oyly/HelloWorld_V1

HelloWorld V1

The social-interaction LoRA for HelloWorld: Enabling Socially Interactive Characters in Video World Models.

📄 Paper: arXiv:2608.05070 · HF paper page

• Base model: LTX-2.3-22B distilled (Lightricks/LTX-2.3)
• File: helloworld_lora_v1.safetensors (rank-32 LoRA)
• What it does: conditions LTX-2.3 on a camera-warp video so the generated clip follows a user-supplied camera trajectory, while an F-key interaction window makes the on-screen character respond toward the camera — turning to the viewer, waving, nodding, or speaking a short greeting.

Example videos

example_videos.zip (86 MB) contains the generated results of the seven official examples shipped with the GitHub repo (same recipes as assets/examples/, previewed as GIFs in the repo README) — full-quality 1280×704 @ 24 fps MP4s with the WASD / arrow / F keyboard overlay and the co-generated audio track (the character speaks in garden_pond, park_yoga, anime_figures, moor_crows, and lakeside_hikers; bear_mascot and shore_skeleton are silent by design).

Usage

Inference code, environment setup, and seven ready-to-reproduce examples: https://github.com/AlayaLab/HelloWorld

git clone https://github.com/AlayaLab/HelloWorld
# put this LoRA at HelloWorld/checkpoints/helloworld_lora_v1.safetensors
cd HelloWorld/inference
INPUT=examples_batch.json GPU=0 bash run_batch.sh

License

This LoRA is fine-tuned from LTX-2.3 and trained on data synthesized by LTX-2.3, which makes it a Derivative of LTX-2 as defined in the LTX-2 Community License Agreement. Accordingly, it is distributed exclusively under that agreement — the complete license text is included in this repository as LICENSE. In particular:

• Your use of this model (and anything you build on it) is subject to the use-based restrictions in Attachment A of the agreement.
• Commercial entities with annual revenues of at least $10,000,000 must obtain a separate paid commercial license from Lightricks — see https://ltx.io/model/licensing.
• If you redistribute this model or further derivatives of it, you must do so under the same agreement and include a complete copy of the license.

LTX-2 is © Lightricks Ltd. This repository is not affiliated with or endorsed by Lightricks; all rights in the base model remain with the Licensor.

Citation

@article{ouyang2026helloworld,
  title   = {HelloWorld: Enabling Socially Interactive Characters in Video World Models},
  author  = {Ouyang, Liangyang and Liu, Ruicong and Chu, Xuangeng and Zhang, Kaipeng and Sato, Yoichi},
  journal = {arXiv preprint arXiv:2608.05070},
  year    = {2026}
}

Contact

oyly@iis.u-tokyo.ac.jp / liangyang.ouyang@shanda.com