arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2402.17364cs.CV

学习动态四面体以实现高质量说话头合成

Learning Dynamic Tetrahedra for High-Quality Talking Head Synthesis

University of Chinese Academy of Sciences(中国科学院大学);Ant Group(蚂蚁集团)

Zicheng Zhang, Ruobing Zheng, Ziwen Liu, Congying Han, Tianqi Li, Meng Wang, Tiande Guo, Jingdong Chen, Bonan Li, Ming Yang

AI总结:

本文提出动态四面体(DynTet)混合表示,通过神经网络学习显式动态网格并结合3D可变形模型,在保证几何一致性的同时实现高质量、实时且唇音同步的说话头合成。

摘要:

近期在隐式表示方面的工作,例如神经辐射场(NeRF),推动了从视频序列生成逼真且可动画化的头部化身的发展。这些隐式方法仍然面临视觉伪影和抖动问题,因为缺乏显式几何约束对准确建模复杂面部变形构成了根本性挑战。在本文中,我们提出了动态四面体(DynTet),这是一种新颖的混合表示方法,通过神经网络编码显式动态网格,以确保在各种运动和视角下保持几何一致性。DynTet 由基于坐标的网络参数化,这些网络学习符号距离、变形和材质纹理,并将训练数据锚定到预定义的四面体网格中。借助 Marching Tetrahedra,DynTet 能够高效解码具有一致拓扑结构的带纹理网格,从而通过可微光栅化器实现快速渲染,并通过像素损失进行监督。为了提高训练效率,我们结合了经典的 3D 可变形模型(3D Morphable Models)来促进几何学习,并定义一个规范空间以简化纹理学习。由于 DynTet 采用了有效的几何表示,这些优势可以轻松实现。与先前工作相比,DynTet 在保真度、唇音同步和实时性能方面根据多种指标均展现出显著提升。除了生成稳定且视觉上吸引人的合成视频外,我们的方法还输出动态网格,这有望支持许多新兴应用。

英文摘要:

Recent works in implicit representations, such as Neural Radiance Fields (NeRF), have advanced the generation of realistic and animatable head avatars from video sequences. These implicit methods are still confronted by visual artifacts and jitters, since the lack of explicit geometric constraints poses a fundamental challenge in accurately modeling complex facial deformations. In this paper, we introduce Dynamic Tetrahedra (DynTet), a novel hybrid representation that encodes explicit dynamic meshes by neural networks to ensure geometric consistency across various motions and viewpoints. DynTet is parameterized by the coordinate-based networks which learn signed distance, deformation, and material texture, anchoring the training data into a predefined tetrahedra grid. Leveraging Marching Tetrahedra, DynTet efficiently decodes textured meshes with a consistent topology, enabling fast rendering through a differentiable rasterizer and supervision via a pixel loss. To enhance training efficiency, we incorporate classical 3D Morphable Models to facilitate geometry learning and define a canonical space for simplifying texture learning. These advantages are readily achievable owing to the effective geometric representation employed in DynTet. Compared with prior works, DynTet demonstrates significant improvements in fidelity, lip synchronization, and real-time performance according to various metrics. Beyond producing stable and visually appealing synthesis videos, our method also outputs the dynamic meshes which is promising to enable many emerging applications.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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