Myung-yoon LEE, Hern-soo HAHN, Young-joon HAN
(Dept. of Electronic Engineering，Soongsil University，Seoul 156-743, Korea)
Abstract-A conventional global contrast enhancement is difficult to apply in various images because image quality and contrast enhancement are dependent on image characteristics largely. And a local contrast enhancement one not only causes a washed-out effect, but also has a blocking effect. To solve these drawbacks, this paper derives an optimal global equalization function using variable size block based local contrast enhancement. The optimal equalization function makes it possible to get a good quality image through the global contrast enhancement. The variable size block segmentation is firstly executed using intensity differences as a measure of similarity. In the second step, the optimal global equalization function is obtained from the enhanced contrast image having variable size blocks. Conformed experiments show that the proposed algorithm produces a visually comfortable result image.
Key words-global contrast enhancement; local contrast enhancement; optimal equalization function, block segmentation, variable size block
Manuscript Number: 1674-8042(2011)supp1.-0065-04
doi: 10.3969/j.issn.1674-8042.2011.supp1.014
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