关键词: 超声图像去噪, 斑点指数C, 中值滤波算法

Abstract: The inherent speckle noise in ultrasound images severely degrades the image interpretation and affects the diagnostic results because of the characteristics of coherence in ultrasonic imaging.The speckle noise also increases the difficult for the following：up image processing tasks，such as edge detection，feature extraction and so on.Thus，it’s very important that reserves the edge characters effectively based on speckle noise removing.This paper divides the ultrasound image into uniform，speckle including and edge regions by studying the characters of speckle index C in neighborhood，then handles these regions differently.The simulation results prove that this methord is simple and valid，it removes the speckle noise and reserves the edge characters at the same time.The peformance of the method is better than the traditional median filtering algorithm.

Key words: ultrasound image denoising, speckle index C, median filtering algorithm