Defocus Blur Parameter Estimation Technique

Abstract

De-blurring through blind image deconvolution requires deriving the blur kernel or point spread function (PSF) as it cannot be assumed. In case of defocus blur, the PSF or the degradation function can be represented through parametric expressions. Identification of the parameters is sufficient in these situations to formulate the PSF. In this paper, a technique to estimate defocus blur parameter is proposed. The approach is based on the relationship between the blur radius and the spectral features of defocus blurred image. The method proposed is aimed at finding the radius of the innermost circle among the concentric circles in the frequency spectrum of defocus blurred images. The proposed technique is tested on Berkeley and Pascal VOC datasets which displays around 98% defocus blur radius estimation accuracy for blur radius between 3 and 50.