Java视频流在线播放(分断下载,断点续传)

思路：前端使用video标签，访问后端视频接口地址，并附带视频路径参数，进行播放（后端接口需要支持分段，否则前端视频不能拖动进度条）。

第一步：完成后端方法。

public void play(String path, HttpServletRequest request, HttpServletResponse response) {                String fileName ="测试.mp4";        RandomAccessFile targetFile = null;        OutputStream outputStream = null;        try {            outputStream = response.getOutputStream();            response.reset();            //获取请求头中Range的值            String rangeString = request.getHeader("Range");             //打开文件            File file = new File(path);            if (file.exists()) {                //使用RandomAccessFile读取文件                targetFile = new RandomAccessFile(file, "r");                long fileLength = targetFile.length();                long requestSize = (int)fileLength;                //分段下载视频                if (StringUtils.hasText(rangeString)) {                    //从Range中提取需要获取数据的开始和结束位置                    long requestStart = 0, requestEnd = 0;                    String[] ranges = rangeString.split("=");                    if (ranges.length > 1) {                        String[] rangeDatas = ranges[1].split("-");                        requestStart = Integer.parseInt(rangeDatas[0]);                        if (rangeDatas.length > 1) {requestEnd = Integer.parseInt(rangeDatas[1]);                        }                    }                    if (requestEnd != 0 && requestEnd > requestStart) {                        requestSize = requestEnd - requestStart + 1;                    }                    //根据协议设置请求头                    response.setHeader(HttpHeaders.ACCEPT_RANGES, "bytes");                    response.setHeader(HttpHeaders.CONTENT_TYPE, "video/mp4");                    if (!StringUtils.hasText(rangeString)) {                        response.setHeader(HttpHeaders.CONTENT_LENGTH, fileLength + "");                    } else {                        long length;                        if (requestEnd > 0) {length = requestEnd - requestStart + 1;response.setHeader(HttpHeaders.CONTENT_LENGTH, "" + length);response.setHeader(HttpHeaders.CONTENT_RANGE,    "bytes " + requestStart + "-" + requestEnd + "/" + fileLength);                        } else {length = fileLength - requestStart;response.setHeader(HttpHeaders.CONTENT_LENGTH, "" + length);response.setHeader(HttpHeaders.CONTENT_RANGE,    "bytes " + requestStart + "-" + (fileLength - 1) + "/" + fileLength);                        }                    }                    //文段下载视频返回206                    response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT);                    //设置targetFile，从自定义位置开始读取数据                    targetFile.seek(requestStart);                } else {                    //如果Range为空则下载整个视频                    response.setHeader(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + fileName + "");                    //设置文件长度                    response.setHeader(HttpHeaders.CONTENT_LENGTH, String.valueOf(fileLength));                }                 //从磁盘读取数据流返回                byte[] cache = new byte[4096];                try {                    while (requestSize > 0) {                        int len = targetFile.read(cache);                        if (requestSize < cache.length) {outputStream.write(cache, 0, (int)requestSize);                        } else {outputStream.write(cache, 0, len);if (len < cache.length) {    break;}                        }                        requestSize -= cache.length;                    }                } catch (IOException e) {                  }            } else {                throw new RuntimeException("文件路劲有误");            }            outputStream.flush();        } catch (Exception e) {         } finally {            if (outputStream != null) {                try {                    outputStream.close();                } catch (IOException e) {                 }            }            if (targetFile != null) {                try {                    targetFile.close();                } catch (IOException e) {                 }            }        }     }

第二步: 完成前端

大坑注意：正常情况到这里就已经正常播放视频了，但是博主却发现了一个问题，我本地录制的视频可以播放，从摄像头截取下来的视频却不可以播放，点击播放时后台一直报java.io.IOException: 您的主机中的软件中止了一个已建立的连接，这种情况一般是前端主动断开连接造成的。

百思不得其解时突然想到是不是视频的问题，果然，发现视频监控截取下来的虽然是.mp4后缀，但是视频编码是MPEG-PS的编码格式，而vdieo标签目前只支持三种视频格式

由于前端不能播放这种视频，所以主动断开了链接，所以这里有涉及到了视频转码。

首先引入依赖：

  org.bytedeco  javacv  1.4.1  org.bytedeco  javacpp  1.4.1

编写转码工具类 

package com.video.tool.hik;import cn.hutool.http.HttpUtil;import org.bytedeco.javacpp.avcodec;import org.bytedeco.javacv.*;import org.slf4j.Logger;import org.slf4j.LoggerFactory;public class VideoEncodeUtil {        public static void encode(String inputFile, String outputFile, String id) throws Exception {        final Logger logger = LoggerFactory.getLogger(DownLoadCallBack.class);        FFmpegFrameGrabber grabber = FFmpegFrameGrabber.createDefault(inputFile);        Frame captured_frame;        FFmpegFrameRecorder recorder = null;        try {            grabber.start();            recorder = new FFmpegFrameRecorder(outputFile, grabber.getImageWidth(), grabber.getImageHeight(),                   grabber.getAudioChannels());            recorder.setVideoCodec(avcodec.AV_CODEC_ID_H264);            recorder.setFormat("mp4");            recorder.setFrameRate(grabber.getFrameRate());            recorder.setSampleRate(grabber.getSampleRate());            recorder.setVideoBitrate(grabber.getVideoBitrate());            recorder.setAspectRatio(grabber.getAspectRatio());            recorder.setAudioBitrate(grabber.getAudioBitrate());            recorder.setAudioOptions(grabber.getAudioOptions());            recorder.setAudioCodec(avcodec.AV_CODEC_ID_AAC);            recorder.start();            while (true) {                captured_frame = grabber.grabFrame();                if (captured_frame == null) {                    logger.info("转码成功");                    break;                }                recorder.record(captured_frame);            }        } catch (FrameRecorder.Exception e) {            e.printStackTrace();        } finally {            if (recorder != null) {                try {                    recorder.close();                } catch (Exception e) {                    logger.info("recorder.close异常");                }            }            try {                grabber.close();            } catch (FrameGrabber.Exception e) {                logger.info("frameGrabber.close异常");            }        }    }}

来源地址：https://blog.csdn.net/dongcsdn123/article/details/132207675