Honestly, I have no idea I'm still pretty new to SFML myself. Does it happen with all images or just the one?
Edit: Your doing a lot in the while loop including loading the image, try moving that out of the loop.
@ Script Coder: Do yourself a HUGE favor and don't do that. Just jump right into SFML 2.0. I am used to 1.6, I'd confidently say that I know it well but now that I am moving to 2.0 things have changed quite a bit. Both major things like how you are meant to handle events and minor things like the capitalization in the function names. It's getting really annoying having to keep going back to the tutorial for something that I can tell you off the top of my head how to do in 1.6.