Encode & estimate
A shared multi-view encoder extracts reference features and predicts camera parameters from unposed images.
Fully self-supervised novel view synthesis
National University of Defense Technology · Changsha, China
Learning to see new views, without camera annotations.

01 / Overview
Implicit modeling, with geometry built into the rendering process.
Novel view synthesis from unposed multi-view images requires learning scene representations and camera parameters together. Free latent-space rendering is flexible, but can yield weakly grounded cameras. Explicit 3D representations provide stronger geometric grounding, but introduce heavier parameterization and more fragile optimization.
IRIS represents the scene as a latent neural field. It queries that field under self-predicted cameras: features from reference images are projected onto sampled 3D points, aggregated across views, and then composed along target rays. This preserves the flexibility of implicit modeling while introducing geometric structure into rendering.
Novel view synthesis from unposed multi-view images remains challenging, as the model must jointly learn scene representations and camera parameters without pose supervision. Existing approaches largely fall into two extremes: implicit latent-space rendering is flexible and easy to optimize, but often yields weakly grounded camera estimation; explicit 3D representations provide stronger geometric grounding, but introduce heavier parameterization and more fragile optimization. In this paper, we present IRIS, a fully self-supervised framework that provides a practical middle ground between these two paradigms. Instead of decoding free latent tokens or reconstructing fully explicit 3D primitives, IRIS represents the scene as a latent neural field and renders novel views by querying this field under self-predicted cameras. Specifically, projected features from reference views are aggregated at sampled 3D points to form point-wise latent features, which are then composed along target rays for rendering. This design preserves the flexibility and optimization stability of implicit modeling, while introducing stronger geometric structure than unconstrained latent rendering. Extensive experiments show that IRIS achieves strong novel view synthesis quality with competitive pose accuracy under fully self-supervised learning.
02 / Video
Novel views. Predicted cameras.
A closer look at the results.
IRIS project demonstration 01:48 Download original video ↗
03 / Method
A shared encoder. Self-predicted cameras.
Geometry-aware implicit rendering.

A shared multi-view encoder extracts reference features and predicts camera parameters from unposed images.
At each sampled 3D point, projected reference features are aggregated across views into a point-wise latent feature.
A ray transformer composes the sampled point features to predict target colors, trained without pose annotations.
04 / Results
Evaluated on indoor and outdoor scenes,
including unseen datasets.
With image-only training supervision
PSNR over E-RayZer, DL3DV-only training
PSNR with DL3DV-only training

Single-source training on DL3DV · Paper, Table 3
| Evaluation dataset | Method | PSNR ↑ | SSIM ↑ | LPIPS ↓ | RPA @15° ↑ |
|---|---|---|---|---|---|
| DL3DV Random order | E-RayZer | 21.124 | 0.701 | 0.271 | 0.811 |
| IRIS (ours) | 25.324 | 0.791 | 0.215 | 0.863 | |
| NRGBD | E-RayZer | 26.476 | 0.860 | 0.144 | 0.800 |
| IRIS (ours) | 31.404 | 0.921 | 0.128 | 0.861 | |
| ScanNet++ | E-RayZer | 21.992 | 0.744 | 0.259 | 0.252 |
| IRIS (ours) | 22.938 | 0.763 | 0.276 | 0.333 | |
| 7Scenes | E-RayZer | 26.727 | 0.870 | 0.175 | 0.729 |
| IRIS (ours) | 30.783 | 0.907 | 0.140 | 0.749 |
Each test sample contains 16 reference views and 8 target views. Re10K results above use Re10K-only training (Table 5); the comparison table uses DL3DV-only training. IRIS trades additional rendering cost for synthesis quality; see the paper for full pose metrics, mixed-source results, and inference latency.
05 / Citation
If you find this work useful, please consider citing it.
@misc{li2026iris,
title = {IRIS: Implicit Rendering Matters for Pose-Free
Novel View Synthesis},
author = {Li, Wenyu and Liu, Sidun and Qiao, Peng
and Dou, Yong and Hu, Tongrui},
year = {2026},
url = {https://leo-frank.github.io/IRIS/}
}