<p>要使用的图片:</p>

<img id="scream" src="/static/i/img3.jpg" width="500">

<p>画布:</p>

<canvas id="canvas-1" width="300" height="150" style="border:1px solid #d3d3d3;background:#ffffff;">你的浏览器不支持 canvas 元素</canvas>

<script>

var img1 = document.createElement("img");

img1.src="/static/i/img3.jpg";

img1.onload= function() {

    var c=document.getElementById("canvas-1");

    var canvOK=1;

    try {c.getContext("2d");}

    catch (er) {canvOK=0;}

    if (canvOK==1)

    {

        var ctx=c.getContext("2d");

        var img= this

        ctx.drawImage(img,10,10);

    }