图片压缩java

缺乏、安全感 2023-10-03 17:54 45阅读 0赞

[java 实现图片压缩 - \_\_\_mouM - 博客园][java _ - _mouM -]

转载https://www.cnblogs.com/strongmore/p/14158639.html

添加依赖

<dependency>
      <groupId>net.coobird</groupId>
      <artifactId>thumbnailator</artifactId>
      <version>0.4.8</version>
    </dependency>

按质量压缩

import java.io.File;
    import java.io.FileOutputStream;
    import net.coobird.thumbnailator.Thumbnails;
    
    public class Client {
    
      public static void main(String[] args) throws Exception {
        Thumbnails.of(new File("D:/showqrcode.jpg"))
            .scale(1f) //图片大小（长宽）压缩比例 从0-1，1表示原图
            .outputQuality(0.5f) //图片质量压缩比例 从0-1，越接近1质量越好
            .toOutputStream(new FileOutputStream("D:/showqrcode_50.jpg"));
      }
    
    }
    按比例缩放
    
    import java.io.File;
    import java.io.FileOutputStream;
    import net.coobird.thumbnailator.Thumbnails;
    
    public class Client2 {
    
      public static void main(String[] args) throws Exception {
        Thumbnails.of(new File("D:/showqrcode.jpg"))
            .scale(0.5f) //图片大小（长宽）压缩 从0按照
            .outputQuality(0.5f) //图片质量压缩比例 从0-1，越接近1质量越好
            .toOutputStream(new FileOutputStream("D:/showqrcode_50%.jpg"));
      }
    
    }

按大小和比例缩放

import java.io.File;
    import java.io.FileOutputStream;
    import net.coobird.thumbnailator.Thumbnails;
    
    public class Client21 {
    
      public static void main(String[] args) throws Exception {
        Thumbnails.of(new File("D:/showqrcode.jpg"))
            .size(500, 300) // 图片比例不变
            .toOutputStream(new FileOutputStream("D:/showqrcode_500_300.jpg"));
      }
    
    }
    按大小缩放
    
    import java.io.File;
    import java.io.FileOutputStream;
    import net.coobird.thumbnailator.Thumbnails;
    
    public class Client22 {
    
      public static void main(String[] args) throws Exception {
        Thumbnails.of(new File("D:/showqrcode.jpg"))
            .forceSize(500, 300) //不保持图片比例
            .toOutputStream(new FileOutputStream("D:/showqrcode_500_300.jpg"));
      }
    
    }
    旋转 
    import java.io.File;
    import java.io.FileOutputStream;
    import net.coobird.thumbnailator.Thumbnails;
    
    public class Client3 {
    
      public static void main(String[] args) throws Exception {
        Thumbnails.of(new File("D:/showqrcode.jpg"))
            .forceSize(500, 300)
            .rotate(90f) //向右旋转
            .toOutputStream(new FileOutputStream("D:/showqrcode+90.jpg"));
      }
    
    }
    加水印
    import java.io.File;
    import java.io.IOException;
    import javax.imageio.ImageIO;
    import net.coobird.thumbnailator.Thumbnails;
    import net.coobird.thumbnailator.geometry.Positions;
    
    public class Client4 {
    
      public static void main(String[] args) throws IOException {
        Thumbnails.of("D:/showqrcode.jpg")
            .size(1280, 1024)
            .watermark(Positions.BOTTOM_RIGHT, ImageIO.read(new File("D:/watermark.jpg")),
                0.5f) //位置，水印来源，透明度
            .outputQuality(0.8f)
            .toFile("D:/showqrcode_watermark_bottom_right.jpg");
      }
    
    }
    裁剪
    
    import java.io.IOException;
    import net.coobird.thumbnailator.Thumbnails;
    import net.coobird.thumbnailator.geometry.Positions;
    
    public class Client5 {
    
      public static void main(String[] args) throws IOException {
        Thumbnails.of("D:/showqrcode.jpg")
            .sourceRegion(Positions.CENTER, 800, 600) //位置，宽，高
            .size(800, 600)
            .keepAspectRatio(false)
            .toFile("D:/showqrcode_region_center.jpg");
      }
    
    }
    拼接
    
    import java.awt.Graphics;
    import java.awt.image.BufferedImage;
    import java.io.ByteArrayInputStream;
    import java.io.ByteArrayOutputStream;
    import java.io.File;
    import java.io.FileOutputStream;
    import java.io.IOException;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Objects;
    import javax.imageio.ImageIO;
    
    public class Client6 {
    
      public static void main(String[] args) throws Exception {
        byte[] bytes = joinImages(false, new File("D:/showqrcode.jpg"), new File("D:/showqrcode.jpg"));
        if (Objects.nonNull(bytes)) {
          new ByteArrayInputStream(bytes).transferTo(new FileOutputStream("D:/showqrcode_join.jpg"));
        }
      }
    
      /**
       * 将多张图片拼接成一张
       *
       * @param horizontal 是否为水平拼接
       * @param files 文件列表
       * @return 拼接后的文件字节数组
       */
      private static byte[] joinImages(boolean horizontal, File... files) throws IOException {
        if (Objects.isNull(files) || files.length == 0) {
          return null;
        }
        List<BufferedImage> imageList = new ArrayList<>();
        for (File file : files) {
          BufferedImage image = ImageIO.read(file);
          imageList.add(image);
        }
        int height = imageList.get(0).getHeight();
        int width = imageList.get(0).getWidth();
        if (horizontal) {
          width = imageList.stream().mapToInt(BufferedImage::getWidth).sum();
        } else {
          height = imageList.stream().mapToInt(BufferedImage::getHeight).sum();
        }
        //创建拼接后的图片画布，参数分别为宽，高，类型，这里我们使用RGB3元色类型
        BufferedImage resultImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        Graphics graphics = resultImage.getGraphics();
        int previousWidth = 0;
        int previousHeight = 0;
        for (BufferedImage image : imageList) {
          //向画布上画图片
          graphics.drawImage(image, previousWidth, previousHeight, null);
          if (horizontal) {
            previousWidth += image.getWidth();
          } else {
            previousHeight += image.getHeight();
          }
        }
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        ImageIO.write(resultImage, "jpg", output);
        return output.toByteArray();
      }
    }

[java _ - _mouM -]: https://www.cnblogs.com/aknife/p/14676674.html