The 3D Gaussian Splatting technique has significantly advanced the construction of radiance fields from multi-view images, enabling real-time rendering. While point-based rasterization effectively reduces computational demands for rendering, it often struggles to accurately reconstruct the geometry of the target object, especially under strong lighting. To address this challenge, we introduce a novel approach that combines octree-based implicit surface representations with Gaussian splatting. Our method consists of four stages. Initially, it reconstructs a signed distance field (SDF) and a radiance field through volume rendering, encoding them in a low-resolution octree. The initial SDF represents the coarse geometry of the target object. Subsequently, it introduces 3D Gaussians as additional degrees of freedom, which are guided by the SDF. In the third stage, the optimized Gaussians further improve the accuracy of the SDF, allowing it to recover finer geometric details compared to the initial SDF obtained in the first stage. Finally, it adopts the refined SDF to further optimize the 3D Gaussians via splatting, eliminating those that contribute little to visual appearance. Experimental results show that our method, which leverages the distribution of 3D Gaussians with SDFs, reconstructs more accurate geometry, particularly in images with specular highlights caused by strong lighting.

翻译：3D高斯溅射技术显著推进了从多视角图像构建辐射场的能力，实现了实时渲染。虽然基于点的光栅化有效降低了渲染的计算需求，但该方法往往难以准确重建目标物体的几何结构，尤其是在强光照条件下。为应对这一挑战，我们提出了一种将基于八叉树的隐式表面表示与高斯溅射相结合的新方法。我们的方法包含四个阶段。首先，通过体渲染重建一个有符号距离场和一个辐射场，并将其编码在一个低分辨率的八叉树中。初始的SDF表示目标物体的粗略几何形状。随后，引入3D高斯作为额外的自由度，并由SDF进行引导。在第三阶段，优化后的高斯进一步提升了SDF的精度，使其能够恢复比第一阶段获得的初始SDF更精细的几何细节。最后，采用优化后的SDF通过溅射进一步优化3D高斯，剔除那些对视觉外观贡献甚微的高斯。实验结果表明，我们的方法利用3D高斯与SDF的分布，重建出更精确的几何形状，尤其是在强光照导致镜面高光的图像中。