  We introduce CurveFusion, the first approach for high quality scanning of
thin structures at interactive rates using a handheld RGBD camera. Thin
filament-like structures are mathematically just 1D curves embedded in R^3, and
integration-based reconstruction works best when depth sequences (from the thin
structure parts) are fused using the object's (unknown) curve skeleton. Thus,
using the complementary but noisy color and depth channels, CurveFusion first
automatically identifies point samples on potential thin structures and groups
them into bundles, each being a group of a fixed number of aligned consecutive
frames. Then, the algorithm extracts per-bundle skeleton curves using L1 axes,
and aligns and iteratively merges the L1 segments from all the bundles to form
the final complete curve skeleton. Thus, unlike previous methods,
reconstruction happens via integration along a data-dependent fusion primitive,
i.e., the extracted curve skeleton. We extensively evaluate CurveFusion on a
range of challenging examples, different scanner and calibration settings, and
present high fidelity thin structure reconstructions previously just not
possible from raw RGBD sequences.
