split an image into sectors

[iwanttolearnc]

im quite new to python so forgive my stupidity. ive downloaded numpy and here are a few things i understand regarding images and numpy

1.images are made up of pixels that have coordinates, a 2d array i believe
2.numpy has the ability to handle arrays and split them

what i want to do is this: given a 300x300 image i would like to split it into smaller 5x5 arrays.

ive tried numpy.split and have seen it work for 1 dimensional arrays. the problem is how do i make it work for 2d arrays

im=Image.open ("trial.jpg")              

im.thumbnail((300,300) , Image.ANTIALIAS)   
im.save("im.jpg")

openres = Image.open ("im.jpg")
loadres = openres.load()

b = numpy.split(loadres,100)

when i run the code above i get a lot of errors. anyone care to help?

[slate]

http://effbot.org/zone/pil-changes-116.htm

import numpy, Image
i = Image.open('lena.jpg')
a = numpy.asarray(i) # a is readonly
i = Image.fromarray(a)

[iwanttolearnc]

thanks