javascript - Cross-origin data in HTML5 canvas -


i'm loading image in js , draw canvas. after drawing, retrieve imagedata canvas:

var img = new image(); img.onload = function() {     canvas.drawimage(img, 0, 0);     originalimagedata = canvas.getimagedata(0,0,width, height)); //chrome fails } img.src = 'picture.jpeg';

this works both in safari , firefox, fails in chrome following message:

unable image data canvas because canvas has been tainted cross-origin data.

the javascript file , image located in same directory, don't understand behavior of chorme.

to enable cors (cross-origin resource sharing) images pass http header image response:

access-control-allow-origin: *

the origin determined domain , protocol (e.g. http , https not same) of webpage , not location of script.

if running locally using file:// seen cross domain issue; better go via

http://localhost/

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