Non-local adaptive hysteresis despeckling approach for medical ultrasound images

Abstract

Speckle noise is a major problem in medical ultrasound imaging that reduces the image quality and leads to a negative impact on further diagnosis. In this paper, aiming to alleviate the effect of speckle, a new ultrasound image noise reduction approach called Non-local Adaptive Hysteresis Despeckling is proposed, which effectively exploits data redundancy not only for suppression of speckle noise but also for preserving meaningful structural details in ultrasound images. Since Hysteresis smoothing-based filters are initially introduced to eliminate additive white Gaussian noise, we attempt to adapt this category of filters to the signal-dependent and multiplicative nature of speckle noise in ultrasound images. Furthermore, the local functionality of Hysteresis smoothing-based filters, which is a limitation of their effectiveness, is addressed by proposing more efficient non-local weighting and averaging schemes to be more compatible with the speckle noise model. The qualitative and quantitative evaluations of the simulated and real clinical ultrasound images show that the proposed method can outperform other state-of-the-art methods.