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Real-Time Digital Auto-Focusing Using A-Priori Estimated Point Spread Functions  

Yoo Yoon-Jong (Dept. Image Eng., Graduate School of Advanced Imaging Science, Multimedia and Film, Chung-Ang University)
Lee Jung-Soo (Dept. Image Eng., Graduate School of Advanced Imaging Science, Multimedia and Film, Chung-Ang University)
Shin Jeong-Ho (Dept. Web Information Engineering, Hankyoung National University)
Paik Joon-Ki (Dept. Web Information Engineering, Hankyoung National University)
Publication Information
Journal of the Institute of Electronics Engineers of Korea SP / v.43, no.5, 2006 , pp. 1-11 More about this Journal
Abstract
This paper presents a digital auto-focusing method using a priori estimated point-spread-functions (PSF) database. The proposed algorithm efficiently removes out-of-focus blur in a degraded input image by selecting the optimal PSF from the database. The database consists of optical characteristics of image formation system. The PSF selection Process is performed based on a novel focusing measure. The proposed method includes a spatially adaptive filter for removing both noise and ringing artifacts. Experimental results show that the proposed method efficiently removes out-of-focus blur using significantly reduced computational load compared with the existing method.
Keywords
디지털 자동초점;영상복원;점확산함수;링잉제거;
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Times Cited By KSCI : 1  (Citation Analysis)
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