ZDPShiftDisparity Has a Sign: Stereo Matching Beyond the Zero-Disparity Plane

Six state-of-the-art stereo matching models collapse the moment disparity crosses zero, their error rising by 4.6โ€“37ร—.
Stereoscopic content, from cinema 3D to VR, lives there.

Video

Unseen dataset (with GT): Enables negative disparities. Preserves performances on positive-only datasets.
In the wild: Making stereo matching on real-world 3D movies possible.

Overview

One frame, five ZDP shifts

One frame rendered at five positions of the zero-disparity plane; only the plane moves. Released FoundationStereo never leaves the positive side and returns a plausible disparity map of the wrong sign; after fine-tuning on horizontally translated SceneFlow, never on this benchmark, the same backbone follows the ground truth across the whole signed range.

FoundationStereo across ZDP shifts, zero-shot vs ours.

The blind spot

Every backbone breaks at zero

Six released backbones, three image and three video, degrade the instant disparity crosses zero: EPE reaches 13โ€“150 px at ฮ”=+32 on identical scene content (dashed). Fine-tuned on translated SceneFlow only (solid), all six stay within 2.9โ€“5.2 px across the entire signed range.

EPE vs ZDP shift.

The dataset

ZDPShift

4,275 open-movie frames rendered at five zero-disparity-plane shifts each, with analytical signed ground-truth disparity. Evaluation-only: no released model trains on it.

21,375
stereo pairs
4,275
frames ร— 5 ZDP shifts
32
scenes / 7 open movies
signed
analytical GT disparity
ZDPShift scene gallery.

Results

Flat across the full signed range

End-point error (px, native) at the hardest shift, ฮ”=+32, on the full benchmark of 21,375 pairs โ€” 960-px inference. No model sees any benchmark data: training is horizontally translated SceneFlow only. Frozen keeps the pretrained matching features fixed and trains only the layers that read disparity out of them.

ModelZero-shot+ ours (full)+ ours (frozen features)
RAFT-Stereo149.74.684.89
IGEV-Stereo44.93.974.06
FoundationStereo75.32.903.01
DynamicStereo20.85.195.19
BiDAStereo36.24.494.51
StereoAnyVideo13.03.984.11