目的:特征检测是工业CT体数据处理中的重要问题,线特征是其重要特征之一,其检测效果将直接影响模式识别和分类。方法:有限线积分变换(finite line integral transform,简称FLIT)作为近年来新出现的一种多尺度几何分析方法,尤其适合于描述2D图像的线性奇异性。文中在2D-FLIT的理论基础上,将其推广到3D的情形,并结合图像融合和数学形态学的方法提出了两种基于FLIT的提取工业CT体数据中线特征的方法:一种是直接对工业CT体数据整体进行线特征的提取(3D-FLIT提取方法);一种是先对工业CT体数据按某个方向进行切片划分,再对每张切片进行线特征的提取(2D-FLIT提取方法)。结果:实验表明,与小波的方法相比,上述两种方法能有效地提取体数据中的线特征。结论:该文的方法能对工业CT体数据中的线特征进行有效提取,为后续相关的数据处理(如逆向工程)打下坚实的基础。
Abstract
Objective: Linear feature extraction is very important in image processing. In ICT cubic data
line is one of the important features. The lines’ extraction efficiency will directly affect the performance of pattern recognition and classification. Method: Finite line integral transform (FLIT) is a new method based on the concepts of multiscale geometric analysis (MGA). Using a series of fixed templates in different scales
FLIT gets a series of decomposition images containing the original image’s information at different scales and directions. FLIT is invertible and non-wrap
which is very successful in image denoising
line extraction and recognition when applied to images with line singularities. Based on the concept of 2D-FLIT
this paper generalize it to the case of 3D
attaining the formulas of 3D-FLIT and inverse 3D-FLIT. In this paper
in order to extract linear feature of ICT cubic data
the authors present two methods based on FLIT (2D-FLIT or 3D-FLIT)
including other image processing
such as image fusion and morphological. The first strategy is the idea of 3D-FLIT applying on the ICT cubic data directly for detecting linear features. The second strategy is the idea of 2D-FLIT applying on each slice in some direction of the ICT cubic data for detecting linear features. Then different directions’ images are fused for obtaining the linear features. Finally morphology image processing is used for extracting useful components of the linear features. Result: Numerical experiment results prove the efficiency of the proposed methods compared with wavelet method. Conclusion: Comparatively speaking
because the first strategy avoids slice dividing and saves the voxel relation between adjacent slices
its extracting linear features’ result is better and full than the second strategy. But
the second strategy is simpler and has less computation time. So
each of the two strategies has its own strong point.