锥束CT图像的自适应滤波预处理方法  

Slice Image Pretreatment for Cone-Beam Computed Tomography Based on Adaptive Filter

作　　者：黄魁东[1] 张定华[1] 金炎芳[1] 

机构地区：[1]西北工业大学现代设计与集成制造技术教育部重点实验室,陕西西安710072

出　　处：《核电子学与探测技术》2009年第5期1025-1029,共5页Nuclear Electronics & Detection Technology

基　　金：国家科技支撑计划重点项目(2006BAF04B02);教育部博士点基金新教师项目(20070699049)

摘　　要：根据锥束CT系统噪声的性质与序列切片图像的特点,提出一种锥束CT图像的自适应滤波预处理方法。首先建立噪声判断准则,将当前滤波像素的噪声分为两类:对于高斯噪声,采用自适应中心加权的改进均值滤波算法处理,并提出用高斯噪声的层间标准差估计取代层内偏移窗口标准差估计,提高了对序列图像进行滤波的准确性;对于脉冲噪声,采用自适应中值滤波算法处理。通过叶片蜡模的锥束CT切片图像预处理实验,表明该方法在去除噪声和保护细节两方面均表现良好。According to the noise properties and the serial slice image characteristics in Cone-Beam Computed Tomography （CBCT） system, a slice image pretreatment for CBCT based on adaptive filter was proposed. The judging criterion for the noise is established firstly. All pixels are classified into two classes： adaptive center weighted modified trimmed mean （ACWMTM） filter is used for the pixels corrupted by Gauss noise and adaptive median （AM） filter is used for the pixels corrupted by impulse noise. In ACWMTM filtering algorithm, the estimated Gauss noise standard deviation in the current slice image with offset window is replaced by the estimated standard deviation in the adjacent slice image to the current with the corresponding window, so the filtering accuracy of the serial images is improved. The pretreatment experiment on CBCT slice images of wax model of hollow turbine blade shows that the method makes a good performance both on eliminating noises and on protecting details.

关 键 词：自适应滤波 噪声判别 预处理 序列切片图像 锥束CT 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]