HiFi4G: High-Fidelity Human Performance Rendering via Compact Gaussian Splatting
Authors: Yuheng Jiang, Zhehao Shen, Penghao Wang, Zhuo Su, Yu Hong, Yingliang Zhang, Jingyi Yu, Lan Xu

We have recently seen tremendous progress in photo-real human modeling and rendering. Yet efficiently rendering realistic human performance and integrating it into the rasterization pipeline remains challenging. In this paper we present HiFi4G an explicit and compact Gaussian-based approach for high-fidelity human performance rendering from dense footage. Our core intuition is to marry the 3D Gaussian representation with non-rigid tracking achieving a compact and compression-friendly representation. We first propose a dual-graph mechanism to obtain motion priors with a coarse deformation graph for effective initialization and a fine-grained Gaussian graph to enforce subsequent constraints. Then we utilize a 4D Gaussian optimization scheme with adaptive spatial-temporal regularizers to effectively balance the non-rigid prior and Gaussian updating. We also present a companion compression scheme with residual compensation for immersive experiences on various platforms. It achieves a substantial compression rate of approximately 25 times with less than 2MB of storage per frame. Extensive experiments demonstrate the effectiveness of our approach which significantly outperforms existing approaches in terms of optimization speed rendering quality and storage overhead.