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Wiener Filter for Image Restoration

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Wiener Filter for Image Restoration Wiener Filter for Image Restoration The Wiener filter is a powerful technique used for image restoration, specifically designed to handle both image degradation and noise. Unlike simple inverse filtering, the Wiener filter incorporates statistical characteristics of noise and degradation into its restoration process. Objective The primary objective of the Wiener filter is to estimate the original, uncorrupted image f from a degraded image g while minimizing the mean square error between the estimated image and the original. The error measure is defined as: where E{•} denotes the expected value, and \hat{f} is the estimate of the original image. Mathematical Formulation The Wiener filter considers both the degradation function and the noise in the image restoration process. The filter aims to find the optimal estimate of the original image by minimizing the mean square error, under the following assumptions...

Mean Filters: In-Depth Explanation

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Mean Filters: In-Depth Explanation Mean filters are essential tools in digital image processing, primarily used for noise reduction and image smoothing. They work by replacing each pixel in an image with the mean (or average) value of the pixels within a specified neighborhood around that pixel. The basic idea is to reduce noise by averaging out pixel intensity variations, which helps in smoothing the image. However, different types of mean filters offer varying benefits and drawbacks depending on the nature of the noise and the desired level of smoothing. 1. Arithmetic Mean Filter The Arithmetic Mean Filter is the most straightforward type of mean filter. It calculates the average of the pixel values in a neighborhood (typically a square or rectangular window) centered around each pixel in the image. The size of the window is usually odd (e.g., 3x3, 5x5) to ensure that there is a central pixel. Mathematical Representation Given a corrupted image g(x, y) , the arithmetic mean...