BBFHE: Block-based Binomial Filtering Histogram Equalization
نویسندگان
چکیده
Histogram equalization is an efficient contrast enhancement algorithm. Global equalization is effective, but enhances only overall contrast, while local histogram equalization is more powerful, but computationally expensive. In this paper, a Block-based Binomial Filtered Histogram Equalization (BBFHE) algorithm is presented. The image is divided into blocks, and for each block a histogram is obtained by means of a binomial filter applied on the block histogram itself and on other neighboring block histograms. A binomial filter achieves better results than other low pass filters and can be computed very efficiently. Experimental results show that the proposed algorithm is several times faster – depending on the selected image size – with a comparable visual quality, than the previous fastest method. Key-Words: Local histogram equalization, binomial filtering, block based histogram equalization
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