Publications

Chen, YJ; Zhou, DZ; Niu, J; Li, XK (2025). No-reference-image gap filling for Landsat-7 ETM + SLC-off images under unsupervised classification criteria. SIGNAL IMAGE AND VIDEO PROCESSING, 19(7), 518.

Abstract
This paper presents a filling method to restore the SLC-off images of the Landsat 7 satellite without using reference images. Firstly, the preprocessing stage provides processing for gap localization, unsupervised classification, and local average greyscale calculation. Secondly, we conduct regression analysis to obtain the grey-level slope of the pixels on the two sides of the gap in vertical, 45 degrees and 135 degrees directions, and combine them with unsupervised classification results to decide the most likely filling direction for current missing pixel. We use a random strategy and cubic spline interpolation to fill edge pixels and non-edge pixels of the gaps. Finally, we utilize an adaptive filter to filter the gaps. The experimental results indicate that this method significantly outperforms other methods in terms of PSNR, SSIM, MAPE and FID. Our code will be available in GitHub depository at https://github.com/cheenyanjun/GapfillingLandsat-7norefer.

DOI:
10.1007/s11760-025-04168-7

ISSN:
1863-1711