Despeckling of ultrasound images of bone fracture using RADWT based non-linear filtering

Abstract

Despeckling in ultrasound medical images is of great interest. Due to presence of speckle, experts may not be able to extract correct and useful information from the images. This chapter presents a method for despeckling based on a new rational-dilation wavelet transform (RADWT) and non-linear bilateral filter (BLF). The RADWT, a new family of the discrete wavelet transform for which frequency resolution can be varied, provides effective representation of the noisy coefficients. Bilateral filter and thresholding scheme are applied to the noisy RADWT coefficients to improve the denoising efficiency and preserve the edge features effectively. The proposed method also helps to improve the visual quality of bone fracture ultrasound images. The performance of the proposed method is evaluated on the different ultrasound images of bone fracture and results show significant improvement not only in the speckle reduction but also in the edge preservation performance. © 2014 Springer Science+Business Media Dordrecht.