java视频格式转码，设置编码格式

项目上传后的视频不能在video标签里面播放，视频格式是MP4。重新编码之后就可以了

package com.video.util;

import org.bytedeco.javacv.FFmpegFrameGrabber;
import org.bytedeco.javacv.FFmpegFrameRecorder;
import org.bytedeco.javacpp.*;
import org.bytedeco.javacv.Frame;


public class VideoConvert {

    private boolean isStart = true;

    public void frameRecord(String inputFile, String outputFile)
               throws Exception, org.bytedeco.javacv.FrameRecorder.Exception {
                       // 获取视频源
                       FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(inputFile);
                       grabber.setOption("rtsp_transport","tcp");
                       //速度
                       grabber.setFrameRate(30);
                       //码率
                       grabber.setVideoBitrate(3000000);
                       // 流媒体输出地址，分辨率（长，高），是否录制音频（0:不录制/1:录制）
                      FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(outputFile, 1280, 720, 1);
                       recorder.setFrameRate(30);
                      recorder.setVideoBitrate(3000000);
                      //编码格式
                      recorder.setVideoCodec(avcodec.AV_CODEC_ID_H264); //avcodec.AV_CODEC_ID_H264  //AV_CODEC_ID_MPEG4
                      recordByFrame(grabber, recorder);
     }

     private void recordByFrame(FFmpegFrameGrabber grabber, FFmpegFrameRecorder recorder)
               throws Exception, org.bytedeco.javacv.FrameRecorder.Exception {
          try {// 建议在线程中使用该方法
               
               grabber.start();
               recorder.start();
               //CanvasFrame canvas = new CanvasFrame("摄像头");//新建一个窗口
          //     canvas.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
               //canvas.setAlwaysOnTop(true);

               long t1 = System.currentTimeMillis();
               
               Frame frame = null;
               

               while (isStart && (frame = grabber.grabFrame()) != null) {
                    long t2 = System.currentTimeMillis();
                       if(t2-t1 > 2*60*60*1000){
                                  break;
                            }else{
                                 recorder.record(frame);
                                  //TODO your work
                            }
                    //canvas.showImage(grabber.grab());//获取摄像头图像并放到窗口上显示， 这里的Frame frame=grabber.grab(); frame是一帧视频图像
               }
               recorder.stop();
               grabber.stop();
               
          } finally {
               if (grabber != null) {
                    grabber.stop();
               }
    }
    }

}

当然首先得引入依赖了

<dependencies>
    <dependency>
        <groupId>org.bytedeco</groupId>
        <artifactId>javacv</artifactId>
        <version>1.4.1</version>
    </dependency>
    <dependency>
        <groupId>org.bytedeco</groupId>
        <artifactId>javacpp</artifactId>
        <version>1.4.1</version>
    </dependency>
    <dependency>
        <groupId>org.bytedeco.javacpp-presets</groupId>
        <artifactId>opencv-platform</artifactId>
        <version>3.4.1-1.4.1</version>
    </dependency>
    <dependency>
        <groupId>org.bytedeco.javacpp-presets</groupId>
        <artifactId>ffmpeg-platform</artifactId>
        <version>3.4.2-1.4.1</version>
    </dependency>
</dependencies>