/* JPEGEncoder.java
Purpose:
Description:
History:
Tue Jun 24 16:16:29 2008, Created by tomyeh
Copyright (C) 2008 Potix Corporation. All Rights Reserved.
{{IS_RIGHT
This program is distributed under LGPL Version 2.1 in the hope that
it will be useful, but WITHOUT ANY WARRANTY.
}}IS_RIGHT
*/
package org.zkoss.image.encoder;
import java.io.ByteArrayOutputStream;
import java.awt.image.RenderedImage;
import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriteParam;
import javax.imageio.ImageWriter;
import javax.imageio.stream.ImageOutputStream;
/**
* The encoder for encoding an image into the JPEG format
*
* @author tomyeh
* @since 3.0.7
*/
public class JPEGEncoder implements ImageEncoder {
private float _quality = 0.95f;
public JPEGEncoder() {
}
public byte[] encode(RenderedImage image) throws java.io.IOException {
ByteArrayOutputStream os = new ByteArrayOutputStream();
ImageWriter iw = ImageIO.getImageWritersByFormatName("jpeg").next();
ImageWriteParam iwp = iw.getDefaultWriteParam();
iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
iwp.setCompressionQuality(_quality);
ImageOutputStream ios = ImageIO.createImageOutputStream(os);
iw.setOutput(ios);
iw.write(null, new IIOImage(image, null, null), iwp);
ios.flush();
iw.dispose();
ios.close();
return os.toByteArray();
}
/** Returns the quality of the image encoding.
* It is a number between 0 and 1. The higher the value,
* the better the output quality.
*
* <p>Default: 0.95f.
*/
public float getQuality() {
return _quality;
}
public void setQuality(float quality) {
if (quality < 0.0f || quality > 1.0f)
throw new IllegalArgumentException("out of range: "+quality);
_quality = quality;
}
public boolean isEncodingAlpha() {
return false;
}
public void setEncodingAlpha(boolean encodeAlpha) {
}
}