gistfile1.txt

ngular.module('Fn')
    .factory('ImageService', function () {
        return {
            calculateOffset: function(width, height) {
                if (width === height) {
                    return false;
                }
                var bigger, smaller, side;

                var style = {};

                if(width > height) {
                    bigger = width;
                    smaller = height;
                    side = 'top';
                } else {
                    bigger = height;
                    smaller = width;
                    side = 'left';
                }

                style[side] = (((bigger - smaller) / bigger) * 50) + '%';

                return style;
            }        
        };
});