A Review of Image Denoisng Techniques

One of the most fundamental challenges in the field of image processing is image denoising, where the primary objective is to estimate the original image by removing noise from a noisy version of the image. Many algorithms have been proposed so far for removal of noise from the digital images. This paper review different image denoising techniques. It has been found that the most of the previous denoising techniques like gaussian filtering; bilateral filtering may remove fine details from the image. So a non local method known as non-local means solve this problem. This technique estimates a noise-free pixel as a weighted average of all similar pixels in the image. Non local euclidean median is a image denoising technique. Denoising performance of a noisy image improved by replacing the mean by the euclidean median and this new denoising algorithm the non-local euclidean medians (NLEM). This technique proves that the median is more vigorous to outliers than the mean