  Addressing the intricate challenge of modeling and re-rendering dynamic
scenes, most recent approaches have sought to simplify these complexities using
plane-based explicit representations, overcoming the slow training time issues
associated with methods like Neural Radiance Fields (NeRF) and implicit
representations. However, the straightforward decomposition of 4D dynamic
scenes into multiple 2D plane-based representations proves insufficient for
re-rendering high-fidelity scenes with complex motions. In response, we present
a novel direction-aware representation (DaRe) approach that captures scene
dynamics from six different directions. This learned representation undergoes
an inverse dual-tree complex wavelet transformation (DTCWT) to recover
plane-based information. DaReNeRF computes features for each space-time point
by fusing vectors from these recovered planes. Combining DaReNeRF with a tiny
MLP for color regression and leveraging volume rendering in training yield
state-of-the-art performance in novel view synthesis for complex dynamic
scenes. Notably, to address redundancy introduced by the six real and six
imaginary direction-aware wavelet coefficients, we introduce a trainable
masking approach, mitigating storage issues without significant performance
decline. Moreover, DaReNeRF maintains a 2x reduction in training time compared
to prior art while delivering superior performance.
