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Applied Optics

Applied Optics


  • Vol. 41, Iss. 23 — Aug. 10, 2002
  • pp: 4806–4811

Digital restoration of defocused images in the wavelet domain

Edmund Y. Lam  »View Author Affiliations

Applied Optics, Vol. 41, Issue 23, pp. 4806-4811 (2002)

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Many cameras nowadays are equipped with an autofocus mechanism that attempts to take pictures at the best possible focus. However, there are situations in which the pictures are still out of focus, such as when the photographer has mistakenly focused at a wrong position or when the focusing region consists of objects of different depths and therefore confuses the autofocus system. With a digital camera, we can attempt to use digital image-restoration techniques to bring the pictures back into focus. We design an algorithm that restores the image by digitally enhancing the corresponding frequency bands. We employ the restoration in the wavelet domain so that this restoration scheme can be compliant with JPEG 2000, which is positioned to succeed JPEG as the next image-compression standard and has the potential to be widely adopted by the digital photography industry owing to its many advanced features.

© 2002 Optical Society of America

OCIS Codes
(100.3020) Image processing : Image reconstruction-restoration
(100.7410) Image processing : Wavelets
(110.5200) Imaging systems : Photography
(220.1000) Optical design and fabrication : Aberration compensation
(220.2560) Optical design and fabrication : Propagating methods

Original Manuscript: June 4, 2001
Revised Manuscript: April 29, 2002
Published: August 10, 2002

Edmund Y. Lam, "Digital restoration of defocused images in the wavelet domain," Appl. Opt. 41, 4806-4811 (2002)

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