import java.io.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Iterator;
import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageTypeSpecifier;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import javax.imageio.stream.ImageOutputStream;
public class ImageCompression {
public static void main(String[] args) throws IOException {
/*
* if (args.length < 2) { // Exit if both the arguments (Input File and
* Output File) are not provided
* System.err.println("Usage: java TestWriter c:\\in.png c:\\out.png");
* return; }
*/
Iterator writers;
BufferedImage bufferedImage;
ImageOutputStream imageOutputStream;
ImageWriter imageWriter;
ImageWriteParam pngparams;
// Read an image from the disk (First Argument)
// bufferedImage = ImageIO.read(new File(args[0]));
bufferedImage = ImageIO.read(new File("c:\\test.jpg"));
// Get all the PNG writers
writers = ImageIO.getImageWritersByFormatName("jpg");
// Fetch the first writer in the list
imageWriter = (ImageWriter) writers.next();
// Just to confirm that the writer in use is CLibPNGImageWriter
System.out.println("\n Writer used : "
+ imageWriter.getClass().getName() + "\n");
// Specify the parameters according to those the output file will be
// written
// Get Default parameters
pngparams = imageWriter.getDefaultWriteParam();
// Define compression mode
pngparams
.setCompressionMode(javax.imageio.ImageWriteParam.MODE_EXPLICIT);
// Define compression quality
pngparams.setCompressionQuality(0.5F);
// Define progressive mode
pngparams
.setProgressiveMode(javax.imageio.ImageWriteParam.MODE_COPY_FROM_METADATA);
// Deine destination type - used the ColorModel and SampleModel of the
// Input Image
pngparams.setDestinationType(new ImageTypeSpecifier(bufferedImage
.getColorModel(), bufferedImage.getSampleModel()));
// Set the output stream to Second Argument
// imageOutputStream = ImageIO.createImageOutputStream( new
// FileOutputStream(args[1]) );
imageOutputStream = ImageIO
.createImageOutputStream(new FileOutputStream("c:\\new_test.jpg"));
imageWriter.setOutput(imageOutputStream);
// Write the changed Image
imageWriter.write(null, new IIOImage(bufferedImage, null, null),
pngparams);
// Close the streams
imageOutputStream.close();
imageWriter.dispose();
}
}
I picked this code from:
https://coderanch.com/t/430762/Java-General-intermediate/java/Help-java-ImageIO-API-PNG#1926836
