1. A computer-implemented method for generating a background image that is displayed while foreground images are being scrolled, comprising: in response to a first plurality of foreground images being displayed, selecting a first foreground image from the first plurality of foreground images; generating a first background image based on the first foreground image; displaying a first portion of the first background image; displaying a remaining portion of the first background image with an alpha ramp that transitions the remaining portion of the first background image from opaque to transparent; receiving user input causing foreground images to be scrolled such that the first plurality of foreground images is no longer displayed and a second plurality of foreground images is displayed; in response to the second plurality of foreground images being displayed, selecting a second foreground image from the second plurality of foreground images; generating a second background image based on the second foreground image; displaying a cross-fading animation that transitions from the remaining portion of the first background image to which the alpha ramp was added to a first portion of the second background image; and displaying the first portion of the second background image.