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Drawing a rectangle in canvas

I can draw a rectangle over the video in canvas. But he is hiding behind the video, but they manage to see it through the side. Pls suggests what I have to do to draw over the video, just as I can draw on top of the image. Code I using:

   <p>Video to use:</p>
<video id="video1" controls width="270" autoplay>
  <source src="http://www.craftymind.com/factory/html5video/BigBuckBunny_640x360.ogv" type="video/ogg"/> 
</video>

<p>Canvas (the code draws the current frame of the video every 20 millisecond):</p>
<canvas id="myCanvas" width="270" height="135" style="border:1px solid #d3d3d3;">
Your browser does not support the HTML5 canvas tag.</canvas>

></canvas></div>

Check out my jsfiddle at: http://jsfiddle.net/mummydaddy/LjqbuLne/

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2 answers

You need to do it like this:

Fiddle

var v = document.getElementById("video1");
var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
var i;

function draw() {
    i = window.setInterval(function draw() {
        ctx.drawImage(v, 5, 5, 260, 125);
        ctx.clearRect(135, 92, 126, 34);
        ctx.beginPath();
        ctx.rect(135, 92, 126, 34);
        ctx.fillStyle = 'yellow';
        ctx.fill();
        ctx.lineWidth = 7;
        ctx.strokeStyle = 'black';
        ctx.stroke();
    }, 20);
}

draw();
v.addEventListener("play", function () {
    draw();
}, false);
v.addEventListener("pause", function () {
    clearInterval(i);
}, false);
v.addEventListener("ended", function () {
    clearInterval(i);
}, false);
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source

To see your video under your rectangle, you need to draw your rectangle in all frames, for example:

v.addEventListener("play", function() {var i = window.setInterval(function() {

  ctx.clearRect ( 0 , 0 , 300 , 300 );    // clear your canvas if you move shapes
  ctx.drawImage(v,5,5,260,125) 
  ctx.beginPath();
  ctx.rect(100, 100, 200, 200);
  ctx.fillStyle = 'yellow';
  ctx.fill();
  ctx.lineWidth = 7;
  ctx.strokeStyle = 'black';
  ctx.stroke();
},20); }, false);

, ctx, context var. node, ... .

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