Pose-Free NeRF & 3DGS Survey

A Survey on Pose-Free Neural Radiance Fields and 3D Gaussian Splatting

A comprehensive review of pose-free neural rendering and 3D reconstruction, covering NeRF and 3DGS methods with only noisy pose estimation or without camera pose priors.

Dongbo Shi1, Lubin Fan2, Bojian Wu2, Shen Cao2, Jinhui Guo2, Ligang Liu1, Renjie Chen1
1University of Science and Technology of China    2Independent Researcher
Paper PDF GitHub Repo Reading List

1. Overview

Neural Radiance Fields (NeRF) and 3D Gaussian Splatting (3DGS) have significantly advanced 3D scene reconstruction and novel view synthesis in recent years. Despite continuous improvements in accuracy, quality, and application scope, these methods fundamentally rely on a critical assumption: precise camera poses for all input images. The reconstruction pipeline typically employ multi-view geometry techniques such as Structure-from-Motion (SfM) or Simultaneous Localization and Mapping (SLAM) to estimate these camera poses. However, in many real-world cases, SfM/SLAM may fail due to weak textures, large viewpoint changes, or non-sequential inputs.

This shifts the focus to the joint estimation of scene structure and camera motion within a unified framework. Understanding and addressing this challenge is essential to unlock the full potential of neural 3D reconstruction in unconstrained real-world environments. To address these challenges of 3D scene reconstruction without reliable camera parameters, recent research has attracted growing interest in adapting and extending neural rendering paradigms (particularly NeRF and 3DGS) to perform pose-free or pose-robust reconstruction.

This survey systematically reviews these pose-free approaches into following categories:

The survey also introduces evaluation methodologies through standardized datasets and metrics, and benchmarks representative methods.

2. Method Taxonomy

Neural Radiance Fields (NeRF)

2.1 Base Model Enhancement

    Network Architecture: GNeRF, SiNeRF, GARF, DBARF
    Robust NeRF: RM-NeRF, Robust-RMNeRF, DiGARR, I-DACS

2.2 Training Strategy Refinement

    Coarse-to-Fine: BARF, CBARF
    Local-to-Global: LU-NeRF, CF-NeRF, CT-NeRF
    Sampling Strategies: NeRFmm, iNeRF, CoPoNeRF, TD-NeRF, FDC-NeRF
    Pose Estimators: Camp, SaNeRF, NeRFtrinsic Four, IR-NeRF, PoseProbesGenObj, CAD-NeRF

2.3 Novel Prior Incorporation

    Depth-based: Bid-NeRF, NoPe-NeRF, AltNeRF, RGBD-NeSR
    Feature-based: SC-NeRF, L2G-NeRF, InvWarp-NeRF, FlowCam, RoGUENeRF
    LiDAR-based: LiDeNeRF, GeoNLF
    Multiview Geometry: DA-NeRF, RPE-BARF, NoPe-NeRF++
    Surface Geometry: SG-NeRF, RSG-NeRF, PoRF

2.4 Applications

    In-the-wild: SAMURAI, NeROIC, SHINOBI, UP-NeRF
    Motion Images: BAD-NeRF, BeNeRF, EBAD-NeRF, USB-NeRF, RS-NeRF
    Sparse View: RegNeRF, SPARF, DaRF, SN2eRF, GC-NeRF, TrackNeRF, Just Flip
    Large-scale: LocalRF, UC-NeRF, DGNR
    Dynamic Scene: BASED, DynaMoN

3D Gaussian Splatting (3DGS)

2.1 Base Model Enhancement

    No existing works fall into this category.

2.2 Training Strategy Refinement

    Progressive Optimization: CF-3DGS, GGRt
    Grouping Strategies: EasySplat, SFGS, KeyGS, Rob-GS

2.3 Novel Prior Incorporation

    Depth-based: PF3Plat, LG-3DGS, ZeroGS, SelfSplat
    Feature-based: HybridBA-3DGS, TrackGS, PCR-GS, 3R-GS

2.4 Applications

    Motion Images: SC4D-3DGS, DreamScene4D, MotionGS, Deblur-GS, EF-3DGS, IncEventGS
    Sparse View: InstantSplat, GaussianScenes, MetaSplats, GBR, GeSplat, NoPoSplat, SPFSplat, COGS
    Medical Surgery: Free-SurGS, Free-DyGS

3. Benchmarks & Datasets

The following datasets are widely used for evaluating pose-free NeRF and 3DGS reconstruction. Their characteristics differ in pose availability, scene type, trajectory patterns, and scale.

Dataset Camera Poses Synthetic Scene Type Trajectory Type #Views #Scenes
NeRF Synthetic Ground-truth Yes Indoor Object-centric ~100 8
LLFF Known No Indoor Forward-facing 20–60 8
DTU Known No Indoor Object-centric 49–64 124
Replica Known Yes Indoor Complex trajectory ~2K 18
Tanks and Temples Known No Outdoor Complex trajectory ~200 8
RealEstate10K Unknown No Indoor Complex trajectory Video ~70K
CO3D V2 Estimated No Mixed Object-centric ~200 ~40K
Static Hikes Estimated No Outdoor Complex trajectory ~10K 12

Synthetic datasets provide accurate pose annotations, while real‑world datasets capture diverse illumination, large motion baselines, and complex geometry—making them essential for benchmarking robust pose‑free reconstruction.

Dataset Gallery

Representative scenes from major datasets can be visualized below.

Dataset Gallery

Figure: Dataset gallery

4. Resources

We maintain a comprehensive Awesome Pose-Free NeRF & 3DGS list on GitHub, covering papers, datasets, benchmarks, and open-source implementations used in this survey.

📘 Awesome List (Main Repository)

Awesome Pose-Free NeRF & 3DGS

A curated and continuously updated list of papers, datasets, and implementations.

📄 Paper Collection

Full paper list categorized by Base Model Enhancement / Strategy / Prior / Applications:
→ View Paper List (NeRF) → View Paper List (3DGS)

🧪 Datasets for Pose-Free Reconstruction

Includes LLFF, DTU, CO3D, Replica, RealEstate10K, Tanks and Temples, etc.
→ View Dataset Links

5. Citation

@article{posefree_survey_2025,
  title={A Survey on Pose-Free Neural Radiance Fields and 3D Gaussian Splatting},
  author={Dongbo Shi,Lubin Fan,Bojian Wu,Shen Cao,Jinhui Guo,Ligang Liu,Renjie Chen},
  year={2025}
}