Super-resolution reconstruction of hypertemporal remote sensing images based on self-attention
Video satellite hypertemporal data have the characteristics of high temporal resolution,while the single-frame super-resolution reconstruction algorithm can only use the information of the image frame itself,and the reconstruction effect is limited.Therefore,how to utilize fully and effectively the rich spatiotemporal information in hypertemporal data in the super-resolution reconstruction of video satellite images is an issue of interest.Aiming at the characteristics of hypertemporal data,this study proposes a self-attention-based super-resolution reconstruction model of hypertemporal remote sensing images.The model can mine high-frequency information from low-resolution images through an end-to-end network.High-resolution images are recovered from multiple frames of low-resolution images.First,the hypertemporal sequence frames are divided into multiple time groups according to the frame rate,and the spatial and temporal information under different time groups are extracted by using the characteristics of 3D convolution to model space and time simultaneously.It pays attention to the calculation range and completes high dynamic mapping,extracts rich spatial detail information while realizing hypertemporal sequence frame modeling,and finally fuses the features of multiple time groups and completes the reconstruction through subpixel convolution to improve the resolution.The advantage of the proposed algorithm is that the multitime group feature fusion method can extract the spatiotemporal information of sequence frames in multiple time dimensions and fully mine the rich spatiotemporal-related information in the hypertemporal data;the improved self-attention block can be used without registration.It can complete the modeling of sequence frames and improve the extraction ability of detailed spatial information.Experiments on the GF-4 dataset show that the subjective visual effect and objective evaluation index of the algorithm are better than those of the comparison algorithm.When the GF-4 dataset is reconstructed twice,the PSNR value is improved by more than 2.49 dB compared with the bicubic interpolation algorithm,and it still has a strong reconstruction performance when the reconstruction is four times,which is a huge improvement compared with the bicubic interpolation algorithm.Experimental results show that the method has good super-resolution reconstruction effect,which is beneficial to the application of hypertemporal data in various fields.The self-attention-based super-resolution model of hypertemporal remote sensing images proposed in this study fully extracts the spatiotemporal information in hypertemporal data by dividing multiple time groups and calculating the attention features in each time group.The combination of multitemporal group feature fusion and self-attention enables the modeling of overphase sequence frames while ensuring the ability to extract detailed information.Comparative experiments on the GF-4 dataset show that the algorithm in this study is superior to the compared algorithm in terms of objective evaluation indicators and subjective visual effects,verifying the effectiveness and advancement of the algorithm in super-resolution reconstruction of hypertemporal data and the algorithm's improved reconstruction performance.However,the proposed algorithm must be optimized in terms of calculation time.In a follow-up research,the algorithm structure will be optimized(e.g.,changing the residual structure of the network)to reduce the calculation time while ensuring accuracy.
remote sensinghyper-temporal datasuper-resolution reconstructiondeep learningfusion feature of multiple time groupswide self-attentionGF-4