---
license: other
license_name: mixed-see-subdir-readmes
language:
- en
task_categories:
- question-answering
- text-generation
pretty_name: "Motion-SMD: Structured Motion Descriptions and Preprocessed Motion-Language Data"
tags:
- human-motion
- motion-captioning
- motion-qa
- biomechanics
- llm
- structured-text
size_categories:
- 10K<n<100K
---

# Motion-SMD Data

Data release for **"Encoder-Free Human Motion Understanding via Structured Motion Descriptions"**.

- 🌐 **Project page:** https://yaozhang182.github.io/motion-smd/
- 💻 **Code:** https://github.com/yaozhang182/motion-smd
- 🤗 **LoRA adapters:** https://huggingface.co/zyyy12138/motion-smd-lora
- 📄 **Paper (arXiv):** https://arxiv.org/abs/2604.21668

---

## What's here

Four subdirectories, each with its own `README.md` describing files, provenance, and license:

| Subdir | Contents | Our contribution? |
|---|---|---|
| [`smd_texts/`](./smd_texts) | Pre-generated Structured Motion Description JSONs (17 variants × 3 datasets) | **Ours** — derived via our rule-based pipeline |
| [`babel_qa/`](./babel_qa) | BABEL-QA joints + original QA + our 10-option QA | Derived (joints/questions from IMoRe); **10-option QA is ours** |
| [`humman_qa/`](./humman_qa) | HuMMan-QA joints + original QA + our 10-option QA | Derived (joints/questions from IMoRe); **10-option QA is ours** |
| [`humanml3d/`](./humanml3d) | HumanML3D 22-joint sequences, texts, splits, Mean/Std | Subset mirror for reproducibility |

## Why this repo

The main repository (`github.com/yaozhang182/motion-smd`) ships only code.
Reproducing the paper requires ~5 GB of preprocessed data, including SMDs
computed from the three upstream datasets. This HF repo bundles all of that
so `git clone` + `huggingface-cli download` is enough to reach the training
step.

## Quick start

```bash
pip install huggingface_hub

# Option 1: download the entire dataset (~5 GB)
huggingface-cli download zyyy12138/motion-smd-data --repo-type dataset --local-dir motion-smd-data

# Option 2: download just one subdir (e.g., SMDs only, if you already have the
# upstream data locally)
huggingface-cli download zyyy12138/motion-smd-data --repo-type dataset \
    --include "smd_texts/*" --local-dir motion-smd-data
```

Then symlink or move the subdirectories into the paths the code expects:

```
motion_smd/
├── data/babel_qa/{joints,questions,questions_10opt,angle_texts_v5*.json}
├── data/humman_qa/{joints,questions,questions_10opt,angle_texts_v5*.json}
└── captioning/data/humanml3d/{new_joints,texts,Mean.npy,Std.npy,train.txt,val.txt,test.txt,angle_texts_v5*.json}
```

See the root `README.md` of the [code repo](https://github.com/yaozhang182/motion-smd)
for the exact expected layout.

## License

This release combines several sources under different licenses:

- **Our derivatives** (`smd_texts/*`, `*_qa/questions_10opt/*`) are released
  under the **MIT License**.
- **Upstream data** mirrored here (`*_qa/joints/`, `*_qa/questions/`,
  `humanml3d/*`) retains its original license. See each subdir README.

If in doubt for a given file, consult the subdir README and the upstream
source linked from it.

## Citation

If you use this data, please cite the paper and the upstream sources listed
in each subdir.

```bibtex
@article{zhang2026smd,
  title   = {Encoder-Free Human Motion Understanding via Structured Motion Descriptions},
  author  = {Zhang, Yao and Liu, Zhuchenyang and Ploetz, Thomas and Xiao, Yu},
  journal = {arXiv preprint arXiv:2604.21668},
  year    = {2026}
}
```

## Contact

Yao Zhang — `yao.1.zhang@aalto.fi`