The primal sketch is a fundamental representation in Marr's vision theory,
which allows for parsimonious image-level processing from 2D to 2.5D
perception. This paper takes a further step by computing 3D primal sketch of
wireframes from a set of images with known camera poses, in which we take the
2D wireframes in multi-view images as the basis to compute 3D wireframes in a
volumetric rendering formulation. In our method, we first propose a NEural
Attraction (NEAT) Fields that parameterizes the 3D line segments with
coordinate Multi-Layer Perceptrons (MLPs), enabling us to learn the 3D line
segments from 2D observation without incurring any explicit feature
correspondences across views. We then present a novel Global Junction
Perceiving (GJP) module to perceive meaningful 3D junctions from the NEAT
Fields of 3D line segments by optimizing a randomly initialized
high-dimensional latent array and a lightweight decoding MLP. Benefitting from
our explicit modeling of 3D junctions, we finally compute the primal sketch of
3D wireframes by attracting the queried 3D line segments to the 3D junctions,
significantly simplifying the computation paradigm of 3D wireframe parsing. In
experiments, we evaluate our approach on the DTU and BlendedMVS datasets with
promising performance obtained. As far as we know, our method is the first
approach to achieve high-fidelity 3D wireframe parsing without requiring
explicit matching.Comment: Technical report; Video can be found at https://youtu.be/qtBQYbOpVp