1.配置ffmpeg的环境变量

2.代码如下

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;


/**
 * @Author LinXin
 * 1.设置视频输出目录
 * 2.获取上传视频的路径以及文件名
 * 3.截取后缀名判断格式
 * 4.ffmpeg不支持的格式先使用mencoder转成AVI格式  丢弃
 * 5.AVI再转成flv格式，同时删除缓存文件           丢弃
 */
public class Video {
    //视频输出目录
    private static final String OutSrc = "C:/Users/LinXin/Desktop/测试视频/flv/";
    //截图输出目录
    private static final String imageOutSrc = "C:/Users/LinXin/Desktop/测试视频/Screen/";
    //视频类型
    private static final String OutType = ".flv";
    //图片类型
    private static final String ImagesType = ".jpg";
    //转码完视频路径
    private static String videoOutSrc = null;


    public static void main(String[] args) {
        String fileName = "C:/Users/LinXin/Desktop/测试视频/video/1.mp4";
        String type = fileName.substring(fileName.lastIndexOf(".") + 1).toLowerCase();
        File orginFile = new File(fileName);

        long start = System.currentTimeMillis();

        if (!orginFile.exists()) {
            System.out.println("文件不存在");
        } else {
            int i = checkType(type);
            if (i == 0) {
                String OutName = fileName.substring(fileName.lastIndexOf("/") +1, fileName.lastIndexOf(".")) + OutType;
                File file = new File(OutSrc + OutName);
                if (file.exists()) {
                    System.out.println("文件已存在");
                } else {
                    String command = "cmd /c ffmpeg -i " + fileName + " -c:v copy -c:a copy " + OutSrc + OutName;
                    if (procedure(command)) {
                        File file1 = new File(fileName);
//                        file1.delete();
                        System.out.println("Success");
                        videoOutSrc = OutSrc+OutName;
                        String fileNameWithNoneType = fileName.substring(fileName.lastIndexOf("/") +1, fileName.lastIndexOf("."));
                        ScreenShot(videoOutSrc,fileNameWithNoneType);
                    } else {
                        System.out.println("Failure");
                    }
                }
            } else {
                System.out.println("文件类型不支持");
            }
        }

        long end = System.currentTimeMillis();

        System.out.println("");
        System.out.println("耗时:"+(end-start)/1000);

    }

    //视频转码，图片截取
    public static boolean procedure(String command) {
        boolean flag = false;
        try {
            Runtime rt = Runtime.getRuntime();
            Process p = rt.exec(command);
            //一个线程去获取正常信息
            new Thread(new Runnable() {
                BufferedReader infoReader = new BufferedReader(new InputStreamReader(p.getInputStream(), "GBK"));
                String line1 = null;

                @Override
                public void run() {
                    try {
                        while ((line1 = infoReader.readLine()) != null) {
                            System.out.println(line1);
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }).start();

            //一个线程去获取错误信息
            new Thread(new Runnable() {
                BufferedReader errorReader = new BufferedReader(new InputStreamReader(p.getErrorStream(), "GBK"));
                String line2 = null;

                @Override
                public void run() {
                    try {
                        while ((line2 = errorReader.readLine()) != null) {
                            System.out.println(line2);
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }).start();

            int exitValue = p.waitFor();
            if (exitValue == 0) {
                flag = true;
            }
            p.destroy();
            System.out.println("Exited with error code " + exitValue);
        } catch (Exception e) {
            System.out.println(e.getMessage());
            flag = false;
        }
        return flag;
    }

    //ffmpeg能解析的格式：（asx，asf，mpg，wmv，3gp，mp4，mov，avi，flv,mkv等）
    private static int checkType(String type) {
        if (type.equals("asx")) {
            return 0;
        } else if (type.equals("asf")) {
            return 0;
        } else if (type.equals("mpg")) {
            return 0;
        } else if (type.equals("wmv")) {
            return 0;
        } else if (type.equals("3gp")) {
            return 0;
        } else if (type.equals("mp4")) {
            return 0;
        } else if (type.equals("mov")) {
            return 0;
        } else if (type.equals("avi")) {
            return 0;
        } else if (type.equals("flv")) {
            return 0;
        } else if (type.equals("mkv")) {
            return 0;
        }
        return 1;
    }


    //视频截图
    public static boolean ScreenShot(String videoPath,String imagesPath){
        boolean flag = false;
        String command = "ffmpeg -ss 00:00:40 -t 0.001 -i "+videoPath+" -y -f image2 -q:v 2 -s 1920x1080 "+imageOutSrc+imagesPath+ImagesType;
        if(procedure(command)){
            System.out.println("ScreentShot Success");
        }
        return flag;
    }
}