You can use HTML5 for this:
<video autoplay></video>
<script>
var onFailSoHard = function(e) {
console.log('Reeeejected!', e);
};
// Not showing vendor prefixes.
navigator.getUserMedia({video: true, audio: true}, function(localMediaStream) {
var video = document.querySelector('video');
video.src = window.URL.createObjectURL(localMediaStream);
// Note: onloadedmetadata doesn't fire in Chrome when using it with getUserMedia.
// See crbug.com/110938.
video.onloadedmetadata = function(e) {
// Ready to go. Do some stuff.
};
}, onFailSoHard);
</script>