Papers › NeRFactor: Neural Factorization of Shape and Reflectance Under an Unknown Illumination

NeRFactor: Neural Factorization of Shape and Reflectance Under an Unknown Illumination

3 Jun 2021arXiv:2106.01970archive 2025-07-28

Xiuming Zhang, Pratul P. Srinivasan, Boyang Deng, Paul Debevec, William T. Freeman, Jonathan T. Barron

We address the problem of recovering the shape and spatially-varying reflectance of an object from multi-view images (and their camera poses) of an object illuminated by one unknown lighting condition. This enables the rendering of novel views of the object under arbitrary environment lighting and editing of the object's material properties. The key to our approach, which we call Neural Radiance Factorization (NeRFactor), is to distill the volumetric geometry of a Neural Radiance Field (NeRF) [Mildenhall et al. 2020] representation of the object into a surface representation and then jointly refine the geometry while solving for the spatially-varying reflectance and environment lighting. Specifically, NeRFactor recovers 3D neural fields of surface normals, light visibility, albedo, and Bidirectional Reflectance Distribution Functions (BRDFs) without any supervision, using only a re-rendering loss, simple smoothness priors, and a data-driven BRDF prior learned from real-world BRDF measurements. By explicitly modeling light visibility, NeRFactor is able to separate shadows from albedo and synthesize realistic soft or hard shadows under arbitrary lighting conditions. NeRFactor is able to recover convincing 3D models for free-viewpoint relighting in this challenging and underconstrained capture setup for both synthetic and real scenes. Qualitative and quantitative experiments show that NeRFactor outperforms classic and deep learning-based state of the art across various tasks. Our videos, code, and data are available at people.csail.mit.edu/xiuming/projects/nerfactor/.

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compute_depth_and_normal google/nerfactor/nerfactor/geometry_from_nerf.py official repository unverified Apache-2.0 (permissive) · b4ebd4ad115cecb0 · report
conv google/nerfactor/nerfactor/networks/layers.py official repository unverified Apache-2.0 (permissive) · b4ac623f29916a14 · report
deconv google/nerfactor/nerfactor/networks/layers.py official repository unverified Apache-2.0 (permissive) · 2701f7ec7df9aaa0 · report
eval_sigma_mlp google/nerfactor/nerfactor/geometry_from_nerf.py official repository unverified Apache-2.0 (permissive) · 0e8e25bf567a85d8 · report
upconv google/nerfactor/nerfactor/networks/layers.py official repository unverified Apache-2.0 (permissive) · 8d403fc0866ffbb7 · report

Tasks

Depth PredictionImage RelightingInverse RenderingNeRFObjectSurface Normals EstimationSurface Reconstruction

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Relighting Stanford-ORB NeRFactor HDR-PSNR 23.54 #4 of 7 Archive leaderboard report
Image Relighting Stanford-ORB NeRFactor LPIPS 0.048 #4 of 7 Archive leaderboard report
Image Relighting Stanford-ORB NeRFactor SSIM 0.969 #4 of 7 Archive leaderboard report
Inverse Rendering Stanford-ORB NeRFactor HDR-PSNR 23.54 #4 of 7 Archive leaderboard report
Surface Normals Estimation Stanford-ORB NeRFactor Cosine Distance 0.29 #7 of 7 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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