backdrop of boot menu (using emcore on 7th gen classic ipod)

[Frankenpod]

Just asking out of curiosity, not really a problem.

I notice that my different 7th gen rockboxed ipods have different backdrops on the initial menu for chosing rockbox vs console vs shutting down etc.  I'm not sure if this is part of emcore or rockbox.  Some have the swirly blue pattern that seems usual for rockbox, one has an animated snow scene.

Just wondering, is this due to using different versions of rockbox or different versions of emcore? [I quite like the snow scene, just not sure how I came to have it there!]