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。