FreGS: 3D Gaussian Splatting with Progressive Frequency Regularization
Authors: Jiahui Zhang, Fangneng Zhan, Muyu Xu, Shijian Lu, Eric Xing

3D Gaussian splatting has achieved very impressive performance in real-time novel view synthesis. However it often suffers from over-reconstruction during Gaussian densification where high-variance image regions are covered by a few large Gaussians only leading to blur and artifacts in the rendered images. We design a progressive frequency regularization (FreGS) technique to tackle the over-reconstruction issue within the frequency space. Specifically FreGS performs coarse-to-fine Gaussian densification by exploiting low-to-high frequency components that can be easily extracted with low-pass and high-pass filters in the Fourier space. By minimizing the discrepancy between the frequency spectrum of the rendered image and the corresponding ground truth it achieves high-quality Gaussian densification and alleviates the over-reconstruction of Gaussian splatting effectively. Experiments over multiple widely adopted benchmarks (e.g. Mip-NeRF360 Tanks-and-Temples and Deep Blending) show that FreGS achieves superior novel view synthesis and outperforms the state-of-the-art consistently.