JavaScript canvas image draw

<canvas id="canvas1" width="500" height="500" style="border:1px"/>

<script>

    window.onload = function() {

        var c = document.getElementById("canvas1");

        var ctx = c.getContext("2d");

        var image = new Image();

        image.src = "./test.jpg";

        // 이미지가 로딩되면 draw

        image.onload = function() {

            image.data

            ctx.drawImage(image, 0, 0);

        }

    }

</script>