How to access webcam and grab an image using HTML5 and Javascript

by Janeth Kent Date: 20-05-2021 javascript webcam

We often use webcams to broadcast video in real time via our computer. This broadcast can be viewed, saved and even shared via the Internet. As a rule, we need software to access the webcam and stream video. But you can also stream video on websites without using third-party software.

The HTML5 method getUserMedia(), will help us to show a preview of the webcam video via Javascript. If your application needs to access the webcam to stream video, you can do it easily with HTML5 and Javascript with this tutorial. In short, we will show you how to access the webcam and capture video using HTML5 and Javascript.


getUserMedia() API


The getUserMedia() method of the MediaDevices API helps you to produce a MediaStream containing the requested media types. You can use getUserMedia to open a dialog window to request permissions from the user to use their webcam to capture an image using HTML5 and Javascript.




The following HTML code embeds a video element and draws an image on the page.

  • We will use the HTML5 <video> element to embed a video on the page.
  • We will use the <canvas> element to draw the capture of the webcam video on the page.
  • The button (snap) will execute the generation of the image capture on the video.
<!-- Stream video via webcam -->
<div class="video-wrap">
    <video id="video" playsinline autoplay></video>

<!-- Trigger canvas web API -->
<div class="controller">
    <button id="snap">Capture</button>

<!-- Webcam video snapshot -->
<canvas id="canvas" width="640" height="480"></canvas>

Javascript code


The following Javascript manages the process of streaming video through the webcam on the web page.

  • The constants define the width and height of the video.
  • The init() function initialises the getUserMedia() API.
  • The handleSuccess() function streams the webcam video into the HTML element.
  • We use the canvas API to draw the webcam capture.
'use strict';

const video = document.getElementById('video');
const canvas = document.getElementById('canvas');
const snap = document.getElementById("snap");
const errorMsgElement = document.querySelector('span#errorMsg');

const constraints = {
  audio: true,
  video: {
   width: 1280, height: 720

// Access webcam
async function init() {
  try {
   const stream = await navigator.mediaDevices.getUserMedia(constraints);
  } catch (e) {
   errorMsgElement.innerHTML = `navigator.getUserMedia error:${e.toString()}`;

// Success
function handleSuccess(stream) { = stream;
  video.srcObject = stream;

// Load init

// Draw image
var context = canvas.getContext('2d');
snap.addEventListener("click", function() {
      context.drawImage(video, 0, 0, 640, 480);
by Janeth Kent Date: 20-05-2021 javascript webcam hits : 3982  
Janeth Kent

Janeth Kent

Licenciada en Bellas Artes y programadora por pasión. Cuando tengo un rato retoco fotos, edito vídeos y diseño cosas. El resto del tiempo escribo en MA-NO WEB DESIGN AND DEVELOPMENT.


Related Posts

How to use the endsWith method in JavaScript

In this short tutorial, we are going to see what the endsWith method, introduced in JavaScript ES6, is and how it is used with strings in JavaScript. The endsWith method is…

What are javascript symbols and how can they help you?

Symbols are a new primitive value introduced by ES6. Their purpose is to provide us unique identifiers. In this article, we tell you how they work, in which way they…

Callbacks in JavaScript

Callback functions are the same old JavaScript functions. They have no special syntax, as they are simply functions that are passed as an argument to another function. The function that receives…

How to create PDF with JavaScript and jsPDF

Creating dynamic PDF files directly in the browser is possible thanks to the jsPDF JavaScript library. In the last part of this article we have prepared a practical tutorial where I…

How to make your own custom cursor for your website

When I started browsing different and original websites to learn from them, one of the first things that caught my attention was that some of them had their own cursors,…

Node.js and npm: introductory tutorial

In this tutorial we will see how to install and use both Node.js and the npm package manager. In addition, we will also create a small sample application. If you…

How to connect to MySQL with Node.js

Let's see how you can connect to a MySQL database using Node.js, the popular JavaScript runtime environment. Before we start, it is important to note that you must have Node.js installed…

JavaScript Programming Styles: Best Practices

When programming with JavaScript there are certain conventions that you should apply, especially when working in a team environment. In fact, it is common to have meetings to discuss standards…

Difference between arrow and normal functions in JavaScript

In this tutorial we are going to see how arrow functions differ from normal JavaScript functions. We will also see when you should use one and when you should use…

JavaScript Arrow functions: What they are and how to use them

In this article we are going to see what they are and how to use JavaScript Arrow Functions, a new feature introduced with the ES6 standard (ECMAScript 6). What are Arrow…

How to insert an element into an array with JavaScript

In this brief tutorial you will learn how to insert one or more elements into an array with JavaScript. For this we will use the splice function. The splice function will not…

What is the difference between primitives types and objects in JavaScript?

In this short tutorial we are going to look at the differences between primitive types and objects in JavaScript. To start with, we're going to look at what primitive types…

We use our own and third-party cookies to improve our services, compile statistical information and analyze your browsing habits. This allows us to personalize the content we offer and to show you advertisements related to your preferences. By clicking "Accept all" you agree to the storage of cookies on your device to improve website navigation, analyse traffic and assist our marketing activities. You can also select "System Cookies Only" to accept only the cookies required for the website to function, or you can select the cookies you wish to activate by clicking on "settings".

Accept All Only sistem cookies Configuration