Method and apparatus for adjusting the contrast of an image

Image analysis – Histogram processing – With a gray-level transformation

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C382S274000

Reexamination Certificate

active

07738698

ABSTRACT:
A method and apparatus for adjusting the contrast of an image, in which each pixel in the image has an initial brightness level that is within a range of brightness levels between a minimum brightness level and a maximum brightness level. For each brightness level within the range, the number of pixels that have the same initial brightness level is counted. The pixels are divided into at least two types by identifying the or each set of pixels having initial brightness levels in which each of a plurality of adjacent ones of said brightness levels has more pixels than a threshold number. The pixels of the plurality of adjacent ones of said brightness levels are treated as a first type. The remaining pixels are treated as a second type. For the or each set of pixels of the first type, contrast enhancement is carried out separately on those pixels.

REFERENCES:
patent: 4731863 (1988-03-01), Sezan
patent: 6049626 (2000-04-01), Kim
patent: 6157748 (2000-12-01), Taleblou et al.
patent: 6236751 (2001-05-01), Farrell
patent: 7382414 (2008-06-01), Nakajima et al.
patent: 2003/0161549 (2003-08-01), Lei et al.
patent: 0 501 728 (1992-09-01), None
patent: 1 022 679 (2000-07-01), None
patent: 1 482 447 (2004-12-01), None
patent: 1 605 406 (2005-12-01), None
Gonzalez and Woods. “Digital Image Processing.” Addison-Wesley Publishing Company, 1992, pp. 173-180.
J. Alex Stark, Adaptive Image Contrast Enhancement Using Generalizations of Histogram Equalization, IEEE Transactions on Image Processing, vol. 9, No. 5, May 2000 (pp. 889-896).
R.C. Gonzales and Richard E. Woods, Digital Imaging Processing; Prentice Hall, New Jersey (2001), Chapter 3 Image Enhancement in the Spatial Domain, Section 3.3 Histogram Processing (pp. 88-95).
Stephen M. Pizer, et al., Adaptive Histogram Equalization and Its Variations; Computer Vision, Graphics, and Image Processing 39, 1987 (pp. 355-368).
European Search Report for Application No. EP 06 25 1101, dated Nov. 20, 2006, (4 pages).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method and apparatus for adjusting the contrast of an image does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and apparatus for adjusting the contrast of an image, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for adjusting the contrast of an image will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-4206764

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.