How to stream video data to a video element?

问题

I have a Node.js process which outputs a video stream into my Node.js app.

On the client end, there is a <video> tag. I would like to stream the video from Node.js into the src attribute of the video tag. My previous experience tells me that we must use the blob object for this. However, I'm not a hundred percent certain how and why I would use it.

Another possible solution I'm thinking of is to create some sort of a temporary file on my server, then write the stream to that file, then serve that file as the source for the video. However, that doesn't seem intuitive. I was wondering, then, if there is a more established solution for an issue like this.

回答1:

Probably you might want to look at the following options:

BinaryJS. It's bidrectional realtime binary data transfer tool based on websockets.
JSMpeg stream-server (in case of capturing) from Phoboslab guys. All you need to do is start ffmpeg and point it to the domain and port where the nodejs script is running. More info you can find here.
Pipe a stream directly. Good answer is posted here. In few words you just need to specify Accept-Ranges, Content-Range, Content-Length and Content-Type headers, then create relevant Read stream (with start and end options) and pipe it to the response object.

回答2:

m3u8 format is commonly used for streaming. Video streaming/transcoding is a resource intensive thing. I would suggest you to use third party service to do so, if you have that option.

回答3:

I've actually tried this at a hackathon two weeks ago. I ended up barely getting this flv stream to work, which I've posted below. My intent was to make a library to automate much of the processes this would entail.

As you can see, I've opened a new port on the server to handle the separate stream of data flowing to the client. This is reflected in the client's src tag.

THREE THINGS YOU NEED:

This Linux version of ffmpeg.
Flowplayer on the js side.

npm fluent-ffmpeg

// StreamServer.js

var express = require('express'),
  app = express(),
  ffmpeg = require('fluent-ffmpeg');

module.exports = function () {
    app.stream(req, res)
    {
        res.contentType('flv');
        // make sure you set the correct path to your video file storage 
        var pathToMovie = '/path/to/storage/' + req.params.filename;
        var proc = ffmpeg(pathToMovie)
          // use the 'flashvideo' preset (located in /lib/presets/flashvideo.js) 
          .preset('flashvideo')
          // setup event handlers 
          .on('end', function () {
              console.log('file has been converted succesfully');
          })
          .on('error', function (err) {
              console.log('an error happened: ' + err.message);
          })
          // save to stream 
          .pipe(res, { end: true });

    };

}

//routes.js

'use strict';
var stream = require('../controllers/streaming.server.controller'),
 streamServer = require('../controllers/StreamServer.js'),
express = require('express');

//streaming.server.controller.js

module.exports = function (app) {
    app.get('/api/stream', function (req, res) {
        streamServer.stream(req, res);
    });
};

var path = require('path'),
 express = require('express'),
 app = express(),
 routes = require('../routes/routes.js')(app),
 ffmpeg = require('fluent-ffmpeg');

app.listen(4000);

EDIT: Client side part:

https://github.com/fluent-ffmpeg/node-fluent-ffmpeg/tree/master/examples/flowplayer

<html>
    <head>
        <meta http-equiv="content-type" content="text/html; charset=UTF-8">
        <script type="text/javascript" src="/flowplayer.min.js"></script>
        <title>node-fluent-ffmpeg</title>
    </head>
    <body>

        <!-- this A tag is where your Flowplayer will be placed. it can be anywhere -->
        <a  
             href="http://localhost:4000/api/stream"
             style="display:block;width:520px;height:330px"  
             id="player"> 
        </a> 

        <!-- this will install flowplayer inside previous A- tag. -->
        <script>
            flowplayer("player", "/flowplayer.swf");
        </script>
    </body>
</html>

(Just change the href attribute)

来源：https://stackoverflow.com/questions/36274810/how-to-stream-video-data-to-a-video-element

标签

javascript

node.js

blob