A Robust Edge Detection Approach in the Presence of High Impulse Noise Intensity through Switching Adaptive Median and Fixed Weighted Mean Filtering

IEEE Trans Image Process. 2018 Jul 18. doi: 10.1109/TIP.2018.2857448. Online ahead of print.

Abstract

This study introduces a robust edge detection method that relies on an integrated process for denoising images in the presence of high impulse noise. This process is shown to be resilient to impulse (or salt and pepper) noise even under high intensity levels. The proposed switching adaptive median and fixed weighted mean filter (SAMFWMF) is shown to yield optimal edge detection and edge detail preservation, an outcome we validate through high correlation, structural similarity index and peak signal to noise ratio measures. For comparative purposes, a comprehensive analysis of other denoising filters is provided based on these various validation metrics. The nonmaximum suppression method and new edge following maximum-sequence are two techniques used to track the edges and overcome edge discontinuities and noisy pixels, especially in the presence of high-intensity noise levels. After applying predefined thresholds to the grayscale image and thus obtaining a binary image, several morphological operations are used to remove the unwanted edges and noisy pixels, perform edge thinning to ultimately provide the desired edge connectivity which results in an optimal edge detection method. The obtained results are compared to other existing state-of-the-art denoising filters and other edge detection methods in support of our assertion that the proposed method is resilient to impulse noise even under high-intensity levels.