Organizations: Institute of Applied Sciences and Intelligent Systems (ISASI), CNR, 73100 Lecce, Italy · Dept. of Engineering for Innovation, University of Salento, 73100 Lecce, Italy · VSC Laboratory, Department of Electronics and Automation, University of Biskra, Biskra, Algeria · Dept. of Computer Science and AI, University of the Basque Country (UPV/EHU), Spain · VSC Laboratory, Department of Electronics and Automation, University of Biskra, Algeria · Institut Galilée, Université Sorbonne Paris Nord, F-93430, Villetaneuse, France · Sorbonne Center for Artificial Intelligence, Sorbonne University Abu Dhabi, Abu Dhabi, UAE
Accurate classification of hyperspectral imagery (HSI) is often frustrated by the tension between high-dimensional spectral data and the extreme scarcity of labeled training samples. While hierarchical models like LoLA-SpecViT have demonstrated the power of local windowed attention and parameter-efficient fine-tuning, the quadratic complexity of standard Transformers remains a barrier to scaling. We introduce VP-Hype, a framework that rethinks HSI classification by unifying the linear-time efficiency of State-Space Models (SSMs) with the relational modeling of Transformers in a novel hybrid architecture. Building on a robust 3D-CNN spectral front-end, VP-Hype replaces conventional attention blocks with a Hybrid Mamba-Transformer backbone to capture long-range dependencies with significantly reduced computational overhead. Furthermore, we address the label-scarcity problem by integrating dual-modal Visual and Textual Prompts that provide context-aware guidance for the feature extraction process. Our experimental evaluation demonstrates that VP-Hype establishes a new state of the art in low-data regimes. Specifically, with a training sample distribution of only 2%, the model achieves Overall Accuracy (OA) of 99.69% on the Salinas dataset and 99.45% on the Longkou dataset. These results suggest that the convergence of hybrid sequence modeling and multi-modal prompting provides a robust path forward for high-performance, sample-efficient remote sensing.
Figures & tables
Figure 1: Comparison of performance metrics across nine hyperspectral image (HSI) classification models. All scores are normalized relative to the proposed VP-Hype, which demonstrates superior performance across all datasets (IP, UP, SA, LK, HH, HC), overall accuracy metrics (AA, Kappa), and computational efficiency.
Figure 2: Architecture of the proposed VP-Hype framework. The model combines a hybrid Mamba–Transformer backbone with visual–textual prompting for hyperspectral image classification. Task-specific text prompts encoded by CLIP and learnable visual prompts are fused via Text Conditional Spatial Prompt (TCSP) blocks and injected at multiple network stages. The prompt-enhanced features are progressively downsampled and finally passed to a classification head for prediction.
Figure 3: Visualization of hyperspectral data cubes and corresponding ground-truth classification maps for the WHU - Hi - HongH, WHU - Hi - Longkou, and Salinas datasets: (a) hyperspectral image cube; (b) ground - truth map.
Metric
Ours
HSIMAE
HybridSN
ViT
MASSFormer
DBCT
LSGA
OA (%)
99.64
96.24
96.76
96.76
98.14
99.14
99.02
AA (%)
99.23
92.99
92.50
92.50
96.25
98.07
97.54
Kappa (%)
99.55
96.18
96.77
96.77
97.65
98.91
98.75
Table 1: Overall performance comparison on the HongHu dataset (10% training samples).
Metric
Ours
LoLA
MADANet
A 2 MFE
HybridSN
SSFTT
HiT
LANet
OA (%)
99.99
99.87
99.17
98.56
97.05
98.61
97.83
96.67
AA (%)
99.99
99.71
99.12
98.72
97.52
98.97
98.87
97.12
Kappa (%)
99.99
99.49
98.34
97.35
96.72
98.46
97.58
96.39
Table 2: Overall performance comparison on the Salinas dataset (10% training samples).
Metrics
Ours
Cross
Hybrid-ViT
Hir-Trans.
SSMamba
MorpMamba
E-SR-SSIM
LOLA
OA (%)
99.95
99.78
99.75
99.68
99.51
99.70
94.43
99.92
AA (%)
99.83
99.45
99.36
99.14
98.45
99.25
81.78
99.73
Kappa (%)
99.81
99.78
99.68
99.59
99.36
99.61
92.63
99.89
Table 3: Overall, average, and kappa accuracies (%) on the Longkou dataset (10% training samples).
