javaWeb截取视频中画面并保存为图片，作为视频封面

截取视频中画面并保存为图片，作为视频封面

截取视频工具类：

```java
package com.zm.edu.util;import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;import javax.imageio.ImageIO;import com.zm.util.FileUtils;
import lombok.extern.slf4j.Slf4j;
import org.bytedeco.javacv.FFmpegFrameGrabber;
import org.bytedeco.javacv.Frame;
import org.bytedeco.javacv.Java2DFrameConverter;/*** 描述：截取视频中图片作为封面* @author zwh 2021.5.18 10:25*/@Slf4j
public class VideoUtils {/*** main函数中slf4j无法正常显示,这里暂时使用log4j2输出日志,迁移到web项目时,建议使用slf4j*/private static final org.apache.logging.log4j.Logger LOG = org.apache.logging.log4j.LogManager.getLogger();/*** 视频总帧数* */public static String VIDEO_LENGTH = "videoLength";/***视频的宽*/public static String VIDEO_WIDE = "videoWide";/***视频的高*/public static String VIDEO_HIGH = "videoHigh";/***视频的旋转度*/public static String ROTATE = "rotate";/***视频的格式*/public static String FORMAT = "format";/***图片保存路径*/public static String IMG_PATH = "imgPath";/***图片名称*/public static String IMG_NAME = "imgName";/***此视频时长(s/秒)*/public static String DURATION = "duration";/***获取要取得的帧数*/private static final int GET_FRAMES_LENGTH = 1;//测试使用main
//    public static void main(String[] args) {
//        Map screenshot = getScreenshot("C:\\Users\\zhangwenhiu\\Videos\\正能量\\日食.mp4");
//        System.out.println(screenshot.toString());
//    }/*** 
功能:获取一张视频截图并保存同名的jpg文件到视频同目录下
** @param filePath 视频文件全路径* @return*/public static Map getScreenshot(String filePath) {return getScreenshot(filePath, null);}/*** 
功能:获取一张视频截图并保存同名的jpg文件到指定目录
** @param filePath 视频文件地址* @param saveImagePath 截图的图片存放路径(绝对路径,不包含文件名称)* @return*/public static Map getScreenshot(String filePath, String saveImagePath) {LOG.info("视频文件[{}]截图开始", filePath);Map result = new HashMap();FFmpegFrameGrabber grabber;try {grabber = FFmpegFrameGrabber.createDefault(filePath);// 第一帧图片存储位置(也是视频路径)String targerFilePath = filePath.substring(0, filePath.lastIndexOf(FileUtils.DIR_SPERATOR));// 视频文件名String fileName = filePath.substring(filePath.lastIndexOf(FileUtils.DIR_SPERATOR) + 1);// 图片名称String targetFileName = fileName.substring(0, fileName.lastIndexOf(FileUtils.TYPE_SEPARATOR));//String targetFileName =String.valueOf(System.currentTimeMillis());grabber.start();// 视频总帧数int videoLength = grabber.getLengthInFrames();Frame frame = null;int i = 0;while (i < videoLength) {// 过滤前5帧,避免出现全黑的图片,依自己情况而定(每循环一次取一帧)frame = grabber.grabFrame();if ((i > GET_FRAMES_LENGTH) && (frame.image != null)) {break;}i++;}// 视频旋转度String rotate = grabber.getVideoMetadata("rotate");Java2DFrameConverter converter = new Java2DFrameConverter();// 绘制图片BufferedImage bi = converter.getBufferedImage(frame);if (rotate != null) {// 旋转图片bi = rotate(bi, Integer.parseInt(rotate));}// 图片的类型String imageMat = "jpg";// 图片的完整路径String imagePath = targerFilePath + File.separator + targetFileName + FileUtils.TYPE_SEPARATOR + imageMat;if (null != saveImagePath && !"".equals(saveImagePath)) {// 指定路径imagePath = saveImagePath + FileUtils.TYPE_SEPARATOR + imageMat;}// 创建文件File output = new File(imagePath);ImageIO.write(bi, imageMat, output);// 拼接Map信息result.put(VIDEO_LENGTH, videoLength);// 视频的宽result.put(VIDEO_WIDE, bi.getWidth());// 频的高result.put(VIDEO_HIGH, bi.getHeight());// 此视频时长(s/秒)long duration = grabber.getLengthInTime() / (1000 * 1000);// 视频的旋转度result.put(ROTATE, (null == rotate || "".equals(rotate))? "0" : rotate);// 视频的格式result.put(FORMAT, grabber.getFormat());result.put(IMG_PATH, output.getPath());result.put(DURATION, duration);result.put(IMG_NAME,targetFileName + FileUtils.TYPE_SEPARATOR + imageMat);grabber.stop();LOG.info("视频文件[{}]截图结束,图片地址为[{}]", filePath, imagePath);} catch (IOException e) {LOG.error("视频信息帧数处理发生异常 [{}]", e.getMessage());e.printStackTrace();}return result;}// ==================== private method ====================/*** 
功能:根据视频旋转度来调整图片
** @param src 捕获的图像* @param angel 视频旋转度* @return BufferedImage*/private static BufferedImage rotate(BufferedImage src, int angel) {int src_width = src.getWidth(null);int src_height = src.getHeight(null);int type = src.getColorModel().getTransparency();Rectangle rect_des = calcRotatedSize(new Rectangle(new Dimension(src_width, src_height)), angel);BufferedImage bi = new BufferedImage(rect_des.width, rect_des.height, type);Graphics2D g2 = bi.createGraphics();g2.translate((rect_des.width - src_width) / 2, (rect_des.height - src_height) / 2);g2.rotate(Math.toRadians(angel), src_width / 2, src_height / 2);g2.drawImage(src, 0, 0, null);g2.dispose();return bi;}/*** 
功能:计算图片旋转大小
** @param src 屏幕坐标中捕获的矩形区域* @param angel 视频旋转度* @return*/private static Rectangle calcRotatedSize(Rectangle src, int angel) {if (angel >= 90) {if (angel / 90 % 2 == 1) {int temp = src.height;src.height = src.width;src.width = temp;}angel = angel % 90;}double r = Math.sqrt(src.height * src.height + src.width * src.width) / 2;double len = 2 * Math.sin(Math.toRadians(angel) / 2) * r;double angel_alpha = (Math.PI - Math.toRadians(angel)) / 2;double angel_dalta_width = Math.atan((double) src.height / src.width);double angel_dalta_height = Math.atan((double) src.width / src.height);int len_dalta_width = (int) (len * Math.cos(Math.PI - angel_alpha - angel_dalta_width));int len_dalta_height = (int) (len * Math.cos(Math.PI - angel_alpha - angel_dalta_height));int des_width = src.width + len_dalta_width * 2;int des_height = src.height + len_dalta_height * 2;return new java.awt.Rectangle(new Dimension(des_width, des_height));}
}

需要引入的maven依赖```java
org.bytedecojavacv1.5.2org.bytedecojavacpp1.5.2org.bytedecoffmpeg4.2.1-1.5.2windows-x86_64org.bytedecoffmpeg4.2.1-1.5.2linux-x86_64

**注意：**参考地址1中引入的jar包会导致打包时生成的文件过大，可参考地址二进行精简，排除不必要的jar包，引入jar包时-可参照图片中jar包名称，根据部署环境不同选择对应版本。