java中压缩图片的代码辅助类
来源:互联网 发布:linux卸载firefox 编辑:程序博客网 时间:2024/06/05 17:16
- package cn.com.images;
-
- import java.awt.Graphics;
- import java.awt.Image;
- import java.awt.image.BufferedImage;
- import java.io.File;
- import java.io.IOException;
- import java.math.BigDecimal;
- import java.math.MathContext;
- import java.util.ArrayList;
-
- import javax.imageio.ImageIO;
-
-
-
-
-
-
-
-
- public class ImageHelper {
-
- private static ImageHelper imageHelper = null;
-
- public static ImageHelper getImageHelper() {
- if (imageHelper == null) {
- imageHelper = new ImageHelper();
- }
- return imageHelper;
- }
-
-
-
-
-
-
-
-
-
-
-
- public static void scaleImage(String sourceImagePath,
- String destinationPath, double scale,String format) {
-
- File file = new File(sourceImagePath);
- BufferedImage bufferedImage;
- try {
- bufferedImage = ImageIO.read(file);
- int width = bufferedImage.getWidth();
- int height = bufferedImage.getHeight();
-
- width = parseDoubleToInt(width * scale);
- height = parseDoubleToInt(height * scale);
-
- Image image = bufferedImage.getScaledInstance(width, height,
- Image.SCALE_SMOOTH);
- BufferedImage outputImage = new BufferedImage(width, height,
- BufferedImage.TYPE_INT_RGB);
- Graphics graphics = outputImage.getGraphics();
- graphics.drawImage(image, 0, 0, null);
- graphics.dispose();
-
- ImageIO.write(outputImage, format, new File(destinationPath));
- } catch (IOException e) {
- System.out.println("scaleImage方法压缩图片时出错了");
- e.printStackTrace();
- }
-
- }
-
-
-
-
-
-
-
-
-
-
- public static void scaleImageWithParams(String sourceImagePath,
- String destinationPath, int width, int height, boolean auto,String format) {
-
- try {
- File file = new File(sourceImagePath);
- BufferedImage bufferedImage = null;
- bufferedImage = ImageIO.read(file);
- if (auto) {
- ArrayList<Integer> paramsArrayList = getAutoWidthAndHeight(bufferedImage,width,height);
- width = paramsArrayList.get(0);
- height = paramsArrayList.get(1);
- System.out.println("自动调整比例,width="+width+" height="+height);
- }
-
- Image image = bufferedImage.getScaledInstance(width, height,
- Image.SCALE_DEFAULT);
- BufferedImage outputImage = new BufferedImage(width, height,
- BufferedImage.TYPE_INT_RGB);
- Graphics graphics = outputImage.getGraphics();
- graphics.drawImage(image, 0, 0, null);
- graphics.dispose();
- ImageIO.write(outputImage, format, new File(destinationPath));
- } catch (Exception e) {
- System.out.println("scaleImageWithParams方法压缩图片时出错了");
- e.printStackTrace();
- }
-
-
- }
-
-
-
-
-
-
-
- private static int parseDoubleToInt(double sourceDouble) {
- int result = 0;
- result = (int) sourceDouble;
- return result;
- }
-
-
-
-
-
-
-
-
- private static ArrayList<Integer> getAutoWidthAndHeight(BufferedImage bufferedImage,int width_scale,int height_scale){
- ArrayList<Integer> arrayList = new ArrayList<Integer>();
- int width = bufferedImage.getWidth();
- int height = bufferedImage.getHeight();
- double scale_w =getDot2Decimal( width_scale,width);
-
- System.out.println("getAutoWidthAndHeight width="+width + "scale_w="+scale_w);
- double scale_h = getDot2Decimal(height_scale,height);
- if (scale_w<scale_h) {
- arrayList.add(parseDoubleToInt(scale_w*width));
- arrayList.add(parseDoubleToInt(scale_w*height));
- }
- else {
- arrayList.add(parseDoubleToInt(scale_h*width));
- arrayList.add(parseDoubleToInt(scale_h*height));
- }
- return arrayList;
-
- }
-
-
-
-
-
-
-
-
- public static double getDot2Decimal(int a,int b){
-
- BigDecimal bigDecimal_1 = new BigDecimal(a);
- BigDecimal bigDecimal_2 = new BigDecimal(b);
- BigDecimal bigDecimal_result = bigDecimal_1.divide(bigDecimal_2,new MathContext(4));
- Double double1 = new Double(bigDecimal_result.toString());
- System.out.println("相除后的double为:"+double1);
- return double1;
- }
-
- }