Class
ViT
PiT
HiT
GAHT
AMHFN
Ours
1
89.7
89.4
89.8
95.9
95.9
99.99
2
63.6
87.4
90.2
94.8
95.3
98.82
3
75.1
48.2
88.0
94.4
96.2
98.99
4
90.1
89.6
90.6
95.6
96.3
99.84
5
79.0
76.8
91.6
95.8
94.5
98.48
6
96.4
95.5
96.1
97.9
98.1
99.82
Table 4: Classification accuracy (%) on Longkou dataset (2% training). Best results in bold.
Dataset
Train %
OA (%)
AA (%)
Kappa (%)
Longkou
2
99.45
99.20
99.28
Salinas
2
99.69
99.78
99.65
QUH-Qingyun
10
99.34
99.18
99.13
Table 5: MambaVision-T performance across three datasets with limited training samples.
Dataset
Configuration
Visual
Text
Prompt
OA (%)
AA (%)
Kappa (%)
Longkou
Visual-Only
✓
✗
✓
99.14
97.23
98.88
Text-Only
✗
✓
✓
98.30
99.00
98.10
No Prompt
✓
✓
✗
99.26
97.55
99.02
Full Model (Ours)
✓
✓
✓
99.45
99.20
99.28
Salinas
Visual-Only
✓
✗
✓
98.35
99.03
98.16
Text-Only
✗
✓
✓
98.30
99.00
98.10
Table 6: Ablation Study Results with 2% Training Samples
Dataset
Configuration
Visual
Text
Prompt
OA (%)
AA (%)
Kappa (%)
Longkou
Visual-Only
✓
✗
✓
99.52
99.47
99.46
Text-Only
✗
✓
✓
99.59
99.37
99.13
No Prompt
✓
✓
✗
99.24
99.18
99.09
Full Model (Ours)
✓
✓
✓
99.72
99.59
99.66
Salinas
Visual-Only
✓
✗
✓
99.84
99.82
99.82
Text-Only
✗
✓
✓
99.75
99.76
99.72
Table 7: Ablation Study Results with 10% Training Samples
Figure 4: Comparative classification performance on standard hyperspectral benchmarks: (I) Salinas, (II) WHU-Hi-LongKou, and (III) WHU-Hi-HongHu datasets. Ground truth and method predictions are presented with challenging regions highlighted (red boxes).
Textual Prompts
Visual Prompts
OA (%)
AA (%)
Kappa (%)
None (Baseline)
None
98.28
99.05
98.08
4 Prompts
None
99.31
99.54
99.23
None
4 Prompts
98.82
99.31
98.68
2 Prompts
2 Prompts
99.43
99.60
99.36
4 Prompts
4 Prompts
99.69
99.78
99.65
Table 8: Ablation study on the influence of the number of textual and visual prompts on VP-Hype performance (Salinas Dataset, 2% training samples).
Appendix figures & tables3 assets
Supplementary material from the paper’s appendix.
Appendix
Model
Dataset / Setting
Params (M)
Madanet [ 12 ]
Salinas
0.16
LANet [ 13 ]
Salinas
5.3
PiT-B [ 42 ]
Longkou (2%)
73.8
ViT-Huge [ 43 ]
Longkou (2%)
632.0
VP-Hype (ours)
All datasets
77.30
Appendix
Table B.1: Parameter counts of representative models, comparing compact CNNs, large-scale transformers, and the proposed VP-Hype, which achieves a favourable balance between model expressivity and computational footprint.
Class
Ours
LoLA
MADANet
A 2 MFE
HybridSN
SSFTT
HiT
LANet
OA (%)
99.99
99.87
99.17
98.56
97.05
98.61
97.83
96.67
AA (%)
99.99
99.71
99.12
98.72
97.52
98.97
98.87
97.12
Kappa (%)
99.99
99.49
98.34
97.35
96.72
98.46
97.58
96.39
Brocoli green weeds 1
100.00
100.00
99.64
99.46
99.30
99.34
100.00
98.32
Brocoli green weeds 2
100.00
100.00
98.95
97.28
99.96
100.00
99.75
98.64
Fallow
100.00
100.00
98.90
97.99
98.16
99.89
100.00
95.09
Appendix
Table B.2: Overall, average, kappa, and per-class accuracies (%) on the Salinas dataset (10% training samples).
