Modality-Agnostic Prompt Learning for Multi-Modal Camouflaged Object Detection
Authors: Hao Wang, Jiqing Zhang, Xin Yang, Baocai Yin, Lu Jiang, Zetian Mi, Huibing Wang
Organizations: Information Science and Technology College, Dalian Maritime University, Liaoning, 116026, China · Dalian University of Technology, Liaoning, 116024, China · Beijing University of Technology, Beijing, 100124, China
Camouflaged Object Detection (COD) aims to segment objects that blend seamlessly into complex backgrounds, with growing interest in exploiting additional visual modalities to enhance robustness through complementary information. However, most existing approaches generally rely on modality-specific architectures or customized fusion strategies, which limit scalability and cross-modal generalization. To address this, we propose a novel framework that generates modality-agnostic multi-modal prompts for the Segment Anything Model (SAM), enabling parameter-efficient adaptation to arbitrary auxiliary modalities and significantly improving overall performance on COD tasks. Specifically, we model multi-modal learning through interactions between a data-driven content domain and a knowledge-driven prompt domain, distilling task-relevant cues into unified prompts for SAM decoding. We further introduce a lightweight Mask Refine Module to calibrate coarse predictions by incorporating fine-grained prompt cues, leading to more accurate camouflaged object boundaries. Extensive experiments on RGB-Depth, RGB-Thermal, and RGB-Polarization benchmarks validate the effectiveness and generalization of our modality-agnostic framework.
Figures & tables
Fig. 1: The Fβw scores with respect to the trainable parameters of different methods on COD10K (RGB-Depth), PCOD-1200 (RGB-Polarization), and VIAC (RGB-Thermal) datasets.
Fig. 2: Overview of our proposed framework. The framework adopts a dual-stream architecture where RGB and auxiliary modalities are processed via a frozen SAM image encoder and a PVT encoder, respectively, to construct the content domain through feature summation. In Content-Prompt Interaction Module (CPIM), a set of learnable parameters serves as the prompt domain prototype, interacting with the content domain to achieve synergy between data-driven and knowledge-driven representations. Finally, the enhanced content features, along with learnable auxi-tokens and SAM’s original tokens, are fed into the mask decoder, followed by a Mask Refine Module (MRM) to produce the final precise segmentation.
Methods
Pub. Year
CAMO
COD10K
NC4K
CHAMELEON
Sα↑
Fβw↑
Eϕ↑
M↓
Sα↑
Fβw↑
Eϕ↑
M↓
Sα↑
Fβw↑
Eϕ↑
M↓
Sα↑
Fβw↑
Eϕ↑
M↓
RGB-based Methods
SINet Fan et al. [2020]
CVPR’20
0.751
0.606
0.771
0.100
0.771
0.551
0.806
0.051
0.808
0.723
0.883
0.058
0.869
0.740
0.891
0.044
PFNet Mei et al. [2021]
CVPR’21
0.782
0.695
0.845
0.085
0.800
0.660
0.880
0.040
0.829
0.745
0.891
0.053
0.882
0.810
0.927
0.053
FSPNet Huang et al. [2023]
CVPR’23
0.856
0.799
0.899
0.050
0.851
0.735
0.895
0.026
0.879
0.816
0.915
0.035
-
-
-
-
FGANet Zhai et al. [2022]
NeurIPS’23
0.803
0.748
0.871
0.068
0.821
0.678
0.895
0.031
-
-
-
-
0.902
0.840
0.947
0.030
TABLE I: Comparison of SOTA methods on multiple RGB-Depth datasets in terms of Sα , Fβw , Eϕ , and M . The best results are highlighted in bold . * represents the SAM-based methods.
Fig. 3: Qualitative comparison of detection results on RGB-D and RGB-P camouflaged object detection datasets.
Methods
Pub.’Year
Sα↑
Eϕ↑
M↓
Fβw↑
RGB-based Methods
PFNet Mei et al. [2021]
CVPR’21
0.876
0.946
0.013
0.788
SINet-V2 Fan et al. [2021]
TPAMI’22
0.882
0.941
0.013
-
ZoomNet Pang et al. [2022]
CVPR’22
0.897
0.922
0.010
-
BSANet Zhu et al. [2022]
AAAI’22
0.903
0.945
0.011
-
HQSAM* Ke et al. [2023]
NeurIPS’23
0.936
0.973
0.008
0.909
TABLE II: Quantitative comparisons with SOTAs on PCOD-1200. The best results are highlighted in bold . * represents the SAM-based methods.
