JS Canvas Webam With Random BG Color

<body onload="Gen()">
<video id="video" autoplay hidden>
</video>
<canvas id="canvas" width="500" height="500" style="border:0px solid"/>

<script>

var video = document.getElementById("video");
var c = document.getElementById("canvas");
var ctx = c.getContext("2d");
var i=0;
var canvas = document.getElementById('canvas');
var context = canvas.getContext('2d');
var video = document.getElementById('video');
var mediaConfig = {video:true,audio:true};
navigator.mediaDevices.getUserMedia(mediaConfig).then(function(stream) {
video.src = this.window.URL.createObjectURL(stream);
video.play();
  video.addEventListener("play", function() {i = window.setInterval(function() {
ctx.drawImage(video,0,0,500,500)},1);

}, false);
});
  function Gen()
{
var text = "";
var possible = "FABCGDEG01234567";
for(var i=0; i!=6; i++)
text+=possible.charAt(Math.floor(Math.random()*possible.length));
document.body.style.backgroundColor=(text);

}
</script>