HeadRouter: A Training-free Image Editing Framework for MM-DiTs by Adaptively Routing Attention Heads

March 18, 2026 ยท View on GitHub

TL; DR

HeadRouter is a training-free text guided real image editing framework that based on MM-DiT (e.g. SD3 and Flux).

Abstract

Diffusion Transformers (DiTs) have exhibited robust capabilities in image generation tasks. However, accurate text-guided image editing for multimodal DiTs (MM-DiTs) still poses a significant challenge. Unlike UNet-based structures that could utilize self/cross-attention maps for semantic editing, MM-DiTs inherently lack support for explicit and consistent incorporated text guidance, resulting in semantic misalignment between the edited results and texts. In this study, we disclose the sensitivity of different attention heads to different image semantics within MM-DiTs and introduce HeadRouter, a training-free image editing framework that edits the source image by adaptively routing the text guidance to different attention heads in MM-DiTs. Furthermore, we present a dual-token refinement module to refine text/image token representations for precise semantic guidance and accurate region expression. Experimental results on multiple benchmarks demonstrate HeadRouter's performance in terms of editing fidelity and image quality.

Installation & Usage

  1. Clone the repository and install the environment:
    git clone https://github.com/your-repo/HeadRouter.git
    cd HeadRouter/diffusers
    pip install -e .
    
    
  2. Run Inference: You can run the inference script using:
    python infer.py
    

Important Note on Hyper-parameters: Please note that training-free image editing relies heavily on hyper-parameter tuning. You will need to adjust the hyper-parameters based on the specific input image and the type of editing you want to perform.

Tips: The larger the --eta value, the closer the edited result will be to the original image.

Below is our recommended hyper-parameter configuration for various inversion and editing tasks:

Hyper-parameter configuration of our method for inversion and editing tasks

TaskStarting TimeStopping TimeStrength
Object insert061.0
Gender editing081.0
Age editing051.0
Adding glasses6250.7
Stylization060.9

(Note: Stopping Time and Strength are parameters for Controller Guidance)

Citation

If you find this work useful, please consider citing:

@article{xu2024headrouter,
  title={Headrouter: A training-free image editing framework for mm-dits by adaptively routing attention heads},
  author={Xu, Yu and Tang, Fan and Cao, Juan and Kong, Xiaoyu and Zhang, Yuxin and Li, Jintao and Deussen, Oliver and Lee, Tong-Yee},
  journal={ACM Transactions on Graphics},
  publisher={ACM New York, NY}
}

Acknowledgements

This work is built upon several excellent open-source projects and research efforts. We sincerely thank the authors and contributors for making their work publicly available and for advancing the community:

Pipeline

Comparison with baselines

More of our results