Defocus blur parameters identification by histogram matching.

J Opt Soc Am A Opt Image Sci Vis

Department of Electrical Engineering and Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, 168 University Rd., Min-Hsiung, Chiayi 621, Taiwan.

Published: August 2012

A defocus blur identification technique based on histogram analysis of a real edge image is presented. The image defocus process of a camera is formulated by incorporating the nonlinear camera response and the intensity-dependent noise model. The histogram matching between the synthesized and real defocused regions is then carried out with intensity-dependent filtering. By iteratively changing the point-spread function parameters, the best blur extent is identified from histogram comparison. We have performed the experiments on both the synthetic and real edge images. The results have demonstrated the robustness and feasibility of the proposed technique.

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http://dx.doi.org/10.1364/JOSAA.29.001694DOI Listing

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