Remote sensing images usually reveal various objects with complex structures and different locations within vast ground area backgrounds. That leads to a major challenge for conventional generative models in handling remote sensing objects with correct shapes and clear textures. Integrating additional object-level controls can be a potential solution to improve generation quality, yet previous approaches inject the object-related conditions by specifying their locations, causing a limitation in object layout in generated results. To enable high object fidelity, high layout diversity and object customizable generation for remote sensing images, we propose a remote sensing image generation via object text decoupling, namely OTD-GAN. OTD-GAN takes advantage of the inherent text-to-image generation procedure and adaptively integrates the decoupled textual representations of visual objects into the global captions, thus achieving object-level controls without layout restrictions. Specifically, we design an object text decoupling module to predict a semantically consistent textual representation for each object. By decoupling the textual representation into a class invariant part and an object specific part, the converted representation is able to catch general semantic for similar objects as well as differentiated details for individual objects. After that, we use an object text semantic enhancement module to fuse the obtained object text representations with the global captions to enrich the object-related semantic within the textual modality. As a result, the generator will benefit from the object conditions and reinforce the generation quality while remaining flexibility to create diverse layouts. Extensive experiments on remote sensing image-caption datasets including NWPU-Captions and RSICD demonstrate that our method achieves leading performance compared to existing state-of-the-art approaches.

Low-resolution characteristics of multispectral images restrict their usability. Various approaches (e.g., single-image super-resolution reconstruction (SISR) and pansharpening method) have been proposed to enrich the spatial details of low-resolution multispectral images (LRMSs) to obtain high-resolution ones. While the pansharpening method inevitably depends on panchromatic (PAN) images, which limits its application scenarios, SISR does not need auxiliary images, yet the blurred edge details within the reconstructed super-resolution multispectral (SRMS) images still remain a big challenge. In this work, we propose a novel high-frequency feature transfer (HFFT-PAN) method for multispectral image super-resolution to tackle the above drawbacks. Specifically, we first exploit the inherent low-frequency features among LRMS images to facilitate the extraction of high-frequency features from PAN images. After that, the high-frequency features from PAN images are transferred to the reconstruction procedure of multispectral images so that the SRMS images can not only benefit from the edge detail information from PAN images but also avoid the utilization of any PAN images during inference. Moreover, we employ an additional contrastive loss during training to ensure the fidelity of the generated SRMS images. Qualitative and quantitative evaluations exhibit that the proposed method performs favorably against state-of-the-art methods. The model and code are available athttps://github.com/wx0110wx/HFFT.

Long-tailed distribution of remote sensing data generally limits the object recognition performance of deep neural networks. We notice that too many samples from head class will induce the neural network to learn features of tail class samples being biased towards the head. To solve this, we propose a novel center-wise feature consistency learning (CFCL) mechanism for long-tailed remote sensing object recognition. Firstly, we implement a head-tail center feature generation procedure that builds two teacher models to extract the knowledge from the head class and tail class samples respectively, so as to avoid the extracted tail class features being affected by the head classes. Secondly, a center-wise feature consistency learning strategy is introduced, which distills the central feature of each class to a student model, thereby making the classification boundaries more prominent. Especially, the central feature is estimated by referring to the features which are correctly classified by the teacher models, thus the inaccurate knowledge is abandoned. Extensive experiments on widely-adopted remote sensing recognition datasets including FGSC-23, DIOR, xView and HRSC2016 demonstrate that our method achieves superior performance compared to the state-of-the-art approaches.Code and data are available at: https://github.com/wdzhao123/CWFC.