![[文件上传工具类] Thumbnails之上传图片后压缩等处理](https://700zi.400zi.cn/uploadfile/img/15/204/9debee5d189924105ff1a980cb0f0a87.jpg)
目录
1.Thumbnails简介
2. 导入依赖
3. 图片压缩工具类代码
4. 参数介绍
1.Thumbnails简介
图像处理API，可以实现图像常用操作(图片信息、扩大、缩小、压缩等)
2. 导入依赖
<!--文件上传--><dependency><groupId>commons-fileupload</groupId><artifactId>commons-fileupload</artifactId><version>1.3.3</version></dependency><!-- 压缩图片大小 --><dependency><groupId>net.coobird</groupId><artifactId>thumbnailator</artifactId><version>0.4.8</version></dependency>
3. 图片压缩工具类代码
package *;import net.coobird.thumbnailator.Thumbnails;import mons.fileupload.FileItem;import mons.fileupload.FileItemFactory;import mons.fileupload.disk.DiskFileItemFactory;import org.springframework.beans.factory.annotation.Value;import org.springframework.cloud.context.config.annotation.RefreshScope;import org.ponent;import org.springframework.web.multipart.MultipartFile;import org.springframework.monsMultipartFile;import javax.annotation.PostConstruct;import java.io.*;/*** 压缩工具类** @Author pzy* @Description: TODO 需要多次测试调整参数* @Version 0.1.0*/public class CompressionUtils {private static MultipartFile getMulFileByFile(InputStream fis, String fieldName, String contentType, String fileName) {FileItem fileItem = createFileItem(fis, fieldName, contentType, fileName);return new CommonsMultipartFile(fileItem);}private static FileItem createFileItem(InputStream fis, String fieldName, String contentType, String fileName) {FileItemFactory factory = new DiskFileItemFactory(16, null);FileItem item = factory.createItem(fieldName, contentType, false, fileName);int bytesRead = 0;byte[] buffer = new byte[8192];try {OutputStream os = item.getOutputStream();while ((bytesRead = fis.read(buffer, 0, 8192)) != -1) {os.write(buffer, 0, bytesRead);}os.close();fis.close();} catch (IOException e) {e.printStackTrace();}return item;}public static MultipartFile compressImg(MultipartFile multiFile) {// 压缩图片InputStream inputStream = null;ByteArrayOutputStream bos = null;MultipartFile multipartFile = null;InputStream fileInput = null;try {inputStream = multiFile.getInputStream();bos = new ByteArrayOutputStream();// 压缩图片核心代码Thumbnails.Builder<? extends InputStream> builder = Thumbnails.of(inputStream);builder.scale(1f) //等比缩放.outputQuality(0.3f) //1高质量 -> 0 低质量.toOutputStream(bos);fileInput = new ByteArrayInputStream(bos.toByteArray());// 转换 MultipartFileString fieldName = multiFile.getName();String fileName = multiFile.getOriginalFilename();String contentType = multiFile.getContentType();multipartFile = getMulFileByFile(fileInput, fieldName, contentType, fileName);} catch (IOException e) {e.printStackTrace();} finally {try {if (inputStream != null) {inputStream.close();}if (bos != null) {bos.close();}if (fileInput != null) {fileInput.close();}} catch (IOException e) {e.printStackTrace();}}return multipartFile;}}
4. 参数介绍
scale缩放比例 ：大于1是放大，小于1是缩小
-> 4.1 创建builder对象
Builder<File> bdFile = Thumbnails.of(files.getAbsolutePath())
-> 4.2 方法也可以直接使用
package ;import net.coobird.thumbnailator.Thumbnails;import net.coobird.thumbnailator.geometry.Position;import java.awt.image.BufferedImage;import java.io.File;import java.io.IOException;import java.util.Objects;/*** 压缩图片处理的公用方法* 理解成注释也行* <p>* <p>* linux批处理指令 //find /thumbnail/ -regex '.*\(jpg\|JPG\|png\|PNG\|jpeg\)' -size +49k -exec convert -resize "x300>" -quality 75 {} {} \;** @Author pzy* @Description: TODO* @Version 0.1.0*/public class CompressionMethod {//代码//<dependency>// <groupId>net.coobird</groupId>// <artifactId>thumbnailator</artifactId>// <version>0.4.8</version>//</dependency>/*** @param scale 缩放比例 ：大于1是放大，小于1是缩小* @param fromFile 源图片路径* @param tofile 目的图片路径* @throws IOException <br>* @Title: scale<br>* @Description: 按比例缩放<br>*/public static void scale(double scale, String fromFile, String tofile) throws IOException {Thumbnails.of(fromFile).scale(0.5).toFile(tofile);}/*** @param height 图片高 px* @param width 图片宽 px* @param fromFile* @param tofile* @throws IOException <br>* @Title: size<br>* @Description: 按大小尺寸缩放<br>*/public static void size(int height, int width, String fromFile, String tofile) throws IOException {Thumbnails.of(fromFile).size(width, height).toFile(tofile);}/*** @param height 图片缩小高度至 px* @param fromFile* @param tofile* @throws IOException <br>* @Title: height<br>* @Description: 按指定高度缩小图片，等比例调整图片宽度<br>*/public static void height(int height, String fromFile, String tofile) throws IOException {Thumbnails.of(fromFile).height(height).toFile(tofile);}/*** @param width 图片缩小宽度至 px* @param fromFile* @param tofile* @throws IOException <br>* @Title: width<br>* @Description: 按指定宽度缩小图片，等比例调整图片高度<br>*/public static void width(int width, String fromFile, String tofile) throws IOException {Thumbnails.of(fromFile).width(width).toFile(tofile);}/*** @param quality 图片质量比例，1 为高质量，越接近0图片质量越低* @param fromFile* @param tofile* @throws IOException <br>* @Title: outputQuality<br>* @Description: 设置图片质量，一般与缩放功能同时使用<br>*/public static void outputQuality(float quality, String fromFile, String tofile) throws IOException {Thumbnails.of(fromFile).outputQuality(quality).toFile(tofile);}/*** @param position 位置* @param image 图片* @param opacity 透明度* @param fromFile* @param tofile* @throws IOException <br>* @Title: watermark<br>* @Description: 添加图片水印<br>*/public static void watermark(Position position, BufferedImage image, float opacity, String fromFile, String tofile) throws IOException {Thumbnails.of(fromFile).watermark(position, image, opacity).toFile(tofile);}/*** @param angle 正数则为顺时针，负数则为逆时针* @param fromFile* @param tofile* @throws IOException <br>* @Title: rotate<br>* @Description: 图片旋转 <br>*/public static void rotate(double angle, String fromFile, String tofile) throws IOException {Thumbnails.of(fromFile).rotate(angle).toFile(tofile);}/*** @param position 图片位置* @param width 裁剪宽* @param height 裁剪高* @param fromFile* @param tofile* @throws IOException <br>* @Title: sourceRegion<br>* @Description: 裁剪图片<br>*/public static void sourceRegion(Position position, int width, int height, String fromFile, String tofile) throws IOException {//Thumbnails.of(fromFile).sourceRegion(Positions.TOP_CENTER, width, height).toFile(tofile);Thumbnails.of(fromFile).sourceRegion(position, width, height).toFile(tofile);}/*** @param fromDir* @param tofile* @throws IOException <br>* @Title: listfiles<br>* @Description: 批量处理文件，可与前几个方法结合起来处理<br>*/public static void listfiles(String fromDir, String tofile) throws IOException {Thumbnails.of(Objects.requireNonNull(new File(fromDir).listFiles())).toFile(tofile);}}
