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Optics Letters

Optics Letters


  • Editor: Alan E. Willner
  • Vol. 35, Iss. 8 — Apr. 15, 2010
  • pp: 1272–1274

Focus measure based on the energy of high-frequency components in the S transform

Muhammad Tariq Mahmood and Tae-Sun Choi  »View Author Affiliations

Optics Letters, Vol. 35, Issue 8, pp. 1272-1274 (2010)

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Focus measure plays a fundamental role in the shape from focus technique. In this Letter, we suggest a focus measure in the S-transform domain that is based on the energy of high-frequency components. A localized spectrum by using variable window size provides a more accurate method of measuring image sharpness as compared to other focus measures proposed in spectral domains. An optimal focus measure is obtained by selecting an appropriate frequency-dependent window width. The performance of the proposed focus measure is compared with those of existing focus measures in terms of three-dimensional shape recovery. Experimental results demonstrate the effectiveness of the proposed focus measure.

© 2010 Optical Society of America

OCIS Codes
(100.3020) Image processing : Image reconstruction-restoration
(100.6890) Image processing : Three-dimensional image processing
(100.4994) Image processing : Pattern recognition, image transforms

ToC Category:
Image Processing

Original Manuscript: December 4, 2009
Manuscript Accepted: February 26, 2010
Published: April 15, 2010

Muhammad Tariq Mahmood and Tae-Sun Choi, "Focus measure based on the energy of high-frequency components in the S transform," Opt. Lett. 35, 1272-1274 (2010)

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  1. A. N. Simonov and M. C. Rombach, Opt. Lett.  34, 2111 (2009). [CrossRef] [PubMed]
  2. M. B. Ahmad and T. S. Choi, IEEE Trans. Circuits Syst. Video Technol.  15, 566 (2005). [CrossRef]
  3. A. S. Malik and T. S. Choi, Pattern Recogn.  40, 154 (2007). [CrossRef]
  4. S. K. Nayar and Y. Nakagawa, IEEE Trans. Pattern Anal. Mach. Intell.  16, 824 (1994). [CrossRef]
  5. M. T. Mahmood, S. O. Shim, and T. S. Choi, Opt. Eng.  48, 057203 (2009). [CrossRef]
  6. L. Sang-Yong, Y. Kumar, C. Ji-Man, L. Sang-Won, and K. Soo-Won, IEEE Trans. Circuits Syst. Video Technol.  18, 1237 (2008). [CrossRef]
  7. R. G. Stockwell, L. Mansinha, and R. P. Lowe, IEEE Trans. Signal Process.  44, 998 (1996). [CrossRef]
  8. R. A. Brown, M. L. Lauzon, and R. Frayne, IEEE Trans. Signal Process.  58, 281 (2010). [CrossRef]
  9. E. Sejdic, I. Djurovic, and J. Jiang, EURASIP J. Adv. Signal Process.  672941, 13 (2008).

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