Convolutional autoencoder pan-sharpening method for spectral indices in landsat 8 images

Pan-sharpening (PS) consists of combining a high spatial resolution (HR) panchromatic image (PAN) and a low spatial resolution (LR) multispectral image (MS) to generate an MS-HR image. However, some PS methods have spectral and spatial distortions that influence subsequent analyses. Thus, this study aimed to develop a PS method based on convolutional autoencoder (CAE) for Landsat 8 images and evaluate its performance in calculating spectral indices. In the PS process, we trained a CAE network and used a multiscale-guided filter. The performance of the proposed method was analyzed using the Kolmogorov-Smirnov (K-S) statistic of the empirical cumulative distribution function (eCDF) between the values of the Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), and Normalized Difference Moisture Index (NDMI) of the PS and MS-LR images. The results show that the proposed method is effective for calculating the indices. Therefore, we conclude that it has great potential for preserving the spatial information of the PAN image and the spectral information of the MS-LR image during the PS process for calculating spectral indices.