hera-rtsp-relay

4HERA RTSP Relay

Install

npm install -S hera-rtsp-relay express

You don't need to install ffmpeg!

Example

const express = require('express');
const app = express();

const { proxy, scriptUrl } = require('hera-rtsp-relay')(app);

const handler = proxy({
  url: `rtsp://admin:admin@10.0.1.2:554/feed`,
  // if your RTSP stream need credentials, include them in the URL as above
  verbose: false,
});

// the endpoint our RTSP uses
app.ws('/api/stream', handler);

// this is an example html page to view the stream
app.get('/', (req, res) =>
  res.send(`
  <canvas id='canvas'></canvas>

  <script src='${scriptUrl}'></script>
  <script>
    loadPlayer({
      url: 'ws://' + location.host + '/api/stream',
      canvas: document.getElementById('canvas')
    });
  </script>
`),
);

app.listen(2000);

Usage with many cameras

If you have hundreds of cameras and don't want to define a seperate route for each one, you can use a dynamic URL:

app.ws('/api/stream/:cameraIP', (ws, req) =>
  proxy({
    url: `rtsp://${req.params.cameraIP}:554/feed`,
  })(ws),
);

Usage with many clients

You may see a MaxListenersExceededWarning if the relay is re-transmitting 10+ streams at once, or if 10+ clients are watching.

This is expected, and you can silence the warning by adding process.setMaxListeners(0); to your code.

Improving the video quality

Depending on your network configuration, you can try the following options to improve the stream quality:

// try this:
app.ws('/api/stream', proxy({ additionalFlags: ['-q', '1'] }));

// or this:
app.ws('/api/stream', proxy({ transport: 'tcp' }));

Note that both these methods will use more bandwidth.

SSL

If you want to use HTTPS, you will need to change the stream URL to wss://, like the following example:

const rtspRelay = require('hera-rtsp-relay');
const express = require('express');
const https = require('https');
const fs = require('fs');

const key = fs.readFileSync('./privatekey.pem', 'utf8');
const cert = fs.readFileSync('./fullchain.pem', 'utf8');
const ca = fs.readFileSync('./chain.pem', 'utf8'); // required for iOS 15+

const app = express();
const server = https.createServer({ key, cert, ca }, app);

const { proxy, scriptUrl } = rtspRelay(app, server);

app.ws('/api/stream', proxy({ url: 'rtsp://1.2.3.4:554' }));

app.get('/', (req, res) =>
  res.send(`
  <canvas id='canvas'></canvas>

  <script src='${scriptUrl}'></script>
  <script>
    loadPlayer({
      url: 'wss://' + location.host + '/api/stream',
      canvas: document.getElementById('canvas')
    });
  </script>
`),
);

server.listen(443);