How to open webcam using JavaScript?
In this tutorial, we will look at the process of opening a webcam using JavaScript. So, this can be done using WebRTC. WebRTC is the abbreviation for Web Real-Time Communications. Using this object we can access and capture the webcam and microphone devices available in the user's device.
How to access the webcam?
We can access the user device webcam and microphone using the ECMAScript object navigator.mediaDevices.getUserMedia(constraints).
Therefore, the getUserMedia() function will by default seek the user's permission to use your webcam. The function returns a promise, once you click OK and grant permission, then the promise will be fired and it will enable the webcam in your system; otherwise, if you don't allow it, Well it also has a catch method to turn off the webcam.
We can also pass parameters to the function getUserMedia() function, just like we want an image of a specific width or height.
The process of opening the webcam
We can follow the steps below to open the webcam using JavaScript.
Step 1 - Add HTML elements such as video and button.
Step 2 - Check if the webcam is available and resolve the returned promise getUserMedia function.
STEP 3 - Pass parameters to getUserMedia() function such as audio and video true because we will use them
Step 4 - For smartphones we have to use faceingMode option for both The camera is available and by default we turn it on with the front camera.
Example
Below is a simple program to open a webcam. We followed the above steps to complete our task.
<html>
<head>
<title>Open webcam using JavaScript. </title>
</head>
<body>
<h1>Open WebCam Using JavaScript</h1>
<br/>
<button id="startBtn" onclick="openCam()">Open Webcam</button>
<br/><br/>
<video id="videoCam"></video>
<script>
function openCam(){
let All_mediaDevices=navigator.mediaDevices
if (!All_mediaDevices || !All_mediaDevices.getUserMedia) {
console.log("getUserMedia() not supported.");
return;
}
All_mediaDevices.getUserMedia({
audio: true,
video: true
})
.then(function(vidStream) {
var video = document.getElementById('videoCam');
if ("srcObject" in video) {
video.srcObject = vidStream;
} else {
video.src = window.URL.createObjectURL(vidStream);
}
video.onloadedmetadata = function(e) {
video.play();
};
})
.catch(function(e) {
console.log(e.name + ": " + e.message);
});
}
</script>
</body>
</html>
Use CSS to design the interface
First, let's design our web interface using HTML and CSS.
We add a component like the webcam video area and use CSS to set its height and width to 400px and the background color to black. It will display the webcam video stream.
Add a button named Open Camera and apply its CSS properties; this button will be used to launch the webcam.
Now we will add the function code and embed it into the main program.
We will call this function when the OpenCamera button is clicked, and within this function, all instructions will happen as discussed above.
Example
In the example below, we added some CSS to design a more interactive interface.
<html>
<head>
<title>Open webcam using JavaScript.</title>
<style>
*{
background-color: #658EA9;
}
#videoCam {
width: 630px;
height: 300px;
margin-left: 0px;
border: 3px solid #ccc;
background: black;
}
#startBtn {
margin-left: 280px;
width: 120px;
height: 45px;
cursor: pointer;
font-weight: bold;
}
#startBtn:hover{
background-color: #647C90;
color: red;
}
</style>
</head>
<body>
<h1>Open WebCam Using JavaScript</h1>
<br/>
<video id="videoCam"></video>
<br/><br/>
<button id="startBtn" onclick="openCam()">Open Camera</button>
<script>
function openCam(){
let All_mediaDevices=navigator.mediaDevices
if (!All_mediaDevices || !All_mediaDevices.getUserMedia) {
console.log("getUserMedia() not supported.");
return;
}
All_mediaDevices.getUserMedia({
audio: true,
video: true
})
.then(function(vidStream) {
var video = document.getElementById('videoCam');
if ("srcObject" in video) {
video.srcObject = vidStream;
} else {
video.src = window.URL.createObjectURL(vidStream);
}
video.onloadedmetadata = function(e) {
video.play();
};
})
.catch(function(e) {
console.log(e.name + ": " + e.message);
});
}
</script>
</body>
</html>
As you can observe from the output screen, when we click on the "Open Camera" button, it asks for access to the webcam and when we allow that access, it launches the webcam in the video area screen Video streaming; if we don't grant access, it won't show any output.
The above is the detailed content of How to open webcam using JavaScript?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
Replace String Characters in JavaScript
Mar 11, 2025 am 12:07 AM
Detailed explanation of JavaScript string replacement method and FAQ This article will explore two ways to replace string characters in JavaScript: internal JavaScript code and internal HTML for web pages. Replace string inside JavaScript code The most direct way is to use the replace() method: str = str.replace("find","replace"); This method replaces only the first match. To replace all matches, use a regular expression and add the global flag g: str = str.replace(/fi
Custom Google Search API Setup Tutorial
Mar 04, 2025 am 01:06 AM
This tutorial shows you how to integrate a custom Google Search API into your blog or website, offering a more refined search experience than standard WordPress theme search functions. It's surprisingly easy! You'll be able to restrict searches to y
Build Your Own AJAX Web Applications
Mar 09, 2025 am 12:11 AM
So here you are, ready to learn all about this thing called AJAX. But, what exactly is it? The term AJAX refers to a loose grouping of technologies that are used to create dynamic, interactive web content. The term AJAX, originally coined by Jesse J
Example Colors JSON File
Mar 03, 2025 am 12:35 AM
This article series was rewritten in mid 2017 with up-to-date information and fresh examples. In this JSON example, we will look at how we can store simple values in a file using JSON format. Using the key-value pair notation, we can store any kind
8 Stunning jQuery Page Layout Plugins
Mar 06, 2025 am 12:48 AM
Leverage jQuery for Effortless Web Page Layouts: 8 Essential Plugins jQuery simplifies web page layout significantly. This article highlights eight powerful jQuery plugins that streamline the process, particularly useful for manual website creation
What is 'this' in JavaScript?
Mar 04, 2025 am 01:15 AM
Core points This in JavaScript usually refers to an object that "owns" the method, but it depends on how the function is called. When there is no current object, this refers to the global object. In a web browser, it is represented by window. When calling a function, this maintains the global object; but when calling an object constructor or any of its methods, this refers to an instance of the object. You can change the context of this using methods such as call(), apply(), and bind(). These methods call the function using the given this value and parameters. JavaScript is an excellent programming language. A few years ago, this sentence was
Improve Your jQuery Knowledge with the Source Viewer
Mar 05, 2025 am 12:54 AM
jQuery is a great JavaScript framework. However, as with any library, sometimes it’s necessary to get under the hood to discover what’s going on. Perhaps it’s because you’re tracing a bug or are just curious about how jQuery achieves a particular UI
10 Mobile Cheat Sheets for Mobile Development
Mar 05, 2025 am 12:43 AM
This post compiles helpful cheat sheets, reference guides, quick recipes, and code snippets for Android, Blackberry, and iPhone app development. No developer should be without them! Touch Gesture Reference Guide (PDF) A valuable resource for desig
