Image content retrieve

[s_jmp]

I want to retrieve a variable's data that contain's an image
i am using pys60 ,for example i have created a class of Image like this:
i=Image.new((size,size))
and drawn a rectangle in it:
i.rectangle('proper values')
now there is a rectangle in i
so we have an image and something is handling the data that shows the rectangle
i want to get the data that represent the rectangle just like how we retrieve a jpeg file content and analyse it
but i have no idea on how to do it
any idea's?