New adaptive filter and quality evaluation index for image restoration

This paper presents a new technique for image adaptive restoration called 3σ-multiresolution plane fitting (3σ-MPF) and the global restoration index (GRI) index, which evaluates the restoration performance of smoothing methods. The 3σ-MPF filter is based on an adaptive plane fitting technique using variable-sized windows with different behavior for continuous regions or discontinuities. The criteria used to select the window size and detect discontinuities is the 3σ-fidelity test. The GRI, integrates two independent indices measuring restoration smoothness and fidelity. Using this index, the 3σ-MPF filter performance is compared with other traditional methods, demonstrating better performance under Gaussian noise and robustness against outliers.