How to let User crop their uploaded picture

[Flixmix]

Hey you

I hope you can help me...I searched two days in all possible topics, but didn't get my answer.

I have to built up a shop for a friend and I'm testing everything on my domain. I found out how customers can upload a required picture to their order. But after that I want them to crop their uploaded picture to a predefined ratio. Then the cropped picture will be saved with the order in the cart.

The Javascript could be: http://www.defusion.org.uk/code/javascript-image-cropper-ui-using-prototype-scriptaculous/

The window for cropping could use this: http://orangoo.com/labs/greybox/examples.html

Here the steps again:

1. User searchs for his picture at the product.
2. After uploaded, a window opens where user must crop image.
3. The cropped image will be attached to the order.

Thank you in advance

Flixmix