Deep learning approaches have contributed to the rapid development of Remote Sensing (RS) image interpretation. The most widely used training paradigm is to utilize ImageNet pre-trained models to process RS data for specified tasks. However, there are issues such as domain gap between natural and RS scenes, and the poor generalization capacity of RS models. It makes sense to develop a foundation model with general RS feature representation. Since a large amount of unlabeled data is available, the self-supervised method has more development significance than the fully supervised method in remote sensing. However, most of the current self-supervised methods use contrastive learning, whose performance is sensitive to data augmentation, additional information, and selection of positive and negative pairs. In this paper, we leverage the benefits of generative self-supervised learning for RS images, and propose a Remote sensing foundation Model framework called RingMo, which consists of two parts. First, a large-scale dataset is constructed by collecting two million RS images from satellite and aerial platforms, covering multiple scenes and objects around the world. Second, we propose an RS foundation model training method designed for dense and small objects in complicated RS scenes. We show that the foundation model trained on our dataset with RingMo method achieves state-of-the-art on eight datasets across four downstream tasks, demonstrating the effectiveness of the proposed framework. Through in-depth exploration, we believe it is time for RS researchers to embrace generative self-supervised learning and leverage its general representation capabilities to speed up the development of RS applications.
5 January 2021 in IEEE Transactions on Geoscience and Remote Sensing
In recent years, deep convolutional neural networks (DCNNs) have made significant progress in cloud detection tasks, and the detection accuracy has been greatly improved. However, most existing CNN-based models have high computational complexity, which limits their practical application, especially for spaceborne optical remote sensing. In addition, most of the methods cannot make adaptive adjustments based on the structural information of the clouds, and blurred boundaries often occur in the detection results. In order to address these problems, this article proposes a lightweight network (DABNet) to achieve high-accuracy detection of complex clouds, not only a clearer boundary but also lower false-alarm rate. Specifically, a deformable context feature pyramid module is proposed to improve the adaptive modeling capability of multiscale features. Besides, a boundary-weighted loss function is designed to direct the network to focus on cloud boundary information and optimize the relevant detection results. The proposed method has been validated on two data sets: the public GF-1 WFV benchmark and our self-built GF-2 cloud detection data set with higher spatial resolution. The experimental results exhibit that DABNet achieves state-of-the-art performance while only using 4.12M parameters and 8.29G multiadds.
16 February 2022 in IEEE Transactions on Geoscience and Remote Sensing
Recently, satellite video has become an emerging means of earth observation, providing the possibility of tracking moving objects. However, the existing multi-object trackers are commonly designed for natural scenes without considering the characteristics of remotely sensed data. In addition, most trackers are composed of two independent stages of detection and reidentification (ReID), which means that they cannot be mutually promoted. To this end, we propose an end-to-end online framework, which is called TGraM, for multi-object tracking in satellite videos. It models multi-object tracking as a graph information reasoning procedure from the multitask learning perspective. Specifically, a graph-based spatiotemporal reasoning module is presented to mine the potential high-order correlations between video frames. Furthermore, considering the inconsistency of optimization objectives between detection and ReID, a multitask gradient adversarial learning strategy is designed to regularize each task-specific network. In addition, aiming at the data scarcity in this field, a large-scale and high-resolution Jilin-1 satellite video dataset for multi-object tracking (AIR-MOT) is built for the experiments. Compared with state-of-the-art multi-object trackers, TGraM achieves efficient collaborative learning between detection and ReID, improving the tracking accuracy by 1.2 multiple object tracking accuracy. The code and dataset will be available online ( https://github.com/HeQibin/TGraM ).
With the advancement of global civilisation, monitoring and managing dumpsites have become essential parts of environmental governance in various countries. Dumpsite locations are difficult to obtain in a timely manner by local government agencies and environmental groups. The World Bank shows that governments need to spend massive labour and economic costs to collect illegal dumpsites to implement management. Here we show that applying novel deep convolutional networks to high-resolution satellite images can provide an effective, efficient, and low-cost method to detect dumpsites. In sampled areas of 28 cities around the world, our model detects nearly 1000 dumpsites that appeared around 2021. This approach reduces the investigation time by more than 96.8% compared with the manual method. With this novel and powerful methodology, it is now capable of analysing the relationship between dumpsites and various social attributes on a global scale, temporally and spatially.
22 February 2023 in IEEE Transactions on Image Processing
Multi-modal remote sensing (RS) image segmentation aims to comprehensively utilize multiple RS modalities to assign pixel-level semantics to the studied scenes, which can provide a new perspective for global city understanding. Multi-modal segmentation inevitably encounters the challenge of modeling intra- and inter-modal relationships, i.e. , object diversity and modal gaps. However, the previous methods are usually designed for a single RS modality, limited by the noisy collection environment and poor discrimination information. Neuropsychology and neuroanatomy confirm that the human brain performs the guiding perception and integrative cognition of multi-modal semantics through intuitive reasoning. Therefore, establishing a semantic understanding framework inspired by intuition to realize multi-modal RS segmentation becomes the main motivation of this work. Drived by the superiority of hypergraphs in modeling high-order relationships, we propose an intuition-inspired hypergraph network ( I 2 HN ) for multi-modal RS segmentation. Specifically, we present a hypergraph parser to imitate guiding perception to learn intra-modal object-wise relationships. It parses the input modality into irregular hypergraphs to mine semantic clues and generate robust mono-modal representations. In addition, we also design a hypergraph matcher to dynamically update the hypergraph structure from the explicit correspondence of visual concepts, similar to integrative cognition, to improve cross-modal compatibility when fusing multi-modal features. Extensive experiments on two multi-modal RS datasets show that the proposed I 2 HN outperforms the state-of-the-art models, achieving F 1 /mIoU accuracy 91.4%/82.9% on the ISPRS Vaihingen dataset, and 92.1%/84.2% on the MSAW dataset. The complete algorithm and benchmark results will be available online.
15 September 2022 in ISPRS Journal of Photogrammetry and Remote Sensing