本文实例讲述了Java实现的图片高质量缩放类定义与用法。分享给大家供大家参考，具体如下：
找了很多都不理想，最后找个到老外写的，不得不承认老外写的确实牛B。
package com.test;
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 > 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);
} // Example usage
public static void main(String[] args) throws IOException {
// File originalImage = new File("C:\\11.jpg");
// resize(originalImage, new File("c:\\11-0.jpg"),150, 0.7f);
// resize(originalImage, new File("c:\\11-1.jpg"),150, 1f);
File originalImage = new File("C:\\1207.gif");
resize(originalImage, new File("c:\\1207-0.jpg"),150, 0.7f);
resize(originalImage, new File("c:\\1207-1.jpg"),150, 1f);
}
}
更多java相关内容感兴趣的读者可查看本站专题：《Java图片操作技巧汇总》、《java日期与时间操作技巧汇总》、《Java操作DOM节点技巧总结》、《Java文件与目录操作技巧汇总》及《Java数据结构与算法教程》。
希望本文所述对大家java程序设计有所帮助。
