I want to use the height of the image outside the onload function. I tried this, but it's not working

                var nr;
                function getHeightOfImage(src, cb) {
                var img = document.createElement('img');
                img.onload = function () {
                    cb(this.height);
                };
                img.src = src;
            }


            getHeightOfImage(vid.Image, function (height) {
                console.log("height", height); //height available
                nr = height; // nr setted here
            });


            console.log("nr", nr); //nr - is not setted here