AMAP, Alibaba Group · Tsinghua University

OneLA: Learning Many Worlds
from Latent Actions

A shared action space. A world of possibilities.

Ziyu Zhu1Zhaoxu Sun1Fan Jiang1,‡Chiyu Wang1Junfeng Ni1,2,§Mu Xu1

1 AMAP, Alibaba Group2 Tsinghua University

‡ Corresponding author. § Work done during internship at AMAP, Alibaba Group.

1.79Mvideo clips for LAM pretraining
32Dcontinuous latent action space
Oneshared world-model backbone

01 / The idea

Many worlds.
A common language of action.

Turning in a game, moving through a room, and controlling a robot all change what we see. Yet their native action interfaces are different, and most videos come without action labels.

OneLA learns a shared representation of visual transitions directly from video. A continuous latent action describes the change; the current observation supplies the context in which that change unfolds.

ONE SHARED INTERFACEConceptual illustration
Illustrative frame at an earlier timeIllustrative frame at a later time

Video frame pairs

Observed transitions across domains

q₁q₂q₃z

Shared latent action

32 coefficients · orthogonal dictionary

Illustrative video observationReconstruction

Predict the next frame

Current observation + transition embedding

01 / 03

Learn transition coefficients from ordered frame pairs without action labels. A shared orthonormal dictionary embeds these coefficients for next-frame reconstruction.

Read the abstract +

Learning world models across diverse domains calls for a unified control space, yet action interfaces vary across domains and action annotations are often scarce. Latent actions learned directly from videos offer a promising way to establish such a space without explicit action supervision. However, learning shared latent actions across domains remains challenging, as variations in appearance, embodiment, and dynamics can entangle domain-specific visual cues with transferable transition structure.

We introduce OneLA, a simple framework that learns continuous latent actions through a shared orthogonal dictionary and a common predictive objective, without task-specific designs or cross-domain alignment losses during latent action pretraining. These latent actions provide a shared conditioning interface for world models, with lightweight adapters mapping native control commands into the same space. Conditioned on latent actions and the current visual state, the world model predicts context-dependent transitions for controllable rollout.

OneLA improves action readout across domains and reduces action cycle-transfer rotation error by 24.8% over the strongest evaluated baseline. A joint-training comparison further shows a 20.5% improvement in Human Preference Score v3 for real-scene generation. These results suggest a path toward general-purpose world models that learn from diverse videos and support flexible control through latent action space.

02 / Controllable worlds

One interface.
Different ways to move.

Explore selected generated rollouts across four domains, from virtual environments to physical interactions.

GENERATED ROLLOUT 01 / 04

Moving through
virtual worlds.

Character movement and changes in viewpoint in a game environment, conditioned through the latent action interface.

Game environment24 fps · original speed

Selected qualitative examples. The robotics example plays at its original 3 fps.

Cross-domain & cross-scene action transfer

Carry the motion into another scene.

6 selected cases · Across domains & scenes

The reference supplies the motion; a different initial observation supplies the scene. Explore motion transfer across real scenes, game environments, and characters.

CASE 01Game → Real

City street → woodland trail

REFERENCE VIDEOGame
GENERATED TRANSFERReal
0.0 / 7.6s
CASE 02Game → Real

Abandoned building → billiard room

REFERENCE VIDEOGame
GENERATED TRANSFERReal
0.0 / 7.6s
CASE 03Game → Real

Twilight city → desert trail

REFERENCE VIDEOGame
GENERATED TRANSFERReal
0.0 / 7.6s
CASE 04Real → Game

Woodland trail → city street

REFERENCE VIDEOReal
GENERATED TRANSFERGame
0.0 / 2.6s
CASE 05Game → Game

Frontier grassland → alien landscape

REFERENCE VIDEOGame
GENERATED TRANSFERGame
0.0 / 7.6s
CASE 06Cross-scene character motion

Rural road → library hall

REFERENCE VIDEOGame
GENERATED TRANSFERNew scene
0.0 / 7.6s

Reference and generated videos play together at 16 fps. These selected examples illustrate cross-domain and cross-scene motion transfer.

03 / Method

From visual change
to controllable prediction.

01 / REPRESENT

Learn the transition.

A latent action model encodes frame pairs into continuous coefficients. A learned dictionary, orthonormalized with QR, embeds them for reconstruction.

at = Qzt QᵀQ = I
02 / ALIGN

Map native controls.

With the latent action model frozen, lightweight MLPs learn to map labeled, domain-specific commands into the shared latent space.

ut(k) → gk → zt
03 / GENERATE

Predict video and action.

A shared Wan2.2-TI2V-5B backbone learns from inferred latent actions or mapped controls, with joint video and realized-transition action prediction.

ℒ = ℒvideo + λℒact
OneLA method: orthogonal latent action learning from frame pairs, followed by joint video and action prediction with inferred latent actions or mapped commands.
OneLA architecture. The learned dictionary constrains the geometry of the representation; it does not assign semantic meanings to individual axes. View full size ↗

04 / Evidence

Shared representations.
Measurable improvements.

Results reported in the paper, with each comparison tied to its evaluation setting.

24.8% ↓

Cycle-transfer rotation error

Relative reduction versus OLaF across 40 action-transfer cycles. Rotation RPE: 0.496° → 0.373°.

20.5% ↑

Real-scene HPSv3

Training with inferred latent conditions versus zero conditions on unlabeled videos; evaluated on 30 scenes.

36% → 22%

Human-verified collisions

A separate action-prediction-loss ablation: 18/50 cases without the loss, 11/50 with it.

Video prediction & action cycle transfer

Same OneLA backbone across benchmarks
Reported world-model benchmarks. Bold denotes best and underline denotes second best among evaluated methods.
MethodnuScenesRT-1MINDCycle transfer
PSNR ↑SSIM ↑PSNR ↑SSIM ↑RPEt ↓RPEr ↓RPEt ↓RPEr ↓
OLaF15.920.60118.780.7850.0450.5980.0920.496
AdaWorld10.080.20817.160.7430.0440.6010.1020.535
DiLA15.490.60417.280.7340.0510.9450.0990.666
OneLA ours16.130.62517.780.7710.0370.5530.0770.373

Video prediction uses mapped native commands; cycle transfer uses video-derived actions. RPEr is in degrees. See Table 2 for the full metric set and the paper for the evaluation protocol.

05 / Research film

The story in motion.

An overview of the idea, the method, and selected results.

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Citation

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please consider citing OneLA.

BIBTEX
@misc{zhu2026onela,
  title  = {OneLA: Learning Many Worlds from Latent Actions},
  author = {Zhu, Ziyu and Sun, Zhaoxu and Jiang, Fan and
            Wang, Chiyu and Ni, Junfeng and Xu, Mu},
  year   = {2026},
  eprint = {2610.20160},
  archivePrefix = {arXiv},
  primaryClass = {cs.CV},
  url    = {https://arxiv.org/abs/2610.20160}
}