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^1/_{16} & ^1/_{2}& ^1/_{16}\\\\  ^1/_{16} & ^1/_{16} & ^1/_{16} \end{array} \right)  \]  \eq_1  Convolving the image with this kind of kernel reduces the noise while retaining more of the original signal than simple averaging. Contributions from the i-th layer around the center will have the same weight as the central pixel. In this work we use the kernel with \(n=1\).