https://larsjung.de/jquery-qrcode/
<!DOCTYPE html>
<html>
<head>
<title>js-二维码</title>
</head>
<body>
<div id="qrCode"></div>
<img id="logo" style="display: none;" src="logo.jpg" />
<script type="text/javascript" src="jquery-2.2.0.min.js"></script>
<script type="text/javascript" src="jquery.qrcode.min.js"></script>
<script type="text/javascript">
window.onload = function () {
$("#qrCode").qrcode({
render: ‘canvas‘,
ecLevel: ‘H‘,
text: ‘http://www.youfeidao.com‘,
size: 300,
mode: 4,
mSize: 0.12,
image: $(‘#logo‘)[0],
quiet: 0
});
}
</script>
</body>
</html>
原文：http://www.cnblogs.com/hnlong1/p/5241080.html