1.在build.gradle中添加依赖：

    implementation group: 'javax.media', name: 'jai_codec', version: '1.1.3'implementation group: 'com.sun', name: 'jai_core', version: '1.1.3'implementation group: 'javax.media', name: 'jai_imageio', version: '1.1'implementation 'xx.com.sun:jimi:1.0'

最后一个依赖jimi:1.0很难找，如果没有文章上方有jar包可以下载手动导入

手动导入的方式为：

        1.和src平级创建lib目录，将所需jar包拷贝到此目录

        2.在build.gradle中通过下面语句进行导入

implementation fileTree(dir: 'lib', include: ['*.jar'])

2.创建工具类，进行格式转换

import com.sun.media.jai.codec.*;
import org.springframework.stereotype.Component;import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.ImageWriter;
import javax.imageio.stream.FileImageInputStream;
import javax.imageio.stream.FileImageOutputStream;
import java.io.File;
import java.util.ArrayList;
import java.util.List;@Component
public class TifConverterRefreshFilter {/*** tif to jpg.*/public List<String> tifToJpg(String oldFilePath, String fileName, String newFilePath) throws Exception {if (oldFilePath == null || fileName.isEmpty()) {return null;}List<String> jpgList = new ArrayList<>();SeekableStream ss = new FileSeekableStream(oldFilePath);TIFFDecodeParam param0 = null;TIFFEncodeParam param = new TIFFEncodeParam();ImageDecoder dec = ImageCodec.createImageDecoder("tiff", ss, param0);int count = dec.getNumPages();param.setCompression(TIFFEncodeParam.COMPRESSION_GROUP4);param.setLittleEndian(false); // Intelfor (int i = 0; i < count; i++) {File file = new File(oldFilePath);ImageReader reader = ImageIO.getImageReadersByFormatName("tiff").next();FileImageInputStream inputStream = new FileImageInputStream(file);reader.setInput(inputStream);reader.read(i);ImageWriter writer = ImageIO.getImageWritersByFormatName("jpg").next();String pictureUrl = fileName + "_" + i;FileImageOutputStream fs = new FileImageOutputStream(new File(newFilePath + pictureUrl + ".jpg"));writer.setOutput(fs);writer.write(reader.read(i));fs.close();reader.dispose();writer.dispose();jpgList.add(pictureUrl);}ss.close();return jpgList;}
}

所需jar包：无法下载，积分不够的私聊我，我单独发给你们