Image analysis – Histogram processing – With a gray-level transformation
Patent
1997-03-10
1999-10-05
Coles, Edward L.
Image analysis
Histogram processing
With a gray-level transformation
382171, 382271, 382273, 382274, 382282, 348254, 348672, 348673, 358455, 358522, 358532, G06K 938, G06T 540
Patent
active
059636653
ABSTRACT:
An image enhancing method using a mean-separate histogram equalization method is disclosed. An input image signal is divided into two sub-images in a picture unit according to a mean level of the input image signal. Then, cumulative density functions for each of the sub-images are calculated. Afterwards, the input sample is mapped into two gray levels, each of which belongs to a first range and a second range, by using first and second transform functions defined by use of the cumulative density functions, respectively. Finally, one of two mapped levels is selected depending on the magnitude of the input sample. As a result, the brightness of the given image can be preserved while the contrast is enhanced.
REFERENCES:
patent: 4682229 (1987-07-01), Coates et al.
patent: 4745465 (1988-05-01), Kwon
patent: 4912659 (1990-03-01), Liang
patent: 4952805 (1990-08-01), Tanaka
patent: 5214711 (1993-05-01), Neely et al.
patent: 5410618 (1995-04-01), Fowler
patent: 5426517 (1995-06-01), Schwartz
patent: 5450502 (1995-09-01), Eschbach et al.
patent: 5475507 (1995-12-01), Suzuki et al.
patent: 5598217 (1997-01-01), Yamaguchi
patent: 5614948 (1997-03-01), Hannah
patent: 5668737 (1997-09-01), Iler
patent: 5734746 (1998-03-01), Jaspers
patent: 5808697 (1998-09-01), Fujimura et al.
J.S. Lim, "Two-dimensional Signal and Image Processing," Prentice Hall, Englewood Cliffs, New Jersey, 1990.
R.C. Gonzalez and P. Wints, "Digital Image Processing," Addison-Wesley, Reading, Massachusetts, 1977.
J. Zimmerman, S. Pizer, E. Staab, E. Perry, W. McCartney and B. Brenton, "Evaluation of the Effectiveness of Adaptive Histogram Equalization for Contrast Enhancement," IEEE Tr. on Medical Imaging, pp. 304-312, Dec. 1988.
Y. Li, W. Wang and D.Y. Yu, "Application of Adaptive Histogram Equalization to X-ray Chest Image," Proc. of the SPIE, pp. 513-514, vol. 2321, 1994.
Russ, John C., "Image Processing Handbook", 1995, pp. 216-224.
Cho Yong-Hun
Kim Young-taek
Coles Edward L.
Rosenblum David
Samsung Electronics Co,. Ltd.
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