A Preprocessing Approach For Image Analysis Using Gamma Correction
نویسندگان
چکیده
This paper presents a new, simple and robust image enhancement algorithm for image analysis by modifying the gamma value of its individual pixels. Considering the fact that gamma variation for a single image is actually nonlinear, the proposed method locally estimates the gamma values in an image. First, for local gamma correction the image is divided to overlapping windows and then the gamma value of each window is estimated by minimizing the homogeneity of cooccurrence matrix. This feature represents image details, the minimum value of this feature shows maximum details of the image. As the enhanced image shows details better, the method is a useful preprocessing technique for image analysis. In this study, it is shown that the proposed method has performed well in improving the quality of images. Subjective and objective image quality assessments used in this study attest superiority of the proposed method compared to the existing methods in image quality enhancement.
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