html2canvas(document.querySelector('#index'),{
dpi: window.devicePixelRatio * 2
}).then(function(canvas) {
document.querySelector(".canvas").setAttribute('src',canvas.toDataURL());
$("#index").hide();
$(".canvas").show();
});
<img class="canvas" src="" >
<div class="award_img" id="index"></div>
// js引入代码
<script type="text/javascript" src="https://blog-static.cnblogs.com/files/gongxiaoyan/jquery-3.4.1.min.js"></script>
<script type="text/javascript" src="https://blog-static.cnblogs.com/files/gongxiaoyan/html2canvas.js"></script>