK) {
            throw new RuntimeException("Test failed");
        }
    }

    private File testWriteRGB(String format, int type)
        throws IOException {
        BufferedImage bi = new BufferedImage(width, height, type);
        Graphics2D g = bi.createGraphics();

        Color white = new Color(255, 255, 255);
        Color red = new Color(255, 0, 0);
        Color green = new Color(0, 255, 0);
        Color blue = new Color(0, 0, 255);

        g.setColor(white);
        g.fillRect(0, 0, width, height);
        g.setColor(red);
        g.fillRect(10, 10, 20, 20);
        g.setColor(green);
        g.fillRect(30, 30, 20, 20);
        g.setColor(blue);
        g.fillRect(50, 50, 20, 20);

        File file = new File("BitDepth_" + biTypeNames[type] + "." + format);
        try {
            ImageIO.write(bi, format, file);
        } catch (RuntimeException re) {
            System.out.println("Can't write a type "
                               + biTypeNames[type] +
                               " BufferedImage!");
        }

        return file;
    }

    private int colorDistance(int color, int r, int g, int b) {
        int r0 = ((color >> 16) & 0xff) - r;
        int g0 = ((color >> 8) & 0xff) - g;
        int b0 = (color & 0xff) - b;
        return r0*r0 + g0*g0 + b0*b0;
    }

    private boolean testReadRGB(File file) throws IOException {
        int[] rgb = new int[3];

        BufferedImage bi = ImageIO.read(file);
        if (bi == null) {
            System.out.println("Couldn't read image!");
            return false;
        }
        int r = bi.getRGB(15, 15);
        if (colorDistance(r, 255, 0, 0) > 20) {
            System.out.println("Red was distorted!");
            return false;
        }
        int g = bi.getRGB(35, 35);
        if (colorDistance(g, 0, 255, 0) > 20) {
            System.out.println("Green was distorted!");
            return false;
        }
        int b = bi.getRGB(55, 55);
        if (colorDistance(b, 0, 0, 255) > 20) {
            System.out.println("Blue was distorted!");
            return false;
        }
        int w = bi.getRGB(55, 15);
        if (colorDistance(w, 255, 255, 255) > 20) {
            System.out.println("White was distorted!");
            return false;
        }

        return true;
    }
}