  3D understanding and rendering of moving humans from monocular videos is a
challenging task. Despite recent progress, the task remains difficult in
real-world scenarios, where obstacles may block the camera view and cause
partial occlusions in the captured videos. Existing methods cannot handle such
defects due to two reasons. First, the standard rendering strategy relies on
point-point mapping, which could lead to dramatic disparities between the
visible and occluded areas of the body. Second, the naive direct regression
approach does not consider any feasibility criteria (ie, prior information) for
rendering under occlusions. To tackle the above drawbacks, we present OccNeRF,
a neural rendering method that achieves better rendering of humans in severely
occluded scenes. As direct solutions to the two drawbacks, we propose
surface-based rendering by integrating geometry and visibility priors. We
validate our method on both simulated and real-world occlusions and demonstrate
our method's superiority.
