ECC-NeRF: Anti-Aliasing Neural Radiance Fields With Elliptic Cone-Casting for Diverse Camera Models

Anti-aliasing is a crucial research topic in computer graphics, which can significantly enhance the rendering quality of neural radiance fields (NeRF). Recent studies have introduced effective anti-aliasing NeRF methods, utilizing cone-casting to replace ray-casting and modeling the 3D observation area of pixels as circular cones. The cone-casting strategy has successfully reduced blurring and aliasing in novel view rendering. However, we have observed that the light cones are not standard circular cones because the camera projection model distorts them into elliptic cones of diverse sizes and shapes. This finding motivates us to model pixel light cones as anisotropic elliptic cones and propose an elliptic cone-casting-based anti-aliasing NeRF method called “ECC-NeRF". Specifically, we first derive the elliptic cone models for common pinhole, fisheye, and panoramic cameras based on their camera projection models. Then, we integrate the proposed elliptic cone-casting into two representative cone-casting-based anti-aliasing NeRF methods: Mip-NeRF and Zip-NeRF. Our experimental evaluations on multiple datasets demonstrate that our method can achieve more accurate multi-scale anisotropic representation and better novel view rendering quality with negligible additional computation cost.