Learning Spatially Collaged Fourier Bases for Implicit Neural
  Representation
Jason Chun Lok Li Chang Liu Binxiao Huang Ngai Wong
Existing approaches to Implicit Neural Representation (INR) can be
interpreted as a global scene representation via a linear combination of
Fourier bases of different frequencies. However, such universal basis functions
can limit the representation capability in local regions where a specific
component is unnecessary, resulting in unpleasant artifacts. To this end, we
introduce a learnable spatial mask that effectively dispatches distinct Fourier
bases into respective regions. This translates into collaging Fourier patches,
thus enabling an accurate representation of complex signals. Comprehensive
experiments demonstrate the superior reconstruction quality of the proposed
approach over existing baselines across various INR tasks, including image
fitting, video representation, and 3D shape representation. Our method
outperforms all other baselines, improving the image fitting PSNR by over 3dB
and 3D reconstruction to 98.81 IoU and 0.0011 Chamfer Distance.