批量添加水印

watermark.js leverages canvas pooling so canvases are reused when possible

/**
* Place a watermark
*/
function placeMark(i) {
watermark(['img/shepherd.jpg', 'img/logo.png'])
  .image(watermark.image.lowerRight())
  .then(function (img) {
    var container = document.getElementById('image-' + (i + 1));
    container.appendChild(img);
  });
}

/**
* Queue up a bunch of async watermark operations
*/
for(var i = 0; i < 9; i++) {
 setTimeout((function(index) {
   return function() {
     placeMark(index);
   };
 })(i), 10);
}