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Inspite of technological advancement, inherent processing capability of current age sensors limits the desired details in the acquired image for variety of remote sensing applications. Pan-sharpening is a prominent scheme to integrate the essential spatial details inferred from panchromatic (PAN) image and the desired spectral information of multispectral (MS) image. This paper presents an effective two-stage pan-sharpening method to produce high resolution multispectral (HRMS) image. The proposed method is based on the premise that the HRMS image can be formulated as an amalgam of spectral and spatial components. The spectral components are estimated by processing the interpolated MS image with a filter approximated with modulation transfer function (MTF) of the sensor. Sparse representation theory is adapted to construct the spatial components. The high-frequency details extracted from the PAN image and its low resolution variant are utilized to construct dual dictionaries. The dictionaries are jointly learned by an efficient training algorithm to enhance the adaptability. The hypothesis of sparse coefficients invariance over scales is also incorporated to reckon the appropriate spatial information. Further, an iterative filtering mechanism is developed to enhance the quality of fused image. Four distinct datasets generated from QuickBird, IKONOS, Pléiades and WorldView-2 sensors are used for experimentation. The comprehensive assessment at reduced-scale and full-scale persuade the effectiveness of proposed method in the retention of spectral information and intensification of the spatial details.

The optical satellite sensors encounter certain constraints on producing high-resolution multispectral (HRMS) images. Pan-sharpening (PS) is a remote sensing image fusion technique, which is an effective mechanism to overcome the limitations of available imaging products. The prevalent issue in PS algorithms is the imbalance between spatial quality and spectral details preservation, thereby producing intensity variations in the fused image. In this paper, a PS method is proposed based on convolutional sparse coding (CSC) implemented in the non-subsampled shearlet transform (NSST) domain. The source images, panchromatic (PAN) and multispectral (MS) images, are decomposed using NSST. The resultant high-frequency bands are fused using adaptive weights determined from chaotic grey wolf optimization (CGWO) algorithm. The CSC-based model is employed to fuse the low-frequency bands. Further, an iterative filtering mechanism is developed to enhance the quality of fused image. Four datasets with different geographical content like urban area, vegetation, etc. and eight existing algorithms are used for evaluation of the proposed PS method. The comprehensive visual and quantitative results approve that the proposed method accomplishes considerable improvement in spatial and spectral details equivalence in the pan-sharpened image.

Pan-sharpening is a procedure to fuse the spatial detail of high-resolution multispectral images (HR-MSI) and low-resolution hyperspectral images (LR-HSI) to produce HR-MSI. Due to increase in high-resolution satellites, methods based on pan-sharpening are increasingly utilized all over the world. However, the majority of techniques consider pan-sharpening as a major issue, which hinders the discriminative ability. This work proposes an optimization-based deep model for pan-sharpening using LR-HSI and HR-MSI. Initially, the LR-HSI is input into an up-sampling mode, and the resulting image is fed into weighted linear regression. Concurrently, HR-MSI is supplied into weighted linear regression. Weighted linear regression is used to combine the upsampled LR-HSI and HR-MSI. The HR-MSI is then sent into the Deep Maxout network (DMN), which learns the priors via residual learning. Furthermore, the suggested Competitive Multi-Verse Feedback Artificial Tree (CMVFTA) strategy is used for DMN training, which is constructed by combining the Competitive Multi-Verse Optimizer (CMVO) and Feedback Artificial Tree (FAT) approaches. Finally, the DMN, LR-HSI, and HR-MSI outputs are merged together to provide a pan-sharpening image. The proposed CMVFTA-based DMN offered enhanced performance with Degree of Distortion (DD) of 0.0402 dB, Peak signal-to-noise ratio (PSNR) of 49.60 dB, Root Mean Squared Error (RMSE) of 0.330, Relative Average Spectral Error (RASE) of 0.322, Filtered Correlation Coefficients (FCC) of 0.874, Quality with no reference (QNR) of 76.19.