From Language to Instance: Generative Visual Prompting for Zero-shot Camouflaged Object Detection

Traditional Camouflaged Object Detection (COD) methods heavily depend on labor-intensive annotated datasets which require extensive manual effort, resulting in limited generalization. While recent studies have combined Multimodal Large Language Models (MLLMs) and Vision Foundation Models (VFMs) to achieve zero-shot COD, their performance is hindered by modality gap between linguistic semantics and fine-grained visual cues, especially in complex camouflage scenarios. In this paper, we propose Language-to-instance generative visual Prompting (LiP), a novel framework that addresses this limitation by transforming text prompts generated by MLLMs into instance-level visual prompts through a text-to-image generative process. Specifically, we introduce a Diffusion-driven Visual Prompt Generation (DVPG) module that leverages Stable Diffusion model to synthesize visual references, enabling robust homogeneous modality matching for COD. Additionally, we introduce Instruction Contrastive Reasoning (ICR) module to enhance the semantic reliability of prompts by suppressing hallucinated concepts during MLLM inference. To the best of our knowledge, LiP is the first framework that utilize text-to-image generative model to construct instance-level visual prompts in COD task. Extensive experiments on four benchmark datasets demonstrate the effectiveness and strong generalization ability of our approach.