Methods
Pub.’Year
Sα↑
Eϕ↑
M↓
Fβw↑
RGB-based Methods
HQSAM* Ke et al. [2023]
NeurIPS’23
0.929
0.981
0.011
0.925
ZoomNetxt Pang et al. [2024]
TPAMI’24
0.934
0.981
0.011
0.920
UTNet Sun et al. [2025]
TMM’25
0.903
0.969
0.016
0.876
PlantCamo Yang et al. [2024]
AIR’25
0.926
0.982
0.010
0.918
ESCNet Ye et al. [2025]
ICCV’25
0.928
0.979
0.011
0.919
TABLE III: Quantitative comparisons with SOTAs on the VIAC (RGB-T) dataset. The best results are highlighted in bold . * represents the SAM-based methods.
Setting
#
Method
RGB-D (COD10K)
RGB-P (PCOD-1200)
RGB-T (VIAC)
Sα↑
Fβw↑
Eϕ↑
M↓
Sα↑
Fβw↑
Eϕ↑
M↓
Sα↑
Fβw↑
Eϕ↑
M↓
Standard Train
A
w/o WF
0.897
0.860
0.958
0.019
0.939
0.916
0.979
0.006
0.928
0.926
0.984
0.010
B
w/o CPIM
0.887
0.843
0.950
0.023
0.934
0.910
0.974
0.007
0.921
0.917
0.981
0.012
C
CPIM w/o CA
0.887
0.845
0.953
0.021
0.935
0.909
0.914
0.006
0.919
0.911
0.979
0.012
D
w/o MRM
0.895
0.855
0.958
0.020
0.944
0.923
0.981
0.006
0.931
0.929
0.984
0.010
E
w/o Auxi-Tokens
0.891
0.846
0.952
0.022
0.943
0.921
0.982
0.006
0.931
0.928
0.983
0.010
TABLE IV: Unified ablation study under standard and joint training settings.
Fig. 4: Qualitative comparison of detection results on the VIAC (RGB-T) dataset.
Fig. 5: Visual ablation comparison of different variants.
Fig. 6: Attentional visualization of the transposed convolution branch within the SAM mask decoder.
Method
Params (M) ↓
Fβw↑
COD10K
PCOD-1200
VIAC
HQSAM
5.10
0.846
0.909
0.925
MM-SAM
93.73
0.808
0.801
0.906
COMPrompter
94.85
0.821
0.795
0.894
DSAM
121.93
0.760
0.839
0.440
SAM2-UNet
4.38
0.798
0.871
0.915
TABLE V: Comparison of trainable parameters and performance across three multi-modal COD benchmarks.
Methods
VT5000
VT1000
VT821
Sα↑
Fβw↑
Eϕ↑
M↓
Sα↑
Fβw↑
Eϕ↑
M↓
Sα↑
Fβw↑
Eϕ↑
M↓
HRTTransNet Tang et al. [2022]
0.945
0.912
0.870
0.025
0.945
0.938
0.913
0.017
0.929
0.906
0.849
0.026
WaveNet Zhou et al. [2023]
0.940
0.911
0.864
0.026
0.952
0.945
0.921
0.015
0.929
0.912
0.863
0.024
SACNet Wang et al. [2024a]
0.933
0.892
0.838
0.030
0.949
0.932
0.907
0.018
0.917
0.883
0.817
0.033
VSCode-v2 Luo et al. [2024]
0.931
-
0.962
-
0.952
-
0.984
-
0.932
-
0.958
-
UniSOD Wang et al. [2025b]
0.919
0.891
0.955
0.021
0.946
0.931
0.956
0.013
0.916
0.876
0.937
0.024
TABLE VI: Comparison of SOTA methods on multiple RGB-T SOD datasets. The best results are highlighted in bold .
Fig. 7: Qualitative comparison of detection results on RGB-T SOD datasets.
Train Modality
Test Modality
Sα↑
Eϕ↑
Fβw↑
M↓
RGB+D
RGB+P
0.924 (0.945)
0.968 (0.987)
0.890 (0.924)
0.010 (0.005)
RGB+D
RGB+T
0.916 (0.930)
0.976 (0.983)
0.908 (0.929)
0.013 (0.010)
RGB+DT
RGB+P
0.923 (0.945)
0.975 (0.987)
0.889 (0.924)
0.009 (0.005)
RGB+DP
RGB+T
0.920 (0.930)
0.978 (0.983)
0.915 (0.929)
0.012 (0.010)
TABLE VII: Quantitative comparison of cross-modality transfer experiments (parentheses denote matched-modality settings).
