---
license: cc-by-sa-4.0
pretty_name: ZDPShift
tags:
  - stereo-matching
  - disparity
  - negative-disparity
  - ZDP
  - blender
  - open-movies
task_categories:
  - depth-estimation
size_categories:
  - 10K<n<100K
configs:
  - config_name: default
    data_files:
      - split: train
        path: zdpshift.parquet
---

# ZDPShift: Beyond the Zero-Disparity Plane in Stereo

<p align="center">
  <img src="images/teaser.png" alt="Same scene rendered at five ZDP shifts; anaglyph + GT disparity + error map" width="100%"/>
</p>

Every public stereo benchmark assumes positive disparity values`d = fB/Z ≥ 0`. Mordern stereoscopic display — cinema 3D, VR, HMDs — actively uses `d < 0`. ZDPShift bridges the gap: the same artist-authored open-movie content rendered at **five ZDP shifts** Δ ∈ {−16, 0, +16, +24, +32} pixels, giving you a controlled continuum from textbook-positive to substantially-crossed disparities, with analytical ground truth at every pixel.

## News:
- [1st July] A technical report is on the way!

## The problem in one plot

<p align="center">
  <img src="images/sota_failure.png" alt="EPE of public SOTA stereo models vs ZDP shift" width="80%"/>
</p>

Every public SOTA fails by **19–60×** the instant disparity crosses zero. ZDPShift gives you the data to fix that.

## What you get

| Split | Source | Scenes | Frames | Pairs | Size |
|---|---|---:|---:|---:|---:|
| `train/` | 6 Blender open movies | 30 | 4,134 | 20,670 | 318 GB |
| `test/` | Caminandes Llamigos | 4 | 271 | 1,355 | 35 GB |

Per pair: **left.png** + **right.png** (1920×1280 open-movie) + **disparity.npy** (signed float32) + **meta.json** (Δ, focal, baseline, K_L, K_R, % crossed).

## Gallery

<p align="center">
  <img src="images/gallery.png" alt="ZDPShift scene gallery across the 8 source franchises" width="100%"/>
</p>

## Geometry

```
d(Z, Δ) = f · B / Z − Δ                    baseline B = 0.10 m,   Δ ∈ {−16, 0, +16, +24, +32} px
```

Cameras stay physically parallel — only the principal points shift by ∓Δ/2. Multi-Δ self-consistency `d(Δᵢ) − d(Δⱼ) = Δⱼ − Δᵢ` holds to a median 0.04 px residual (sub-pixel Cycles noise).

```
rendered_datasets/<split>/<scene>/frame_<N>_<cam>/shift_{-16,+0,+16,+24,+32}/
                                                      ├── left.png
                                                      ├── right.png
                                                      ├── disparity.npy
                                                      └── meta.json
```

## Render protocol

To keep ground truth well-defined at every pixel, three artist settings are overridden:

- **Aperture forced to f/64** — defocus blur kept below sub-pixel
- **Motion blur off** — fast objects have crisp per-frame correspondences
- **Compositor bypassed** — no grading / bloom / flare distortion after correspondence

Everything else (lighting, materials, scene composition, camera path, focal length per shot) is inherited from the original `.blend` unchanged. Cycles 32 spp + OPTIX denoising; sampler noise floor ≈ 0.005/255 per pixel.

## License

**CC-BY-SA-4.0**, inherited from the Blender Studio open movies. Redistribute and adapt with attribution and share-alike.