Error in PIL, image index out of range, python

Very good, I would like you to clarify a doubt. Creating a function that from a "L" image creates a matrix with the values of its pixels, it returns this:

  

return self.im.getpixel (xy), IndexError: image index out of range

If someone can answer me, I would be very grateful, because I have hours and hours and hours with this.

The code:

from PIL import Image

def datalize(img):
    x, y = img.size
    datrix = []

    for e in xrange(x):
        datrix.append([])
            for m in xrange(y):
                delta = img.getpixel((x,y))
                delta = int(delta)
                datrix[e].append(delta)
    return datrix

Thanks in advance