Papers › PIANO: A Parametric Hand Bone Model from Magnetic Resonance Imaging

PIANO: A Parametric Hand Bone Model from Magnetic Resonance Imaging

21 Jun 2021arXiv:2106.10893archive 2025-07-28

Yuwei Li, Minye Wu, Yuyao Zhang, Lan Xu, Jingyi Yu

Hand modeling is critical for immersive VR/AR, action understanding, or human healthcare. Existing parametric models account only for hand shape, pose, or texture, without modeling the anatomical attributes like bone, which is essential for realistic hand biomechanics analysis. In this paper, we present PIANO, the first parametric bone model of human hands from MRI data. Our PIANO model is biologically correct, simple to animate, and differentiable, achieving more anatomically precise modeling of the inner hand kinematic structure in a data-driven manner than the traditional hand models based on the outer surface only. Furthermore, our PIANO model can be applied in neural network layers to enable training with a fine-grained semantic loss, which opens up the new task of data-driven fine-grained hand bone anatomic and semantic understanding from MRI or even RGB images. We make our model publicly available.

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4ran · our draft was wrong
1ran · fixture could not drive it
2unverified

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batch_rodrigues reyuwei/PIANO_model/PIANOLayer.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · dba91b8424db46e4 · report
quat2mat reyuwei/PIANO_model/PIANOLayer.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · bec37e39340a8433 · report
subtract_flat_id reyuwei/PIANO_model/PIANOLayer.py official repository ran · our draft was wrong no licence file found · pointer only · b080eb0261b5054e · report
th_pack reyuwei/PIANO_model/PIANOLayer.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · a012fac19e3c7477 · report
th_posemap_axisang_2output reyuwei/PIANO_model/PIANOLayer.py official repository ran · fixture could not drive it no licence file found · pointer only · 324dca08208c793e · report
PIANOLayer reyuwei/PIANO_model/PIANOLayer.py official repository unverified no licence file found · pointer only · d130402dd67d59fc · report
th_with_zeros reyuwei/PIANO_model/PIANOLayer.py official repository unverified no licence file found · pointer only · cd37580add3ccba5 · report

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