Image cut top-bottom

[razvanphp]

Hey, thanks again for this great script.

I've found a small bug, when the image is is not square, the distorsion goes outside of the canvas size, cutting a little bit from the top and bottom.

Here's a screenshot:

[ericleong]

I think the best solution to this is to expose a method that returns the dimensions of the distorted image, that way the desired canvas can be provided to the library. I'll look into this.