Camouflaged object detection (COD) aims to discover objects that blend in with the background due to similar colors or textures, etc. Existing deep learning methods do not systematically illustrate the key tasks in COD, which seriously hinders the improvement of its performance. In this paper, we introduce the concept of focus areas that represent some regions containing discernable colors or textures, and develop a two-stage focus scanning network for camouflaged object detection. Specifically, a novel encoder-decoder module is first designed to determine a region where the focus areas may appear. In this process, a multi-layer Swin transformer is deployed to encode global context information between the object and the background, and a novel cross-connection decoder is proposed to fuse cross-layer textures or semantics. Then, we utilize the multi-scale dilated convolution to obtain discriminative features with different scales in focus areas. Meanwhile, the dynamic difficulty aware loss is designed to guide the network paying more attention to structural details. Extensive experimental results on the benchmarks, including CAMO, CHAMELEON, COD10K, and NC4K, illustrate that the proposed method performs favorably against other state-of-the-art methods.

Hyperspectral image (HSI) classification methods have made great progress in recent years. However, most of these methods are rooted in the closed-set assumption that the class distribution in the training and testing stages is consistent, which cannot handle the unknown class in open-world scenes. In this work, we propose a feature consistency-based prototype network (FCPN) for open-set HSI classification, which is composed of three steps. First, a three-layer convolutional network is designed to extract the discriminative features, where a contrastive clustering module is introduced to enhance the discrimination. Then, the extracted features are used to construct a scalable prototype set. Finally, a prototype-guided open-set module (POSM) is proposed to identify the known samples and unknown samples. Extensive experiments reveal that our method achieves remarkable classification performance over other state-of-the-art classification techniques.

Oil spill mapping is a very challenging problem in marine environmental monitoring. In this article, the potential of hyperspectral image (HSI) classification for mapping oil spills is comprehensively investigated. First, several representative HSI classification methods are reviewed in a general framework. Second, three oil spill mapping cases are designed to analyze the performance of different classification methods in detecting spatial distribution, classifying the type, and estimating the thickness of oil spills. Finally, the experimental results are analyzed in detail, and some conclusions are given, which brings a comprehensive understanding to scholars who are interested in the fields of hyperspectral remote sensing and oil spill mapping.

Hyperspectral oil spill mapping aims to distinguish the type of oil spill. Recently, most hyperspectral oil spill detection methods are based on supervised methods that work well with rich training samples. However, in the marine oil spill detection scenario, pixel annotations are difficult and costly. Moreover, the labels obtained by domain experts within a hyperspectral image (HSI) are often scarce. To address these issues, a self-supervised spectral-spatial transformer network is proposed for hyperspectral oil spill mapping. First, we propose a transformer-based contrastive learning network to extract the deep discriminative features. Then, the learned features are transferred to the downstream classification network that is fine-tuned with very few labeled samples. Experiments on hyperspectral oil spill database (HOSD) constructed by ourselves indicate that the proposed method can obtain more promising performance than several state-of-the-art oil spill classification techniques in discriminating different types of oil spills, i.e., thick oil, thin oil, sheen, and seawater.

In recent years, deep-learning-based pixel-level unified image fusion methods have received more and more attention due to their practicality and robustness. However, they usually require a complex network to achieve more effective fusion, leading to high computational cost. To achieve more efficient and accurate image fusion, a lightweight pixel-level unified image fusion (L-PUIF) network is proposed. Specifically, the information refinement and measurement process are used to extract the gradient and intensity information and enhance the feature extraction capability of the network. In addition, these information are converted into weights to guide the loss function adaptively. Thus, more effective image fusion can be achieved while ensuring the lightweight of the network. Extensive experiments have been conducted on four public image fusion datasets across multimodal fusion, multifocus fusion, and multiexposure fusion. Experimental results show that L-PUIF can achieve better fusion efficiency and has a greater visual effect compared with state-of-the-art methods. In addition, the practicability of L-PUIF in high-level computer vision tasks, i.e., object detection and image segmentation, has been verified.