分享一个上传图片，图片压缩Unsupported Image Type解决方案

文件上传是一个最基本的功能，往往我们需要对图片进行压缩，来加快移动端的加载速度。

SprimgMVC图片上传可以参考SpringMVC传值

从这里开始

System.out.println("文件大小: " + file.getSize());            System.out.println("文件类型: " + file.getContentType());            System.out.println("表单名称: " + file.getName());            System.out.println("文件原名: " + file.getOriginalFilename());            if (!file.getContentType().contains("image")) {                return BaseReturn.response(ErrorCode.FAILURE, "不支持的图片类型：" + file.getContentType());            }            String image = ImageService.saveImage(request, file, uploadPath);

相关依赖

    <!-- 图片压缩 -->    <dependency>        <groupId>net.coobird</groupId>        <artifactId>thumbnailator</artifactId>        <version>0.4.8</version>    </dependency>    <!-- cmyk格式图片转换 -->    <dependency>        <groupId>com.twelvemonkeys.imageio</groupId>        <artifactId>imageio-jpeg</artifactId>        <version>3.3</version>    </dependency>    <dependency>        <groupId>com.twelvemonkeys.imageio</groupId>        <artifactId>imageio-tiff</artifactId>        <version>3.3</version>    </dependency>

ImageService

package com.jrbac.service;import java.awt.image.BufferedImage;import java.io.File;import java.io.IOException;import javax.imageio.ImageIO;import javax.imageio.stream.ImageOutputStream;import javax.servlet.http.HttpServletRequest;import org.apache.commons.io.FileUtils;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.web.multipart.MultipartFile;import com.jrbac.util.UUIDGenerator;import net.coobird.thumbnailator.Thumbnails;public class ImageService {    private static final Logger logger = LoggerFactory.getLogger(ImageService.class);    /**     * @param request     * @param file     * @param uploadPath     *            形如这样的/assets/upload/image/     * @return /assets/upload/image/abc.jpg     * @throws IOException     */    public static String saveImage(HttpServletRequest request, MultipartFile file, String uploadPath) {        // 如果用的是Tomcat服务器，则文件会上传到\\%TOMCAT_HOME%\\webapps\\YourWebProject\\uploadPath\\文件夹中        // String fileName = file.getOriginalFilename();        // String fileExt[] = fileName.split("\\.");        String ext = file.getContentType().split("\\/")[1];        String newFileName = UUIDGenerator.getUUID() + "." + ext;        String realPath = request.getSession().getServletContext().getRealPath(uploadPath);        String filePathAndName = null;        if (realPath.endsWith(File.separator)) {            filePathAndName = realPath + newFileName;        } else {            filePathAndName = realPath + File.separator + newFileName;        }        logger.info("-----上传的文件:{}-----", filePathAndName);        try {            // 先把文件保存到本地            FileUtils.copyInputStreamToFile(file.getInputStream(), new File(realPath, newFileName));        } catch (IOException e1) {            logger.error("-----文件保存到本地发生异常:{}-----", e1.getMessage());        }        int big = 2 * 1024 * 1024; // 2M以上就进行0.6压缩        if (file.getSize() > big) {            thumbnail(filePathAndName, 0.6f);        } else {            thumbnail(filePathAndName, 0.8f);        }        return uploadPath + newFileName;    }    private static void thumbnail(String filePathAndName, double size) {        try {            Thumbnails.of(filePathAndName).scale(size).toFile(filePathAndName);        } catch (IOException e) {            logger.error("-----读取图片发生异常:{}-----", e.getMessage());            logger.info("-----尝试cmyk转化-----");            File cmykJPEGFile = new File(filePathAndName);            try {                BufferedImage image = ImageIO.read(cmykJPEGFile);                ImageOutputStream output = ImageIO.createImageOutputStream(cmykJPEGFile);                if (!ImageIO.write(image, "jpg", output)) {                    logger.info("-----cmyk转化异常:{}-----");                }                Thumbnails.of(image).scale(0.4f).toFile(filePathAndName);                logger.info("-----cmyk转化成功-----");            } catch (IOException e1) {                logger.info("-----cmyk转化异常:{}-----", e1.getMessage());            }        }    }}

这里有一点需要解释一下

FileUtils.copyInputStreamToFile(file.getInputStream(), new File(realPath, newFileName));

会将图片保存到本地，

这一步没问题

问题会发生在

Thumbnails.of(filePathAndName).scale(size).toFile(filePathAndName);

大部分情况下是不会出问题的，如果

P过的图片保存为jpg格式时，默认的模式是CMYK模式

就会报如下错误

javax.imageio.IIOException: Unsupported Image Type

这里采用https://github.com/haraldk/TwelveMonkeys工具解决

参考文献

SpringMVC传值

imageIO异常：Unsupported Image Type, 不支持图像类型

java下cmyk图片读取和转换rgb

https://github.com/haraldk/TwelveMonkeys