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java 的图片BufferedImage方式缩小后有严重色差/严重偏红怎么办

今天遇到的两个问题:

java 的图片BufferedImage方式缩小后有严重色差/严重偏红怎么办
java 的图片BufferedImage方式缩小后有严重色差/严重偏红怎么办

图片本如图1所示,

java处理后,变成了图2所示,严重失真,偏红,怎么办?

以上直接上关键代码:

原来处理的代码:

import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;

public class BufferedImageTool {

    public static void resize(String imgPath, double factor) throws IOException {

        File file = new File(imgPath);
        BufferedImage bufferedImage = ImageIO.read(file);

        int width = (int) (bufferedImage.getWidth() * factor);
        int height = (int) (bufferedImage.getHeight() *factor);

        BufferedImage bufferedImage1 = resize(bufferedImage, width, height);


        File outfile = new File("image.jpg");
        ImageIO.write(bufferedImage1, "jpg", outfile);
    }


    /**
     */
    public static BufferedImage resize(BufferedImage img, int newW, int newH) {
        Image tmp = img.getScaledInstance(newW, newH, Image.SCALE_SMOOTH);
        BufferedImage dimg = new BufferedImage(newW, newH, BufferedImage.TYPE_INT_ARGB);

        Graphics2D g2d = dimg.createGraphics();
        g2d.drawImage(tmp, 0, 0, null);
        g2d.dispose();

        return dimg;
    }

}
      

后来找到了一个库,效果非常好,处理完后的图片大小比图2还稍微小一点。

但却没有色差,几乎跟原图完全一样,效果很好。

java 的图片BufferedImage方式缩小后有严重色差/严重偏红怎么办

直接上代码,

依赖 ​

​thumbnailator​

​库。

<!-- https://mvnrepository.com/artifact/net.coobird/thumbnailator -->
        <dependency>
            <groupId>net.coobird</groupId>
            <artifactId>thumbnailator</artifactId>
            <version>0.4.14</version>
        </dependency>      

上代码:

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import net.coobird.thumbnailator.Thumbnails;

/**
 *
 */
public class ThumbnailsTool {


    public static void resize(String imgPath, double factor) throws IOException {

        File localTempFile = new File(imgPath);

        BufferedImage bufferedImage = ImageIO.read(localTempFile);
        int width = (int) (bufferedImage.getWidth() * factor);
        int height = (int) (bufferedImage.getHeight() * factor);

        // BufferedImage 第三方库压缩图片画幅。JDK自带的会有严重色差
        Thumbnails.of(localTempFile)
            .size(width, height)
            .outputFormat("jpg")
            .toFile(new File("image2.jpg"));

    }

}
      

入口Main函数:

import image.ImageHelper;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.URISyntaxException;
import java.util.UUID;
import net.coobird.thumbnailator.Thumbnails;

public class Starter {

    public static void main(String[] args) throws IOException, URISyntaxException {

        String imageUrl = "D:\\MyJava\\java-image\\sky.jpg";

        //1. BufferedImage的形式处理
        BufferedImageTool.resize(imageUrl, 0.5);

        //2. Thumbnails 方式的处理
        ThumbnailsTool.resize(imageUrl, 0.5);
    }
}
      

产生的文件截图如下: