Henry Segerman
This is the equirectangular, "unwrapped" version of a spherical
video. It can also be seen in the "in-sphere" view on YouTube. Using
Möbius transformations applied to the Riemann sphere, one can
produce a zoom-like effect. Zooming is used in flat media to make
"Droste effect" images: images that contain a smaller copy of
themselves. In this spherical video we do the same, adding the extra
feature that the zoomed copies of each frame are offset in time. We
slowly zoom from one copy of the scene into the "smaller" copy. The
duration of the time offset matches the flight time of the camera;
thus the video loops. For more details on the effect used in this
video, see "Squares that Look Round: Transforming Spherical Images",
by Saul Schleimer and Henry Segerman,
http://arxiv.org/abs/1605.01396