How can I capture an image via the user's webcam using getUserMedia?
I want to make a program on the web which will capture an image via the user's webcam.
I am using the getUserMedia Web API. Here is my code, but it does not work. How can I change it to capture the webcam image?
<div id="container">
<video autoplay="true" id="videoElement">
</video>
</div>
<script>
</script>
There is the JS:
var video = document.querySelector("#videoElement");
navigator.getUserMedia, elem = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia || navigator.oGetUserMedia;
console.log(navigator.getUserMedia);
if (navigator.getUserMedia) {
navigator.getUserMedia({video: true}, handleVideo, videoError);
}
function handleVideo(stream) {
video.src = window.URL.createObjectURL(stream);
}
function videoError(e) {
// do something
}
Answer
You can use this working sample
<!DOCTYPE html>
<html>
<head>
</head>
<body onload="init();">
<h1>Take a snapshot of the current video stream</h1>
Click on the Start WebCam button.
<p>
<button onclick="startWebcam();">Start WebCam</button>
<button onclick="stopWebcam();">Stop WebCam</button>
<button onclick="snapshot();">Take Snapshot</button>
</p>
<video onclick="snapshot(this);" width=400 height=400 id="video" controls autoplay></video>
<p>
Screenshots : <p>
<canvas id="myCanvas" width="400" height="350"></canvas>
</body>
<script>
//--------------------
// GET USER MEDIA CODE
//--------------------
navigator.getUserMedia = ( navigator.getUserMedia ||
navigator.webkitGetUserMedia ||
navigator.mozGetUserMedia ||
navigator.msGetUserMedia);
var video;
var webcamStream;
function startWebcam() {
if (navigator.getUserMedia) {
navigator.getUserMedia (
// constraints
{
video: true,
audio: false
},
// successCallback
function(localMediaStream) {
video = document.querySelector('video');
video.src = window.URL.createObjectURL(localMediaStream);
webcamStream = localMediaStream;
},
// errorCallback
function(err) {
console.log("The following error occured: " + err);
}
);
} else {
console.log("getUserMedia not supported");
}
}
function stopWebcam() {
webcamStream.stop();
}
//---------------------
// TAKE A SNAPSHOT CODE
//---------------------
var canvas, ctx;
function init() {
// Get the canvas and obtain a context for
// drawing in it
canvas = document.getElementById("myCanvas");
ctx = canvas.getContext('2d');
}
function snapshot() {
// Draws current image from the video element into the canvas
ctx.drawImage(video, 0,0, canvas.width, canvas.height);
}
</script>
</html>