Multithreading Node.js ESP32-CAM Video over Websockets

In this article, we’ll explore how to use multithreading in Node.js to stream video from an ESP32-CAM to a web browser over Websockets.

ESP32-CAM

The ESP32-CAM is a small development board that combines an ESP32 microcontroller and a camera module. It can be used to capture images and video and transmit them over Wi-Fi.

Node.js

Node.js is a popular runtime environment for server-side and networking applications. It provides a scalable and flexible platform for building web applications.

Websockets

Websockets are a communication protocol that provides full-duplex communication channels over a single TCP connection. They are commonly used to enable real-time communication between a client and a server.

Multithreading in Node.js

While Node.js is single-threaded by default, it is possible to use worker threads to take advantage of multi-core systems and improve the performance of CPU-bound tasks. This can be particularly useful in applications that involve intensive processing, such as video streaming.

Streaming Video over Websockets

To stream video from an ESP32-CAM to a web browser over Websockets using Node.js, we can create a server that captures video frames from the camera, processes them using multithreading, and transmits them to the client using Websockets.

Code Example

      
        const http = require('http');
        const express = require('express');
        const WebSocket = require('ws');
        const { Worker, isMainThread, parentPort, workerData } = require('worker_threads');

        if (isMainThread) {
          const worker = new Worker('video-processing.js', { workerData: /* data */ });
          worker.on('message', (message) => {
            /* handle message */
          });
        } else {
          /* video processing logic */
          parentPort.postMessage(/* message */);
        }
      
    

Conclusion

Multithreading in Node.js can be a powerful tool for optimizing the performance of applications that involve intensive processing, such as video streaming. By using worker threads and Websockets, we can efficiently stream video from an ESP32-CAM to a web browser in real-time.