Illumination based Sub Image Histogram Equalization: A Novel Method of Image Contrast Enhancement
نویسندگان
چکیده
A novel Illumination based Sub-Image Histogram Equalization (ISIHE) method for contrast enhancement for low illumination gray scale images is presented in this paper. As the main crux of paper, illumination thresholds are computed and used to divide the original image into sub-images of different intensity levels. To control the enhancement rate, the histogram is clipped using a threshold value that represents the average number of grey level occurrences in the image. Each individual sub histogram is equalized independently and all sub images are integrated into one complete image for analysis as a final step. The experimental results are compared with other Histogram Equalization (HE) methods and ISIHE has shown promising results.
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