Generalization of Impulse Noise Removal

In this paper, a generalization for the identification and removal of an impulse noise is proposed. To remove the salt-and-pepper noise an Improved Directional Weighted Median Filter (IDWMF) is proposed. Number of optimal direction are proposed to increase from four to eight directions to preserve the edges and to identify the noise, effectively. Modified Switching Median Filter (MSMF) is proposed to replace the identified noisy pixel. In which, two special cases are considered to replace the identified noisy pixel. To remove the random-valued impulse noise, we have proposed an efficient random-valued impulse noise identifier and removal algorithm named as Local Noise Identifier and Multi-texton Removal (LNI-MTR). We have proposed to use the local statistics of four neighbouring and the central pixel for the identification of noisy pixel in current sliding window. The pixel identified as noisy, is proposed to replace by using the information of multi-texton in current sliding window. Experimental results show that the proposed methods cannot only identify the impulse noise efficiently, but also can preserve the detailed information of an image.