RetimeGS：4D 高斯泼溅的连续时间重建
RetimeGS: Continuous-Time Reconstruction of 4D Gaussian Splatting
把 4DGS 的时序混叠问题显式建模为高斯的时间行为定义，并用光流引导初始化与三重渲染监督来约束连续时刻的一致性；做动态场景重建或新视角合成时，可直接借用这套连续时间监督策略来消除插帧鬼影。
原文依据 we identify this limitation as a form of temporal aliasing and propose RetimeGS
摘要译文
由模型翻译 · 术语统一 · 请对照原文核对关键结论时序重定时，即在任意时间戳上重建并渲染动态场景的能力，对慢动作回放、时序编辑和后期制作等应用至关重要。然而，现有大多数 4D 高斯泼溅（4DGS）方法在离散帧索引上过拟合，却难以表示连续时间帧，导致在时间戳之间插值时出现鬼影伪影。我们将这一局限识别为一种时序混叠，并提出 RetimeGS——一种简单而有效的 4DGS 表示，它显式定义 3D 高斯的时间行为，从而缓解时序混叠。为实现平滑且一致的插值，我们引入了光流引导的初始化与监督、三重渲染监督以及其他针对性策略。这些组件共同作用，使得即便在大幅运动下也能实现无鬼影、时序连贯的渲染。在包含快速运动、非刚性形变和严重遮挡的数据集上的实验表明，RetimeGS 在质量和连贯性上均优于最优方法。
英文原文摘要 1095 字符
Temporal retiming, the ability to reconstruct and render dynamic scenes at arbitrary timestamps, is crucial for applications such as slow-motion playback, temporal editing, and post-production. However, most existing 4D Gaussian Splatting (4DGS) methods overfit at discrete frame indices but struggle to represent continuous-time frames, leading to ghosting artifacts when interpolating between timestamps. We identify this limitation as a form of temporal aliasing and propose RetimeGS, a simple yet effective 4DGS representation that explicitly defines the temporal behavior of the 3D Gaussian and mitigates temporal aliasing. To achieve smooth and consistent interpolation, we incorporate optical flow-guided initialization and supervision, triple-rendering supervision, and other targeted strategies. Together, these components enable ghost-free, temporally coherent rendering even under large motions. Experiments on datasets featuring fast motion, non-rigid deformation, and severe occlusions demonstrate that RetimeGS achieves superior quality and coherence over state-of-the-art methods.