🤖 AI Summary
To address three key bottlenecks in animatable 3D human avatar reconstruction from a single portrait image—pose and composition sensitivity, scarcity of training data, and instability in proxy mesh estimation—this paper proposes the first unified framework. Methodologically, it introduces: (1) a Dual-UV representation that decouples appearance and geometry via Core-UV and Shell-UV branches, eliminating pose- and composition-induced feature shifts; (2) a generative synthetic data manifold integrating GAN-driven diverse 2D renderings with geometrically consistent 3D synthesis; and (3) a visibility-aware robust proxy mesh tracking mechanism. Trained solely on synthetic upper-body data, our method achieves state-of-the-art performance on head and upper-body reconstruction, while delivering highly competitive results for full-body reconstruction. Crucially, it significantly improves generalization to in-the-wild scenarios, demonstrating strong robustness under unconstrained conditions.
📝 Abstract
We present a unified framework for reconstructing animatable 3D human avatars from a single portrait across head, half-body, and full-body inputs. Our method tackles three bottlenecks: pose- and framing-sensitive feature representations, limited scalable data, and unreliable proxy-mesh estimation. We introduce a Dual-UV representation that maps image features to a canonical UV space via Core-UV and Shell-UV branches, eliminating pose- and framing-induced token shifts. We also build a factorized synthetic data manifold combining 2D generative diversity with geometry-consistent 3D renderings, supported by a training scheme that improves realism and identity consistency. A robust proxy-mesh tracker maintains stability under partial visibility. Together, these components enable strong in-the-wild generalization. Trained only on half-body synthetic data, our model achieves state-of-the-art head and upper-body reconstruction and competitive full-body results. Extensive experiments and analyses further validate the effectiveness of our approach.