X射线数字图像中光场矫正问题的一种实用算法  

Practical Algorithm for the Problem of Light Field Correction in X-Ray Digital Image

作　　者：林刚[1] 张锋[1] 张登福[1] 蒋大宗[1] 

机构地区：[1]西安交通大学生命科学与技术学院,西安710049

出　　处：《西安交通大学学报》2002年第8期830-833,共4页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目 (396 310 2 0 )

摘　　要：由于X射线数字图像光场分布呈抛物面状 ,据此提出了一种基于最小二乘法的实用算法 ,用以解决X射线数字图像光场矫正问题 .该算法首先取空白图像中最亮区的平均灰度作为参考值 ,并将空白图像中所有像素点的灰度值与相应的系数相乘后规则化至该参考值 ,然后采用抛物面函数对系数图像进行最小二乘法拟合生成矫正算子 ,最后利用该矫正算子对目标图像进行矫正 .实验表明 ,该方法所生成的矫正算子不仅稳定、可靠 。Experiment shows that the light field of the X ray digital image is in paraboloidal distribution.A practical algorithm based on the least mean square (LMS) algorithm for the correction of X ray digital image is proposed.Firstly, the average gray level of the highlight region in the empty image is used as a referential value, and all the pixels in the empty image are multiplied by the corresponding coefficient to get the referential value.Then, a paraboloidal function is adapted to fit the coefficient image and to make the correction operator.Eventually, the correction operator is applied to correct the objective image. It is shown that the operator generated by this algorithm is stable and reliable, and it can correct the non uniform illumination in the objective image without increasing the noise.

关 键 词：X射线数字图像 光场矫正 光场分布 成像原理 医学图像 图像处理 

分 类 号：R814.43[医药卫生—影像医学与核医学] TN911.73[医药卫生—放射医学]