watermark.js - скрипт наложения watermark на стороне клиента
Пример кода
// load local images
watermark(['/img/coffee.jpg', '/img/logo.png']);
// load cross domain images
watermark(['http://web.com/a.jpg', 'http://web.com/b.jpg'], function (img) {
img.crossOrigin = 'anonymous';
});
// load a url and a file object
var upload = document.querySelector('input[type=file]').files[0];
watermark(['/img/photo.jpg', upload]);