PGCS: Physical Law Embedded Generative Cloud Synthesis in Remote Sensing Images

Data quantity and quality are both critical for information extraction and analyzation in remote sensing. The current remote sensing datasets, however, often fail to meet these two requirements, for which the cloud is a primary factor degrading the data quantity and quality. This limitation affects the precision of results in remote sensing applications, particularly those derived from data-driven techniques. In this article, a physical law embedded generative cloud synthesis (PGCS) method is proposed to generate diverse,ealistic cloud images to enhance real data and promote the development of algorithms for subsequent tasks, such as cloud correction, cloud detection, and data augmentation for classification, recognition, and segmentation. The PGCS method involves two key phases: spatial synthesis and spectral synthesis. In the spatial synthesis phase, a style-based generative adversarial network is used to simulate the spatial characteristics, generating an infinite number of single-channel clouds. In the spectral synthesis phase, the atmospheric scattering law is embedded through a local statistics and global fitting method, converting the single-channel clouds into multispectral clouds. The experimental results demonstrate that PGCS achieves a high accuracy in both phases and performs better than three other existing cloud synthesis methods. Two cloud correction methods are developed from PGCS and exhibits a superior performance compared to state-of-the-art methods in the cloud correction task. The application of PGCS with data from various sensors was, furthermore, investigated and successfully extended. Code will be provided at https://github.com/Liying-Xu/PGCS.