Advancing Narrative Long Video Generation via Training-Free Identity-Aware Memory
Jinzhuo Liu1,
Jiangning Zhang1✉,
Wencan Jiang1,
Yabiao Wang2,
Dingkang Liang3,
Zhucun Xue1,
Ran Yi4,
Yong Liu1
1Zhejiang University,
2Tencent Youtu Lab,
3Huazhong University of Science and Technology,
4Shanghai Jiao Tong University
✉Corresponding author
## 🔥 Updates
- __[2026.05.15]__: We release the [github repo](https://github.com/Eddie0521/IAMFlow), the [project page](https://eddie0521.github.io/projects/iamflow/), the quantized [model checkpoints](https://huggingface.co/Eddie0521/IAMFlow-FP8), the [NarraStream-Bench](https://github.com/Eddie0521/NarraStream-Bench), and the [paper](https://arxiv.org/abs/2605.18733).
## 📷 Introduction
💡**TL;DR:**
[IAMFlow](https://arxiv.org/abs/2605.18733) uses explicit identity-aware memory to keep identities consistent across evolving narrative prompts, achieving faster and stronger long video generation on [NarraStream-Bench](https://arxiv.org/abs/2605.18733).
## ✨ Highlights
1. We introduce [**IAMFlow**](https://arxiv.org/abs/2605.18733), a training-free identity-aware memory framework that explicitly organizes historical information around persistent entities and attributes, enabling reliable identity preservation across evolving prompt transitions.
2. We design a systematic inference acceleration pipeline to make the framework computationally practical, combining asynchronous visual verification, adaptive prompt transition, and model quantization to preserve long-term consistency without sacrificing generation speed.
3. We introduce [**NarraStream-Bench**](https://arxiv.org/abs/2605.18733), a modern benchmark suite for assessing long-term consistency in narrative streaming video generation. Extensive experiments and ablation studies demonstrate that IAMFlow achieves superior performance across various metrics while enabling more efficient inference.
## 🛠️ Installation
### 1. Install Requirements
```
git clone git@github.com:Eddie0521/IAMFlow.git
cd IAMFlow
conda create -n iamflow python=3.12 -y
conda activate iamflow
# Install PyTorch first according to your CUDA environment.
python -m pip install torch==2.9.1 torchvision==0.24.1
python -m pip install -r requirements.txt
pip install flash-attn --no-build-isolation
```
### 2. Download Checkpoints
Download models using hf:
``` sh
pip install "huggingface_hub[cli]"
hf download Wan-AI/Wan2.1-T2V-1.3B --local-dir pretrained/Wan2.1-T2V-1.3B
hf download Eddie0521/IAMFlow --local-dir pretrained/iamflow_models
hf download Qwen/Qwen3-VL-2B-Instruct --local-dir pretrained/Qwen3-VL-2B-Instruct
hf download Qwen/Qwen3-4B-Instruct-2507 --local-dir pretrained/Qwen3-4B-Instruct-2507
```
## 🔑 Inference
We deploy DiT, TextEncoder, and LLM on one GPU, while VAE and VLM are deployed on another GPU.
```sh
bash ./scripts/run_iamflow.sh
```
## 📏 Evaluation & Benchmark
See the [NarraStream-Bench](https://github.com/Eddie0521/NarraStream-Bench).
## 🤗 Acknowledgement
- [MemFlow](https://github.com/KlingAIResearch/MemFlow): the codebase we built upon. Thanks for their wonderful work.
- [Self-Forcing](https://github.com/guandeh17/Self-Forcing): the algorithm we built upon. Thanks for their wonderful work.
- [Wan](https://github.com/Wan-Video/Wan2.1): the base model we built upon. Thanks for their wonderful work.
## 🌟 Citation
Please leave us a star 🌟 and cite our paper if you find our work helpful.
```
@misc{liu2026advancingnarrativelongvideo,
title={Advancing Narrative Long Video Generation via Training-Free Identity-Aware Memory},
author={Jinzhuo Liu and Jiangning Zhang and Wencan Jiang and Yabiao Wang and Dingkang Liang and Zhucun Xue and Ran Yi and Yong Liu},
year={2026},
eprint={2605.18733},
archivePrefix={arXiv},
primaryClass={cs.CV},
url={https://arxiv.org/abs/2605.18733},
}
```