Localize Any Object in X-Ray Security Scanswithout Human Annotation

Explore the model

Selected X-ray scan LAO-X predicted mask

Beyond familiar objects.

Real examples from the paper ↙

Qualitative comparison

Cleaner boundaries and more complete instances, even under heavy overlap.

View in the paper ↗
TOP-5 CONFIDENT MASKS
Original predictions from Figure 3. Grayscale scans make masks easier to inspect.

Performance across six benchmarks

Stronger box localization than SAM2, SAM3, and UnSAMv2 across all six test-only datasets.

SAM2SAM3UnSAMv2LAO-X (ours)
↗

64.06%mIoU on PIXray

More precise masks.
+12.54 points over UnSAMv2.

Segmentation results ↗

Method overview

Unlabeled scans become a world of structured training examples.

01

Discover the objects

Unlabeled source scan example→An object-centric mask example

Saliency-guided mining turns unlabeled scans into an object bank.

02

Compose with physics

Ascene = Abg + ∑ Ai

Combine dual-energy scans in the Beer–Lambert absorbance domain.

03

Build up the challenge

2–4 objects0.05 max overlap

From sparse scenes to heavy overlap.

04

See the whole picture

Real LAO-X holistic mask from the paper

Use a point and granularity to localize a part or a complete instance.

BibTeX

NeurIPS 2026
@inproceedings{cai2026laox,
  title     = {Localize Any Object in {X-Ray} Security Scans without Human Annotation},
  author    = {Cai, Yaqi and Liu, Mingxuan and Vaquero, Lorenzo and Wang, Ning and Pu, Nan and Xue, Feng and Ricci, Elisa and Sebe, Nicu},
  booktitle = {Advances in Neural Information Processing Systems},
  year      = {2026}
}