Papers › Hi-LASSIE: High-Fidelity Articulated Shape and Skeleton Discovery from Sparse Image Ensemble

Hi-LASSIE: High-Fidelity Articulated Shape and Skeleton Discovery from Sparse Image Ensemble

21 Dec 2022CVPR 2023 1arXiv:2212.11042archive 2025-07-28

Chun-Han Yao, Wei-Chih Hung, Yuanzhen Li, Michael Rubinstein, Ming-Hsuan Yang, Varun Jampani

Automatically estimating 3D skeleton, shape, camera viewpoints, and part articulation from sparse in-the-wild image ensembles is a severely under-constrained and challenging problem. Most prior methods rely on large-scale image datasets, dense temporal correspondence, or human annotations like camera pose, 2D keypoints, and shape templates. We propose Hi-LASSIE, which performs 3D articulated reconstruction from only 20-30 online images in the wild without any user-defined shape or skeleton templates. We follow the recent work of LASSIE that tackles a similar problem setting and make two significant advances. First, instead of relying on a manually annotated 3D skeleton, we automatically estimate a class-specific skeleton from the selected reference image. Second, we improve the shape reconstructions with novel instance-specific optimization strategies that allow reconstructions to faithful fit on each instance while preserving the class-specific priors learned across all images. Experiments on in-the-wild image ensembles show that Hi-LASSIE obtains higher fidelity state-of-the-art 3D reconstructions despite requiring minimum user input.

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attn_cosine_sim google/hi-lassie/networks/extractor.py community (archive-listed) ran Apache-2.0 (permissive) · 08eeaeb47623cd45 · report
bfs google/hi-lassie/main/extract_skeleton.py community (archive-listed) ran Apache-2.0 (permissive) · 135f37701edf71c1 · report
get_max_connected_component google/hi-lassie/main/extract_skeleton.py community (archive-listed) ran fingerprinted Apache-2.0 (permissive) · 107c3f398275bf2c · report
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find_symmetric_pairs google/hi-lassie/main/extract_skeleton.py community (archive-listed) unverified Apache-2.0 (permissive) · 5be6e9126dc4be51 · report
part_center_loss google/hi-lassie/utils/losses.py community (archive-listed) unverified Apache-2.0 (permissive) · 7607686657827741 · report

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