full-page-camera-with-audio.js

'use strict';

(async () => {
  const stream = await navigator.mediaDevices.getUserMedia({ video: true, audio: true });
  const vid = document.createElement('video');
  vid.srcObject = stream;
  document.body.appendChild(vid);
  vid.style.position = 'absolute';
  vid.style.left = '0px';
  vid.style.top = '0px';
  vid.style.width = '100vw';
  vid.style.height = '100vh';
  vid.style.objectFit = 'cover';
  vid.style.transform = 'scaleX(-1)';
  await vid.play();
})()
  .catch(err => console.error(err))
;