Class
Ours
HSIMAE
HybridSN
ViT
MASSFormer
DBCT
LSGA
OA (%)
99.64
96.24
96.76
96.76
98.14
99.14
99.02
AA (%)
99.23
92.99
92.50
92.50
96.25
98.07
97.54
Kappa (%)
99.55
96.18
96.77
96.77
97.65
98.91
98.75
Red roof
99.84
97.40
98.46
97.84
98.99
98.27
99.54
Road
99.71
88.87
75.45
87.22
97.25
97.44
96.82
Bare soil
99.59
95.84
95.61
94.98
98.87
99.01
98.23
Appendix
Table B.3: Overall, average, kappa, and per-class accuracies (%) on the HongHu dataset (10% training samples).
Hyperspectral image (HSI) classification remains challenging due to high spectral dimensionality, redundancy, and limited labeled data. Although convolutional neural networks (CNNs) and Vision Transformers (ViTs) achieve strong performance by exploiting spectral-spatial information and long-range dependencies, they often incur high computational cost and large model size, limiting practical use. To address these limitations, a unified hybrid framework, termed ConvVitMamba, is proposed for efficient HSI classification. The architecture integrates three components: a multiscale convolutional feature extractor to capture local spectral, spatial, and joint patterns; a Vision Transformer based tokenization and encoding stage to model global contextual relationships; and a lightweight Mamba inspired gated sequence mixing module for efficient content-aware refinement without quadratic self-attention. Principal Component Analysis (PCA) is used as preprocessing to reduce redundancy and improve efficiency. Experiments on four benchmark datasets, including Houston and three UAV borne QUH datasets (Pingan, Qingyun, and Tangdaowan), demonstrate that ConvVitMamba consistently outperforms CNN, Transformer, and Mamba based methods while maintaining a favorable balance between accuracy, model size, and inference efficiency. Ablation studies confirm the complementary contributions of all components. The results indicate that the proposed framework provides an effective and efficient solution for HSI classification in diverse scenarios. The source code is publicly available at https://github.com/mqalkhatib/ConvVitMamba
Mohammed Q. Alkhatib
College of Engineering and IT, University of Dubai, Dubai 14143, United Arab Emirates
Hyperspectral imaging enables fine-grained recognition of materials by capturing rich spectral signatures, but learning robust classifiers is challenging due to high dimensionality, spectral redundancy, limited labeled data, and strong domain shifts. Beyond earth observation, labeled HSI data is often scarce and imbalanced, motivating compact models for generic hyperspectral classification across diverse acquisition regimes. We propose the lightweight Spectral-Spatial Fusion Transformer (SSFT), which factorizes representation learning into spectral and spatial pathways and integrates them via cross-attention to capture complementary wavelength-dependent and structural information. We evaluate our SSFT on the challenging HSI-Benchmark, a heterogeneous multi-dataset benchmark covering earth observation, fruit condition assessment, and fine-grained material recognition. SSFT achieves state-of-the-art overall performance, ranking first while using less than 2% of the parameters of the previous leading method. We further evaluate transfer to the substantially larger SpectralEarth benchmark under the official protocol, where SSFT remains competitive despite its compact size. Ablation studies show that both spectral and spatial pathways are crucial, with spatial modeling contributing most, and that SSFT remains robust without data augmentation.
Alexander Musiat, Nikolas Ebert, Oliver Wasenmüller
In the hyperspectral image (HSI) classification task, each pixel is categorized into a specific land-cover category or material. Convolutional neural networks (CNNs) and transformers have been widely used to extract local and non-local features in HSI classification. Recent works have utilized a multi-scale vision transformer (ViT) to enhance spectral feature capture and yield promising results. However, most existing methods still face challenges in the effective joint use of spatial-spectral information and in preserving information across layers during the propagation process. To address these issues, we propose a synergistic CNN-Transformer network with pooling attention fusion for HSI classification, which collaboratively utilizes CNNs and ViT to process spatial and spectral features separately. Specifically, we propose a Twin-Branch Feature Extraction (TBFE) module, which employs 3D and 2D convolution in parallel to comprehensively extract spectral and spatial features from HSI. A hybrid pooling attention (HPA) module is designed to aggregate spatial attention. Moreover, a cascade transformer encoder is employed for global spectral feature extraction, and a simple yet efficient cross-layer feature fusion (CFF) module is designed to reduce the loss of crucial information in the previous network layers. Extensive experiments are conducted on several representative datasets to demonstrate the superior performance of our proposed method compared to the state-of-the-art works. Code is available at https://github.com/chenpeng052/SCT-Net.git.
Peng Chen, Wenxuan He, Feng Qian +2
College of Engineering, Shantou University, Shantou, 515063, Guangdong, China · School of Electronic Information and Communications, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China · Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, Jilin, China +2