We present Exact Volumetric Ellipsoid Rendering (EVER), a method for real-time differentiable emission-only volume rendering. Unlike recent rasterization based approach by 3D Gaussian Splatting (3DGS), our primitive based representation allows for exact volume rendering, rather than alpha compositing 3D Gaussian billboards. As such, unlike 3DGS our formulation does not suffer from popping artifacts and view dependent density, but still achieves frame rates of $\sim\!30$ FPS at 720p on an NVIDIA RTX4090. Since our approach is built upon ray tracing it enables effects such as defocus blur and camera distortion (e.g. such as from fisheye cameras), which are difficult to achieve by rasterization. We show that our method is more accurate with fewer blending issues than 3DGS and follow-up work on view-consistent rendering, especially on the challenging large-scale scenes from the Zip-NeRF dataset where it achieves sharpest results among real-time techniques.

翻译：我们提出精确体积椭球体渲染（EVER），一种用于实时可微分的仅发射型体积渲染方法。与近期基于3D高斯泼溅（3DGS）的光栅化方法不同，我们基于图元的表示允许进行精确的体积渲染，而非对3D高斯公告牌进行阿尔法合成。因此，与3DGS不同，我们的公式不会出现突现伪影和视角相关密度问题，同时仍能在NVIDIA RTX4090上以720p分辨率实现约30 FPS的帧率。由于我们的方法建立在光线追踪之上，它能够实现诸如散景模糊和相机畸变（例如鱼眼相机产生的畸变）等效果，这些效果难以通过光栅化实现。我们证明，与3DGS及后续关于视角一致渲染的工作相比，我们的方法更精确且混合问题更少，尤其是在Zip-NeRF数据集中具有挑战性的大规模场景上，它在实时技术中实现了最清晰的结果。