Is it possible to getImageData on Firefox without enabling Cors?

I’d like to do this simple task of taking a local file and checking its RGB value. But Firefox’s security makes it difficult… First, getImageData gives an insecure warning, to get around it, I set crossOrigin as “anonymous”, however, this results in “Cross-Origin Request Blocked”.

var ctx = document.getElementById("canvas").getContext("2d");
var img = new Image();
img.crossOrigin = "anonymous";

img.onload = function() {
     var d = ctx.getImageData(0, 0, 1, 1).data;

}
img.src = 'picture.jpeg';

I realize that I could around this by enabling Cors or doing a localhost, but I prefer neither. Are there are any other choices?