An Approach on Suppressing Speckle in Ultrasound Images

Due to the logarithmic compression of the echo envelope by clinical ultrasound systems, Nakagami distribution can be more general to described the statistics of speckle and be used to design an unsharp mask filter to adaptively reduce speckle. This paper provides a novel adaptive speckle suppressing anisotropic diffusion(ASS-ANDl) method for medical B-scan ultrasonic images. The unsharp mask filter is evolved and combined with anisotropic diffusion method by introducing coefficient of variation based on local statistics of speckle. Performance of the new method has been tested on the ultrasonic images experimentally, we demonstrate that ASS-AND1 approach outperforms the conventional anisotropic diffusion(ANDl) in reducing speckle and preserving useful details.