javascript - SecurityError: The operation is insecure. using Htmlcanvas -

trying convert images drag , place on canvas element png or jpeg photo (sort of moodboard concept polyvore) can view images place on canvas @ once in 1 png or jpeg photo. can save or whatever photo.

but run securityerror: operation insecure. when press save , try convert data show saved image myself using .alert() method. ideas how can past error accomplish goal? thank you!

here link project view live: http://amechi101.github.io/moodboard/

html:

 <div id="container" ondrop="drop(event)" ondragover="allowdrop(event)"></div>  <div class="buttonmoodboard">     <button class="btn btn-primary btn-lg" id="save">save moodboard</button>   </div> 

javascript:

var stage = new kinetic.stage({                 container: 'container',                 width: 500,                 height:500             });              var layer = new kinetic.layer();  uni_width = 120;  function allowdrop(ev) {     ev.preventdefault(); }  function drag(ev) {     ev.datatransfer.setdata("text", ev.target.id); }  function drop(ev) {     ev.preventdefault();     data = ev.datatransfer.getdata("text");     img_received = document.getelementbyid(data);     ratio = img_received.height / img_received.width;      var c=document.getelementbyid("container");     drop_x=ev.pagex-c.offsetleft;     drop_y=ev.pagey-c.offsettop;      var imageobj = new image();     imageobj.src = img_received.src;     imageobj.onload = function() {         var new_image = new kinetic.image({         x: drop_x - uni_width / 2,         y: drop_y - uni_width * ratio / 2,         image: imageobj,         width: uni_width,         height: uni_width * ratio,         draggable: true         });      // add shape layer     layer.add(new_image);      // add layer stage     stage.add(layer);   }; }  //saving data base via json document.getelementbyid('save').addeventlistener('click', function (canvas) {         var json = stage.tojson();        var canvas = document.getelementsbytagname("canvas");     var img    = canvas[0].todataurl("image/png");      var alertjson = alert(img);     console.log(json, alertjson);    }, false); 

to request image using cors can either specify usage in image tag:

<img src="..." crossorigin="anonymous"> 

or using javascript:

var img = new image;  img.onload = loaded;            // load handler img.crossorigin = 'anonymous'; img.src = '...'; 

a request no guarantee - server support cors or not. if doesn't need move image same server (origin) page or server support cors.