SGS-SRAD Filter for Denoising and Edge Preservation of Ultrasound Images

The speckle noise being multiplicative in nature degrades the quality of ultrasound images. This noise limits the contrast resolution, complicates quantitative and visual measurements and diagnosis based on image. In this work, a hybrid denoising technique is suggested which comprehends the properties of two speckle noise suppression filters. The proposed work combines noise reduction attribute of Savitzky-Golay smoothing (SGS) filter and edge preserving characteristic of speckle reducing anisotropic diffusion (SRAD) filter to denoise ultrasound images. The proposed hybrid filter is applied and tested on synthetic images, B-scan simulated images, and real ultrasound images. The conventional filters i.e. median, Lee, Wiener, Kuan, Frost, Non-local means, squeeze box filter, SGS and SRAD are also designed for comparative analysis. The quantitative and qualitative results of denoised synthetic and real ultrasound images show that the proposed SGS-SRAD filter outperforms the conventional denoising methods.