This article [J. Electron. Imaging, 18, 023009 (2009)] was originally published online on 15 May 2009 with an error on page 11, in the first author biography.

The first author's name originally appeared here as “Chen-Chin Tsai.” It should read “Chung-Chih Tsai” as per the author affiliations on page 1.

Also, an acknowledgment was added on page 10 that states “This work is partly supported by the R.O.C. National Science Council through Grant NSC 97-2623-7-005-003-D.”

All online versions of the article were corrected on 11 June 2009. The article appears correctly in print.