Shifting the Breaking Point of Flow Matching for Multi-Instance Editing
Carmine Zaccagnino, Fabio Quattrini, Enis Simsar, Marta Tintoré Gazulla, Rita Cucchiara, Alessio Tonioni, Silvia Cascianelli
TL;DR
This paper tackles multi-instance text-guided image editing within flow-matching editors, where a single global velocity field $v_ heta$ risks interference across concurrent edits. It introduces Instance-Disentangled Attention, which partitions joint attention with token-space sets and two masks $M^{\mathrm{dis}}$ and $M^{\mathrm{har}}$, plus an efficient multi-prompt encoding strategy and optional domain-specific fine-tuning. The authors also present an Infographics Editing Benchmark (Crello Edit and InfoEdit) to stress-test locality and editability in many regions. Empirical results show improved edit disentanglement and locality while preserving global coherence in a single pass, with strong performance on both natural images and text-dense infographics, and favorable human and LLM judgments.
Abstract
Flow matching models have recently emerged as an efficient alternative to diffusion, especially for text-guided image generation and editing, offering faster inference through continuous-time dynamics. However, existing flow-based editors predominantly support global or single-instruction edits and struggle with multi-instance scenarios, where multiple parts of a reference input must be edited independently without semantic interference. We identify this limitation as a consequence of globally conditioned velocity fields and joint attention mechanisms, which entangle concurrent edits. To address this issue, we introduce Instance-Disentangled Attention, a mechanism that partitions joint attention operations, enforcing binding between instance-specific textual instructions and spatial regions during velocity field estimation. We evaluate our approach on both natural image editing and a newly introduced benchmark of text-dense infographics with region-level editing instructions. Experimental results demonstrate that our approach promotes edit disentanglement and locality while preserving global output coherence, enabling single-pass, instance-level editing.
