  Image relighting is attracting increasing interest due to its various
applications. From a research perspective, image relighting can be exploited to
conduct both image normalization for domain adaptation, and also for data
augmentation. It also has multiple direct uses for photo montage and aesthetic
enhancement. In this paper, we review the NTIRE 2021 depth guided image
relighting challenge.
  We rely on the VIDIT dataset for each of our two challenge tracks, including
depth information. The first track is on one-to-one relighting where the goal
is to transform the illumination setup of an input image (color temperature and
light source position) to the target illumination setup. In the second track,
the any-to-any relighting challenge, the objective is to transform the
illumination settings of the input image to match those of another guide image,
similar to style transfer. In both tracks, participants were given depth
information about the captured scenes. We had nearly 250 registered
participants, leading to 18 confirmed team submissions in the final competition
stage. The competitions, methods, and final results are presented in this
paper.