Fig. 8: Comparison under different challenging scenarios.
Camouflaged Object Detection (COD) aims to segment objects that are highly integrated with the background in terms of color, texture, and structure, making it a highly challenging task in computer vision. Although existing methods introduce multi-scale fusion and attention mechanisms to alleviate the above issues, they generally lack the guidance of textual semantic priors, which limits the model's ability to focus on camouflaged regions in complex scenes. To address this issue, this paper proposes a Language-Guided Structure-Aware Network (LGSAN). Specifically, based on the visual backbone PVT-v2, we introduce CLIP to generate masks from text prompts and RGB images, thereby guiding the multi-scale features extracted by PVT-v2 to focus on potential target regions. On this foundation, we further design a Fourier Edge Enhancement Module (FEEM), which integrates multi-scale features with high-frequency information in the frequency domain to extract edge enhancement features. Furthermore, we propose a Structure-Aware Attention Module (SAAM) to effectively enhance the model's perception of object structures and boundaries. Finally, we introduce a Coarse-Guided Local Refinement Module (CGLRM) to enhance fine-grained reconstruction and boundary integrity of camouflaged object regions. Extensive experiments demonstrate that our method consistently achieves highly competitive performance across multiple COD datasets, validating its effectiveness and robustness.
Min Zhang
School of Artificial Intelligence, Chongqing University of Technology, Chongqing, 401120, China
Video camouflaged object detection (VCOD) is challenging due to dynamic environments. Existing methods face two main issues: (1) SAM-based methods struggle to separate camouflaged object edges due to model freezing, and (2) MLLM-based methods suffer from poor object separability as large language models merge foreground and background. To address these issues, we propose a novel VCOD method based on SAM and MLLM, called Phantom-Insight. To enhance the separability of object edge details, we represent video sequences with temporal and spatial clues and perform feature fusion via LLM to increase information density. Next, multiple cues are generated through the dynamic foreground visual token scoring module and the prompt network to adaptively guide and fine-tune the SAM model, enabling it to adapt to subtle textures. To enhance the separability of objects and background, we propose a decoupled foreground-background learning strategy. By generating foreground and background cues separately and performing decoupled training, the visual token can effectively integrate foreground and background information independently, enabling SAM to more accurately segment camouflaged objects in the video. Experiments on the MoCA-Mask dataset show that Phantom-Insight achieves state-of-the-art performance across various metrics. Additionally, its ability to detect unseen camouflaged objects on the CAD2016 dataset highlights its strong generalization ability.
Hua Zhang, Changjiang Luo
Institute of Information Engineering, Chinese Academy of Sciences · School of Cyber Security, University of Chinese Academy of Sciences
Camouflaged Object Detection (COD) aims to identify and segment camouflaged objects in complex environments, which are often concealed because their color and texture are similar to the background. Several existing COD methods introduce depth maps to boost detection performance via learning complementary RGB-D features, ignoring modality-specific characteristics of concealed objects in the depth domain. To address this issue, we propose a depth collaborative network, called VCP-DCN, to mine distinguishable multi-modality features beyond visual concealed prototype in depth domain. Specifically, VCP-DCN progressively performs multi-modality alignment, interaction, and fusion for the COD task. In the alignment stage, we propose a Separable Prototype Embedding (SPE) module to learn modality-consistency and modality-specific RGB/depth prototype tokens through prototype contrastive learning. Furthermore, we develop a Multi-modality Dual Attention (MDA) module to enhance the cross-modal feature representation through local response maps between modality-consistency RGB/depth prototype tokens and visual tokens on the interaction stage. Finally, we design a Depth Adaptive Injection (DAI) module to adaptively measure contribution of RGB/depth features with a decision-making mechanism, which calculates similarity distance between RGB/depth modality-specific prototype tokens and modality-consistency ones on the fusion stage. Extensive experiments demonstrate the effectiveness of our VCP-DCN on three authoritative datasets.
Songsong Duan, Xi Yang, Nannan Wang
the State Key Laboratory of Integrated Services Networks, School of Telecommunications Engineering, Xidian University, Xi’an, China