OptiPrune: Boosting Prompt-Image Consistency with Attention-Guided Noise and Dynamic Token Selection
Journal:
arXiv
Published Date:
Jul 1, 2025
Abstract
Text-to-image diffusion models often struggle to achieve accurate semantic
alignment between generated images and text prompts while maintaining
efficiency for deployment on resource-constrained hardware. Existing approaches
either incur substantial computational overhead through noise optimization or
compromise semantic fidelity by aggressively pruning tokens. In this work, we
propose OptiPrune, a unified framework that combines distribution-aware initial
noise optimization with similarity-based token pruning to address both
challenges simultaneously. Specifically, (1) we introduce a distribution-aware
noise optimization module guided by attention scores to steer the initial
latent noise toward semantically meaningful regions, mitigating issues such as
subject neglect and feature entanglement; (2) we design a hardware-efficient
token pruning strategy that selects representative base tokens via patch-wise
similarity, injects randomness to enhance generalization, and recovers pruned
tokens using maximum similarity copying before attention operations. Our method
preserves the Gaussian prior during noise optimization and enables efficient
inference without sacrificing alignment quality. Experiments on benchmark
datasets, including Animal-Animal, demonstrate that OptiPrune achieves
state-of-the-art prompt-image consistency with significantly reduced
computational cost.