基于医学CT断层图像中物质灰度呈正态分布的特性,提出一种新的插值算法。先分割CT断层图像,再为每个插值点搜索属于同种物质的最佳匹配点对,最后基于物质灰度呈正态分布特性获取插值权值,计算出插值点的灰度值。针对灰度值相差较大的匹配点对,传统的线性插值方法容易生成误差,新算法避免了这些插值点误差的产生。对于存在较多灰度值差异大的匹配点对的4组测试切片,测试结果表明,与匹配点对间传统的线性插值方法相比较,新算法的标记点均偏差平均降低29.55%,说明新算法具有良好的插值效果。
A new interpolation algorithm based on intensity normal distribution of matters in medical CT slices was presented in this paper.First,the CT slices were classified into different matters,next,the best matching pairs belonging to the same matter was searched for every interpolated pixel.After that the weighs based on intensity normal distribution were used to calculate the gray level for the interpolated pixels.The traditional linear interpolation could introduce artifacts between the best matching pairs whose gray level differed significantly.The new algorithm could avoid those artifacts in these cases.For the four groups of experimental slices which had a lot of the best matching pairs whose gray level differed significantly,experimental results showed that the new algorithm decreased the average errors of the marked pixels 29.55% averagely more than the traditional linear interpolation between the best matching pairs.