Modified very deep super resolution network - Gaussian mixture models based single image super-resolution: A comprehensive comparative analysis

Image Super-Resolution (SISR) is a vital, cost-effective solution for enhancing the spatial resolution of satellite imagery. However, a significant challenge in current SISR techniques is that while deep learning models excel at structural learning, they often struggle to accurately reconstruct intricate high-frequency details and preserve the statistical texture properties of high-resolution images. To address this gap, this paper proposes a novel hybrid method, termed mVDSR-GMM, which leverages the complementary strengths of Gaussian Mixture Models (GMM) and a modified Very Deep Super-Resolution (mVDSR) network. GMM is utilized to model the underlying statistical and probabilistic properties of the image for accurate high-frequency reconstruction while the mVDSR network enhanced with 25 convolutional layers and Leaky ReLU activations boosts the model’s structural feature extraction and non-linear mapping capabilities. This hybrid approach technically integrates the mVDSR and GMM through a parallel merging of their estimated residuals within the luminance channel, thereby enhancing the spatial reconstruction of satellite imagery. The enhanced mVDSR network, with increased depth and Leaky ReLU activation functions, further boosts the model's learning capability and robustness. Through extensive evaluations using satellite imagery datasets and metrics such as PSNR, SSIM, BRISQUE, MSE, UIQI, SAM, and FD, mVDSR-GMM consistently outperformed existing techniques, demonstrating its effectiveness in improving spatial resolution. Experimental results indicate that mVDSR-GMM outperforms main competitors such as SwinIR and SinSR across all evaluation metrics, providing a robust reconstruction performance that is further validated by improved accuracy in the binary separation of urban structures (buildings and roads) from natural environments. The proposed mVDSR-GMM emerges as a promising tool for advancing satellite imagery resolution, with potential applications in remote sensing and geospatial analysis.