image_check.py

#!/usr/bin/python3
import kivy
kivy.require("1.9.0")

from kivy.app import App
from kivy.uix.widget import Widget
from kivy.uix.image import Image
from kivy.graphics import Rectangle
from kivy.clock import Clock
from kivy.properties import ObjectProperty

class Main(Widget):
    foreground = ObjectProperty(None)
    background = ObjectProperty(None)

    def setup(self):
        with self.canvas:
            Rectangle(texture=self.background.texture, pos=[200,200], size_hint_x=None, size_hint_y=None, size=[800, 800])
            Rectangle(texture=self.foreground.texture, pos=[200,200], size_hint_x=None, size_hint_y=None, size=[800, 800])

    def update(self, dt):
        pass

class ImageCheckApp(App):
    def build(self):
        game = Main()
        game.setup()
        Clock.schedule_interval(game.update, 1/60)
        return game

if __name__ == "__main__":
    app = ImageCheckApp()
    app.run()

imagecheck.kv

#: kivy 1.9.1

<Main>:
    foreground: fg
    background: bg
    IMG:
        id: fg
        source: "background.png"
    IMG:
        id: bg
        source: "foreground.png"

<IMG@Image>:
    allow_stretch: True
    keep_ratio: True
    size_hint_x: None
    size_hint_y: None