Self-adapting method for filtering image with edge being retained

Abstract

The invention relates to an edge-preserving adaptive image filtering method. The technical feature is that: firstly, the extremum method is used to detect the pixels polluted by the salt and pepper noise in the noise image, and then the gray value of the noise pixel is corrected by using the adaptive filtering method to obtain Remove the image of salt and pepper noise; then carry out stationary wavelet decomposition on the image to obtain the corresponding low-frequency components and high-frequency components; keep the low-frequency components unchanged, use the coefficient correlation method to mark the pixels of the high-frequency components as noise or edge, if If a pixel is marked as an edge, keep its value unchanged; otherwise, the adaptive neighborhood method is used to shrink the wavelet coefficients; finally, the processed wavelet coefficients are subjected to stationary wavelet inverse transform to obtain a denoising image. The Gaussian noise filtering method of the invention can effectively remove the mixed noise and at the same time better maintain the detailed information of the image, and its performance is better than some traditional image filtering methods.

Description

technical field [0001] The invention relates to an edge-preserving adaptive image filtering method, which belongs to the technical field of image processing, and in particular to a mixed noise image filtering method. Background technique [0002] During the acquisition and transmission of digital images, sensors or transmission channels often generate noise. The existence of noise greatly reduces the quality of the image, making later processing such as image segmentation, feature extraction and target recognition difficult, so filtering the noisy image becomes a very important task. Among various forms of noise, salt-and-pepper noise and Gaussian noise are the two most common, and thus have attracted more attention. [0003] For the removal of salt and pepper noise, the more common method is the nonlinear median filter. Since the median filtering method uses the same window for processing all pixels, the denoising result cannot maintain details such as edges. At present,...

AI Technical Summary

Problems solved by technology

Although this method uses different thresholds for high-frequency components of different scales, it unconditionally shrinks all pixels at a certain scale, and uses a unified threshold, so the details of the image will also be lost to a certain extent. information

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