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Resize images with Java - high quality and working solution

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The following code snippet is copied from http://www.comesolvego.com/2008/04/29/resize-images-with-java-high-quality-and-working-solution/ .

import com.sun.image.codec.jpeg.JPEGImageEncoder;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import javax.swing.*;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.awt.image.Kernel;
import java.awt.image.ConvolveOp;

public class ImageUtil {

    public static void resize(File originalFile, File resizedFile, int newWidth, float quality) throws IOException {

        if (quality < 0 || quality > 1) {
            throw new IllegalArgumentException("Quality has to be between 0 and 1");
        }

        ImageIcon ii = new ImageIcon(originalFile.getCanonicalPath());
        Image i = ii.getImage();
        Image resizedImage = null;

        int iWidth = i.getWidth(null);
        int iHeight = i.getHeight(null);

        if (iWidth > iHeight) {
            resizedImage = i.getScaledInstance(newWidth, (newWidth * iHeight) / iWidth, Image.SCALE_SMOOTH);
        } else {
            resizedImage = i.getScaledInstance((newWidth * iWidth) / iHeight, newWidth, Image.SCALE_SMOOTH);
        }

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

        // Create the buffered image.
        BufferedImage bufferedImage = new BufferedImage(temp.getWidth(null), temp.getHeight(null),
                                                        BufferedImage.TYPE_INT_RGB);

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

        // Clear background and paint the image.
        g.setColor(Color.white);
        g.fillRect(0, 0, temp.getWidth(null), temp.getHeight(null));
        g.drawImage(temp, 0, 0, null);
        g.dispose();

        // Soften.
        float softenFactor = 0.05f;
        float[] softenArray = {0, softenFactor, 0, softenFactor, 1-(softenFactor*4), softenFactor, 0, softenFactor, 0};
        Kernel kernel = new Kernel(3, 3, softenArray);
        ConvolveOp cOp = new ConvolveOp(kernel, ConvolveOp.EDGE_NO_OP, null);
        bufferedImage = cOp.filter(bufferedImage, null);

        // Write the jpeg to a file.
        FileOutputStream out = new FileOutputStream(resizedFile);

        // Encodes image as a JPEG data stream
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);

        JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(bufferedImage);

        param.setQuality(quality, true);

        encoder.setJPEGEncodeParam(param);
        encoder.encode(bufferedImage);

        out.close();
    }

    // Example usage
    public static void main(String[] args) throws IOException {
        File originalImage = new File("/home/username/images/img.jpg");
        resize(originalImage, new File("/home/username/images/img-resized-350-quality-0.7.jpg"), 350, 0.7f);
        resize(originalImage, new File("/home/username/images/img-resized-350-quality-1.jpg"), 350, 1f);
    }

}