java实现图片压缩的思路与代码

本文实例为大家分享了java实现图片压缩的相关代码，供大家参考，具体内容如下

import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
 
import javax.imageio.ImageIO;
 
public class ImageProcess {
 
 private Image img; 
 
 private int width; 
 
 private int height; 
 
 private String imageFormat;
  
 public ImageProcess(InputStream in,String fileName) throws Exception{ 
   //构造Image对象 
   img = ImageIO.read(in); 
   //得到源图宽 
   width = img.getWidth(null);
   //得到源图长 
   height = img.getHeight(null);
   //文件格式
   imageFormat = fileName.substring(fileName.lastIndexOf(".")+1);
 } 
  
 public byte[] resizeFix(int w, int h) throws IOException { 
   if (width / height > w / h) { 
     return resizeByWidth(w); 
   } else { 
     return resizeByHeight(h); 
   } 
 } 
  
 public byte[] resizeByWidth(int w) throws IOException { 
   int h = (int) (height * w / width); 
   return resize(w, h); 
 } 
  
 public byte[] resizeByHeight(int h) throws IOException { 
   int w = (int) (width * h / height); 
   return resize(w, h); 
 } 
  
 public byte[] resize(int w, int h) throws IOException { 
   // SCALE_SMOOTH 的缩略算法 生成缩略图片的平滑度的 优先级比速度高 生成的图片质量比较好 但速度慢 
   BufferedImage image = new BufferedImage(w, h,BufferedImage.TYPE_INT_RGB );  
   image.getGraphics().drawImage(img, 0, 0, w, h, null); // 绘制缩小后的图 
   ByteArrayOutputStream baos = new ByteArrayOutputStream();
   ImageIO.write(image, imageFormat, baos);
   return baos.toByteArray();
 } 
}

以上就是本文的全部内容，希望对大家的学习有所帮助，轻松实现图片压缩操作。