The method is to handle the image's width and height. - Java 2D Graphics

Java examples for 2D Graphics:Image

  1. HOME
  2. Java
  3. 2D Graphics
  4. Image

Description

The method is to handle the image's width and height.

Demo Code


//package com.java2s;
import java.awt.Image;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.ImageIO;

public class Main {
    /**/* ww  w  . j a  va 2s.co  m*/
     * The method is to handle the image's width and height. the image is
     * generated according to the new width and new height.
     * 
     * @param imageInputStream
     *            image file inputstream
     * @param nw
     *            the new width
     * @param nh
     *            the new height
     * @return byte[]
     * @throws IOException
     */
    public static byte[] resizeImage(InputStream imageInputStream, int nw,
            int nh) throws IOException {
        AffineTransform transform = new AffineTransform();
        BufferedImage bufferedImage = ImageIO.read(imageInputStream);
        if (bufferedImage == null) {
            return null;
        }
        int w = bufferedImage.getWidth();
        int h = bufferedImage.getHeight();

        double sx = (double) nw / w;
        double sy = (double) nh / h;

        transform.setToScale(sx, sy);

        BufferedImage bid = new BufferedImage(nw, nh,
                BufferedImage.TYPE_INT_ARGB);
        bid.getGraphics().drawImage(
                bufferedImage.getScaledInstance(nw, nh, Image.SCALE_FAST),
                0, 0, null);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        ImageIO.write(bid, "png", baos);
        byte[] imageByte = baos.toByteArray();

        return imageByte;
    }

    public static byte[] resizeImage(byte[] oldImg, int w, int h)
            throws IOException {
        ByteArrayInputStream stream = new ByteArrayInputStream(oldImg);
        byte[] newImg = resizeImage(stream, w, h);
        return newImg;
    }
}

Related Tutorials