Speckle suppression by adaptive nonlinear filtering

S. Ghofrani1,2, A. Ayatollahi1
1Electrical Engineering Department, Iran University of Science and Technology, Iran
2Islamic Azad University, Iran

Tóm tắt

Using a good statistical model of speckle formation is important in designing an adaptive filter for speckle reduction in ultrasound B-scan images. Most clinical ultrasound imaging systems use a nonlinear logarithmic function to reduce the dynamic range of the input echo signal and emphasize objects with weak backscatter. The statistic of log-compressed images for Nakagami distribution was derived (Ghofrani et al. 2001) and in this paper we use the results for designing an adaptive nonlinear filter in speckle reduction. We processed two original ultrasound images of kidney and liver to demonstrate the efficiency of the designed filter.

Từ khóa

#Speckle #Adaptive filters #Ultrasonic imaging #Filtering #Dynamic range #Backscatter #Statistical distributions #Nakagami distribution #Nonlinear filters #Liver

Tài liệu tham khảo

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