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Raphael.js jump with a scale causes strange jump behavior

I'm trying to resize / scale the image using the Raphael.js method built into the drag and drop method, but I get some weird behavior.

Here is jsfiddle: http://jsfiddle.net/charleshimmer/5pdyy/1/

Use the right or lower right corner to resize the image. You will see some strange behavior when it jumps and skips using the scale method. Can anyone understand why?

I can make it change the smoothing size by updating the width and height of the image, but then the aspect ratio is disabled. Using image.scale, the aspect ratio is maintained, but then it jumps around the place.

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HTML

<html>
 <head>
    <title>Photo Test</title>
 </head>
 <body>
    <div id="editor"></div>
    <img id="image" 
         src="http://www.pyrblu.com/assets/launchpad_resources/demo.jpg"
         style="display:none"
    >
 </body>
</html>

CSS

svg 
  {
  border: 1px solid red;
  background:#fff;
  border-radius: 45px;
  }

Javascript

var Editor = {},
ctFactor = 7;

// create Raphael canvas
Editor.paper = Raphael('editor', 582, 514.8);

// wait for image to load
$("#image").load(function(){

    Editor.image = Editor.paper.image("http://www.pyrblu.com/assets/launchpad_resources/demo.jpg", 25, 25, 282, 465.2);

    Editor.image.drag(Editor.dragging, Editor.dragStart, Editor.dragEnd);
    Editor.image.ready = true;
    Editor.image.mousemove(function (e) {
        // only do this if the user isn't currently moving / resizing image
        if( ! this.ready){
            return;
        }
        var side = Editor.sideDection(e, this);
        // if the user mouse is along the edge we want resize
        if(side){
            Editor.image.state = 'resizable';
        }
        // else it towards the middle and we want to move
        else{
            Editor.image.state = 'movable';
        }
        var cursor = (side) ? side + '-resize' : 'move';
        this.attr('cursor', cursor);
    });

});

Editor.sideDection = function(event, ct){
    // check north side
    var directions = {
        n: Math.abs(event.offsetY - ct.attr('y')) <= ctFactor,
        s: Math.abs(event.offsetY - (ct.attr('height') + ct.attr('y'))) <= ctFactor,
        e: Math.abs(event.offsetX - (ct.attr('width') + ct.attr('x'))) <= ctFactor,
        w: Math.abs(event.offsetX - ct.attr('x')) <= ctFactor
    },
    side = '';

    // loop through all 4 sides and concate the ones that are true
    for(var key in directions) {
        if(directions.hasOwnProperty(key)){
            if(directions[key]){
                side = side + key;
            }    
        }
    }

    return side;
};

Editor.dragStart = function () {
    console.log('at start');
    // grab original x, y coords        
    this.ox = this.attr("x");
    this.oy = this.attr("y");

    // toggle user is doing something
    // so other actions are blocked
    this.ready = false;

    this.animate({opacity: .65}, 500, ">");
};

Editor.dragging = function (dx, dy, x, y, e) {
    console.log('at dragging');
    if(this.state === 'movable'){
        // this does the actual moving of the object
        this.attr({x: this.ox + dx, y: this.oy + dy});    
    }
    // we are resizing then
    else{

        var diff = (x - this.ox) - this.attr('width'),
            xratio = 1 + diff / this.attr('width'),
            yratio = 1 + diff / this.attr('height');

        console.log('diff: ', diff, 'xratio: ', xratio, 'yratio: ', yratio);           
        //resize image, update both height and width to keep aspect ratio
        // this.attr({
        //     'width': this.attr('width') * xratio,
        //     'height': this.attr('height') * yratio
        // });
        this.scale(xratio, xratio, 0, 0);

        //console.log('h: ', this.attr('height'), 'w: ', this.attr('width'), 'r', this.attr('width') / this.attr('height'));
    }
};

Editor.dragEnd = function () {
    this.ready = true;
    this.animate({opacity: 1}, 500, ">");
};
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