Papers › ELLA: Equip Diffusion Models with LLM for Enhanced Semantic Alignment

ELLA: Equip Diffusion Models with LLM for Enhanced Semantic Alignment

8 Mar 2024arXiv:2403.05135archive 2025-07-28

XiWei Hu, Rui Wang, Yixiao Fang, Bin Fu, Pei Cheng, Gang Yu

Diffusion models have demonstrated remarkable performance in the domain of text-to-image generation. However, most widely used models still employ CLIP as their text encoder, which constrains their ability to comprehend dense prompts, encompassing multiple objects, detailed attributes, complex relationships, long-text alignment, etc. In this paper, we introduce an Efficient Large Language Model Adapter, termed ELLA, which equips text-to-image diffusion models with powerful Large Language Models (LLM) to enhance text alignment without training of either U-Net or LLM. To seamlessly bridge two pre-trained models, we investigate a range of semantic alignment connector designs and propose a novel module, the Timestep-Aware Semantic Connector (TSC), which dynamically extracts timestep-dependent conditions from LLM. Our approach adapts semantic features at different stages of the denoising process, assisting diffusion models in interpreting lengthy and intricate prompts over sampling timesteps. Additionally, ELLA can be readily incorporated with community models and tools to improve their prompt-following capabilities. To assess text-to-image models in dense prompt following, we introduce Dense Prompt Graph Benchmark (DPG-Bench), a challenging benchmark consisting of 1K dense prompts. Extensive experiments demonstrate the superiority of ELLA in dense prompt following compared to state-of-the-art methods, particularly in multiple object compositions involving diverse attributes and relationships.

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shihaozhaozsh/lavi-bridge mentioned on GitHubpytorchMIT report
tencentqqgylab/ella mentioned on GitHubpytorch report

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compute_dpg_one_sample tencentqqgylab/ella/dpg_bench/compute_dpg_bench.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · d7c600805e21bbc6 · report
crop_image tencentqqgylab/ella/dpg_bench/compute_dpg_bench.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 10dc0d8ce3bf1721 · report
generate_image_with_fixed_max_length tencentqqgylab/ella/inference.py community (archive-listed) ran · honoured contract Apache-2.0 (permissive) · 90e281d5839c51db · report
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prepare_dpg_data tencentqqgylab/ella/dpg_bench/compute_dpg_bench.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 6e653207d66d539a · report

Tasks

DenoisingImage GenerationLanguage ModellingLarge Language ModelText to Image GenerationText-to-Image Generation

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Methods

AdapterCLIPConcatenated Skip ConnectionConvolutionDiffusionMax PoolingReLUU-Net

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