1. A computer-implemented digital image processing method comprising: receiving pixel data representing a current image frame; calculating a bias term representing a weighting of each pixel in the current image frame towards one of a foreground bias region and a background bias region; segmenting, by a processor using an energy optimization function, the current image frame into a foreground segment and a background segment based on the pixel data and the bias term; and generating a pixel mask corresponding to pixels in at least one of the foreground segment and the background segment.