Multiresolution Based Hybrid Filtering Technique for Despeckling Ultrasound Images

Abstract

Ultrasound imaging is the most commonly used imaging system for disease diagnosis. Speckle noise is an inherent property of medical ultrasound imaging. Since speckle may hinder the detection of image details it is typically regarded as noise and there is a strong need to remove speckle effectively for good and fast interpretation. Multiresolution analysis is the important tool in eliminating noise from images effectively. In this paper an algorithm is proposed that uses multiresolution analysis through which it is possible to distinguish noise and image information better than at one resolution level. The proposed algorithm combines the features of filtering techniques in multiresolution framework to combine the benefits that each one can contribute. This algorithm maintains a balance between speckle suppression and feature preservation. The result is shown to be promising and outperforms other despeckling approaches. Performance evaluations are performed by using statistical parameters like Mean Square Error (MSE), Signal to Noise Ratio (SNR), Peak Signal to Noise Ratio (PSNR), Speckle Index (SI) and Edge Preservation Index (EPI).