<!doctype html>
<canvas id="canvas" height="200" width="200"></canvas>
<div id="new"></div>
<script>
var div = document.getElementById("new");
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var img = new Image();
img.src = 'http://www.w3.org/html/logo/downloads/HTML5_Logo_512.png';
//img.src = 'local.png';
img.onload = function(){
//draws the image on the canvas (works)
ctx.drawImage(img,0,0,200,200);
//creates an image from the canvas (works only for local.png)
var sourceStr = canvas.toDataURL();
//creates the img-tag and adds it to the div-container
var newImage = document.createElement("img");
newImage.src = sourceStr;
div.appendChild(newImage);
}
</script>
This script creates a canvas with the html5-logo. From this canvas I want to create an image, using the "toDataURL()"-method. Here I get a security error.
Firefox says - Error: uncaught exception: [Exception... "Security error" code: "1000" nsresult: "0x805303e8 (NS_ERROR_DOM_SECURITY_ERR)"
Chrome says - Uncaught Error: SECURITY_ERR: DOM Exception 18
If I use the script with an image on the server it works fine. So it think this time it is really a feature and not a bug.
Does anyone has an idea how I can create an image using canvas with out of an image form an other server?
BTW: the error occurs if you run the site as a local file without a webserver.
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