Dr. Rajesh R., Associate Professor and Head, Department of Computer Science, Central University of Kerala, India

Speech Title: Do we need pre-filtering in NLM? – A study on ultrasound images

Abstract: The presence of speckle noise in ultrasound images creates difficulty in effectual medical inference. The effect of pre-filtering in ultrasound images using Non-local means (NLM) algorithm is studied. Before using the NLM algorithm, prefiltering is done using filters like, median, Lee, anisotropic diffusion (AD) and Laplace of Gaussian (LoG). An ultrssound image with added speckle noise (with σ=0.2) is taken and denosed using NLM with and without prefilter. It can be seen from Tab. 1 that prefiltering before applying NLM has a great impact during denoising.



Prefiltering before applying NLM better helps in donosing an image.