Abstract: Image improvement is a processing on an image to make it more appropriate for certain applications. The Image denoising is the manipulation of the image data to produce a visually high quality image. The aim of image enhancement is to improve the visual appearance of an image or to provide a better transform representation for future image processes. At present there are a variety of methods to remove noise from digital images. Filter techniques are mainly used for de-noising, smoothness and sharpening of images. In this paper we are designed a new modified decision based unsymmetric and Symmetric trimmed median filter for removal of these different noises by using median filter, Adaptive median filter, and Decision based Adaptive median filter. Most of the previously known techniques are applicable for the denoising of images corrupted with less noise density. Here a new decision based technique has been presented which shows better performances than those already being used and the new proposed algorithm will definitely protect the image from noise and distortion. In this paper we are presented different denoise filtering techniques for image quality improvement and this concept is applied to the different images and compares their performance parameters such as MSE, PSNR, correlation etc.

Keywords: impulse noise, non linear filters, MSE, PSNR, correlation.