Improved fast new edge-directed fractional interpolation algorithm

Abstract

The original New Edge-Directed Interpolation(NEDI) algorithm is of high complexity,difficult for hardware implementation,and the interpolated images may suffer from blurring edges around edge area.To achieve a better subjective quality,an improved NEDI algorithm was proposed in this paper.In the new algorithm,a circular window was adopted,and the interpolation coefficient calculation was calculated only once,which could be reused in interpolating the center-pixels,thus the errors introduced by iterative computation were avoided and the interpolation time was saved.As to non-center pixels,six original neighbors were involved to estimate local covariance characteristics at high resolution.In comparison with the results of bi-cubic interpolation and the traditional NEDI,the experimental results indicate that proposed algorithm can eliminate the sawtooth of the interpolated picture in large-scale,and decrease the computational complexity.