java高质量缩放图片的示例代码_Java教程

java高质量缩放图片的示例代码

2020-09-12 00:44TianZe Java教程

这篇文章主要介绍了java高质量缩放图片的示例代码，帮助大家更好的使用Java处理图片，感兴趣的朋友可以了解下

可按照比例缩放，也可以指定宽高

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									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 {

									   /**

									   * 

									   * @param originalFile 原文件

									   * @param resizedFile 压缩目标文件

									   * @param newWidth 压缩后的图片宽度

									   * @param quality 压缩质量（0到1之间，越高质量越好）

									   * @throws IOException

									   */

									    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);

									        //比例缩放

									        if (iWidth > iHeight) {

									            resizedImage = i.getScaledInstance(newWidth, (newWidth * iHeight)

									                    / iWidth, Image.SCALE_SMOOTH);

									        } else {

									            resizedImage = i.getScaledInstance((newWidth * iWidth) / iHeight,

									                    newWidth, Image.SCALE_SMOOTH);

									        }

									        //指定宽高

									        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:P7.gif");

									         resize(originalImage, new File("c:P7-0.jpg"),150, 0.7f);

									         resize(originalImage, new File("c:P7-1.jpg"),150, 1f);

									    }

									}