 Human dancers were referenced for animating the dance movements of the chipmunks, and YouTube videos of famous guitarists playing the guitar influenced how Alvin's guitar-playing was animated.High-dynamic-range images of sets were also used for lighting the chipmunks to fit the live-action shots.The most difficult part of integrating the CGI critters in the live-action shots was match moving for instances when they climb on Seville's head.