JS Canvas Webcam Custom Fade Out Example SRC V3

<center>
<body bgcolor="black">
<video id="video" autoplay hidden>
</video>
<canvas id="canvas" width="500" height="500"style="opacity:1.0;fillColor:black;">
<script>
var ii=1;
var inn=prompt("Enter A # Between 0.1 And 0.0001:");
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:false};
navigator.mediaDevices.getUserMedia(mediaConfig).then(function(stream) {
video.src = this.window.URL.createObjectURL(stream);
video.play();
video.addEventListener("play", function() {i = window.setInterval(function() {
canvas.style.opacity-=inn;
canvas.style.color='red'
ctx.drawImage(video,ii,23,500,777)},25);
}, false);
});
</script>