A New Single-Image Super-Resolution Using Efficient Feature Fusion and Patch Similarity in Non-Euclidean Space

Efficient trade-off between the reconstruction qualities and the processing time of any single-image super-resolution reconstruction (SISRR) approach is critically influenced by two major aspects. These aspects are (i) appropriate representation of image patch in feature space and (ii) effective searching of candidate patches from the pool of training patches or learned dictionary. This paper proposes a neighbor embedding-based SISRR method. Novelties of our work include integration of (i) efficient feature mapping scheme which fuses multiple correlated features naturally, (ii) faster searching of candidate patches by measuring the patch correlation in non-Euclidean space and (iii) adaptive selection of neighborhood size using patch characteristic. Correlation among features is modeled via global covariance matrix, and the fusion process enables to preserve sufficient structural, spatial correlation among patches. Distance functions based on notion of generalized eigenvalue are used for measuring patch similarity which support faster searching of candidate patches. Performance analysis of the suggested method is compared with some of the competent state-of-the-art methodologies. From the simulated result analysis, proposed work is found to be outperforming in terms of sharpened image details with diminished effect of artifacts at a reasonable computational burden.