Image Rotate in Java #2 : easier to use

I’ve combine the source I provided in the first article , which receive and return BufferedImage object , with the Image to a BufferedImage code that I’ve found from http://www.exampledepot.com/egs/java.awt.image/Image2Buf.html.

The result is the Class ImageUtils with the rotateImage() method that receive 2 parameters , img – an Image object to rotate and degree – the integer value of the degree that img will be rotated, the code is all shown below :).

** please note that I’m ONLY just combine these code to make it easier to use and I DIDN’T wrote it all myself.

// ImageUtils.java

package mystic.utils;

import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.HeadlessException;
import java.awt.Image;
import java.awt.Transparency;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.PixelGrabber;
import javax.swing.ImageIcon;

public class ImageUtils {

    public static Image rotateImage(Image img,double degree){
        BufferedImage bufImg = toBufferedImage(img);
        double angle = Math.toRadians(degree);

        return tilt(bufImg,angle);
    }

    public static BufferedImage tilt(BufferedImage image, double angle) {
        double sin = Math.abs(Math.sin(angle)), cos = Math.abs(Math.cos(angle));
        int w = image.getWidth(), h = image.getHeight();
        int neww = (int)Math.floor(w*cos+h*sin), newh = (int)Math.floor(h*cos+w*sin);
        GraphicsConfiguration gc = getDefaultConfiguration();
        BufferedImage result = gc.createCompatibleImage(neww, newh, Transparency.TRANSLUCENT);
        Graphics2D g = result.createGraphics();
        g.translate((neww-w)/2, (newh-h)/2);
        g.rotate(angle, w/2, h/2);
        g.drawRenderedImage(image, null);
        g.dispose();
        return result;
    }

    public static GraphicsConfiguration getDefaultConfiguration() {
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        GraphicsDevice gd = ge.getDefaultScreenDevice();
        return gd.getDefaultConfiguration();
    }

    // http://www.exampledepot.com/egs/java.awt.image/Image2Buf.html
    // An Image object cannot be converted to a BufferedImage object.
    // The closest equivalent is to create a buffered image and then draw the image on the buffered image.
    // This example defines a method that does this.

    // This method returns a buffered image with the contents of an image
    public static BufferedImage toBufferedImage(Image image) {
        if (image instanceof BufferedImage) {
            return (BufferedImage)image;
        }

        // This code ensures that all the pixels in the image are loaded
        image = new ImageIcon(image).getImage();

        // Determine if the image has transparent pixels; for this method's
        // implementation, see e661 Determining If an Image Has Transparent Pixels
        boolean hasAlpha = hasAlpha(image);

        // Create a buffered image with a format that's compatible with the screen
        BufferedImage bimage = null;
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        try {
            // Determine the type of transparency of the new buffered image
            int transparency = Transparency.OPAQUE;
            if (hasAlpha) {
                transparency = Transparency.BITMASK;
            }

            // Create the buffered image
            GraphicsDevice gs = ge.getDefaultScreenDevice();
            GraphicsConfiguration gc = gs.getDefaultConfiguration();
            bimage = gc.createCompatibleImage(
                image.getWidth(null), image.getHeight(null), transparency);
        } catch (HeadlessException e) {
            // The system does not have a screen
        }

        if (bimage == null) {
            // Create a buffered image using the default color model
            int type = BufferedImage.TYPE_INT_RGB;
            if (hasAlpha) {
                type = BufferedImage.TYPE_INT_ARGB;
            }
            bimage = new BufferedImage(image.getWidth(null), image.getHeight(null), type);
        }

        // Copy image to buffered image
        Graphics g = bimage.createGraphics();

        // Paint the image onto the buffered image
        g.drawImage(image, 0, 0, null);
        g.dispose();

        return bimage;
    }

    // http://www.exampledepot.com/egs/java.awt.image/HasAlpha.html
    // This method returns true if the specified image has transparent pixels
    public static boolean hasAlpha(Image image) {
        // If buffered image, the color model is readily available
        if (image instanceof BufferedImage) {
            BufferedImage bimage = (BufferedImage)image;
            return bimage.getColorModel().hasAlpha();
        }

        // Use a pixel grabber to retrieve the image's color model;
        // grabbing a single pixel is usually sufficient
         PixelGrabber pg = new PixelGrabber(image, 0, 0, 1, 1, false);
        try {
            pg.grabPixels();
        } catch (InterruptedException e) {
        }

        // Get the image's color model
        ColorModel cm = pg.getColorModel();
        return cm.hasAlpha();
    }
}

Image Rotate in Java

Source : http://forum.java.sun.com/thread.jspa?threadID=487900&messageID=2286191

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;
import java.net.*;
import javax.imageio.*;
import javax.swing.*;

public class Tilt {
    public static void main(String[] args) throws IOException {
        URL url = new URL("http://weblogs.java.net/jag/Image1-large.jpeg");
        final BufferedImage image = ImageIO.read(url);
        final JLabel label = new JLabel(new ImageIcon(image));
        new Timer(100, new ActionListener(){
            double angle = 0;
            public void actionPerformed(ActionEvent evt) {
                angle += Math.PI/50;
                label.setIcon(new ImageIcon(tilt(image, angle)));
            }
        }).start();
        JFrame f = new JFrame("TILT");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(label);
        f.setSize(400,400);
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    public static BufferedImage tilt(BufferedImage image, double angle) {
        double sin = Math.abs(Math.sin(angle)), cos = Math.abs(Math.cos(angle));
        int w = image.getWidth(), h = image.getHeight();
        int neww = (int)Math.floor(w*cos+h*sin), newh = (int)Math.floor(h*cos+w*sin);
        GraphicsConfiguration gc = getDefaultConfiguration();
        BufferedImage result = gc.createCompatibleImage(neww, newh, Transparency.TRANSLUCENT);
        Graphics2D g = result.createGraphics();
        g.translate((neww-w)/2, (newh-h)/2);
        g.rotate(angle, w/2, h/2);
        g.drawRenderedImage(image, null);
        g.dispose();
        return result;
    }

    public static GraphicsConfiguration getDefaultConfiguration() {
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        GraphicsDevice gd = ge.getDefaultScreenDevice();
        return gd.getDefaultConfiguration();
    }
}

you can also try a getRotateInstance (double, int, int) too. (from comment in that thread)