EMMA: Your Text-to-Image Diffusion Model Can Secretly Accept Multi-Modal Prompts
Yucheng Han, Rui Wang, Chi Zhang, Juntao Hu, Pei Cheng, Bin Fu, Hanwang Zhang
TL;DR
EMMA introduces a multi-modal prompting framework for diffusion-based image generation built on the ELLA model. It uses Assemblable Gated Perceiver Resampler (AGPR) blocks to inject non-text modalities via cross-attention while freezing the base model, enabling easy integration with existing diffusion systems. The approach supports composing multiple modalities at inference without additional training and is compatible with Stable Diffusion-based pipelines. Empirical results on common object and portrait datasets demonstrate high fidelity and robust multi-modal control, with visualizations illustrating effective modular fusion and potential for broader applications including personalized storytelling and video generation.
Abstract
Recent advancements in image generation have enabled the creation of high-quality images from text conditions. However, when facing multi-modal conditions, such as text combined with reference appearances, existing methods struggle to balance multiple conditions effectively, typically showing a preference for one modality over others. To address this challenge, we introduce EMMA, a novel image generation model accepting multi-modal prompts built upon the state-of-the-art text-to-image (T2I) diffusion model, ELLA. EMMA seamlessly incorporates additional modalities alongside text to guide image generation through an innovative Multi-modal Feature Connector design, which effectively integrates textual and supplementary modal information using a special attention mechanism. By freezing all parameters in the original T2I diffusion model and only adjusting some additional layers, we reveal an interesting finding that the pre-trained T2I diffusion model can secretly accept multi-modal prompts. This interesting property facilitates easy adaptation to different existing frameworks, making EMMA a flexible and effective tool for producing personalized and context-aware images and even videos. Additionally, we introduce a strategy to assemble learned EMMA modules to produce images conditioned on multiple modalities simultaneously, eliminating the need for additional training with mixed multi-modal prompts. Extensive experiments demonstrate the effectiveness of EMMA in maintaining high fidelity and detail in generated images, showcasing its potential as a robust solution for advanced multi-modal conditional image generation tasks.
