Livestream webcam via webm to browsers

Mon, Jan 7, 2013

Here’s a work in progress: livestream webcam video to browsers using Node.js. From here. Ubuntu requires the ‘nodejs’ executable instead of just ‘node’

var express = require('express')
var net = require('net');
var child = require('child_process');

var cmd = 'gst-launch-0.10';
var args = '';
var options = null;

var app = express();

app.get('/', function(req, res) {
  var date = new Date();

  res.writeHead(200, {
    'Date':date.toUTCString(),
    'Connection':'close',
    'Cache-Control':'private',
    'Content-Type':'video/webm',
    'Server':'CustomStreamer/0.0.1',
    });

  var server = net.createServer(function (socket) {
    socket.on('data', function (data) {
      res.write(data);
    });
    socket.on('close', function(had_error) {
      res.end();
    });
  });

  server.maxConnections = 1;

  server.listen(function() {
    args =
    ['v4l2src device=/dev/video0',
    '!', 'video/x-raw-rgb,framerate=30/1',
    '!', 'ffmpegcolorspace',
    '!', 'vp8enc', 'speed=2',
    '!', 'queue2',
    '!', 'm.', 'audiotestsrc', 'is-live=1',
    '!', 'audioconvert',
    '!', 'vorbisenc',
    '!', 'queue2',
    '!', 'm.', 'webmmux', 'name=m', 'streamable=true',
    '!', 'tcpclientsink', 'host=localhost',
    'port='+server.address().port];

    var gstMuxer = child.spawn(cmd, args, options);

    gstMuxer.stderr.on('data', onSpawnError);
    gstMuxer.on('exit', onSpawnExit);

    res.connection.on('close', function() {
      gstMuxer.kill();
    });
  });
});

app.listen(9001);

function onSpawnError(data) {
  console.log(data.toString());
}

function onSpawnExit(code) {
  if (code != null) {
    console.error('GStreamer error, exit code ' + code);
  }
}

process.on('uncaughtException', function(err) {
  console.debug(err);
});