I was playing with wallpaper effects and came across a strange phenomenon. If you take a 640x960 image and blacken every even row, the iPhone can't display the colors in the image. If you delete every odd row, the image displays fine. Here are two wallpapers you can try to prove this for yourself. (Source here: http://commons.wikimedia.org/wiki/File:Eta_Carinae_Nebula_1.jpg ) What do you make of this rather trivial issue?