Characterization and identification of woods by the Fourier transform image analysis

在木结构傅里叶变换的应用中，对点映射法、极坐标功率谱分析等FFT前、后处理方法进行了改进，在实用层面上实现了傅里叶变换图像分析系统。该系统在木材识别和木材质量两个领域都取得了很好的效果。主要研究结果如下：(1)提供了50种日本主要木材的管胞和木材纤维的分布，并收集了它们的功率谱模式。他们根据角度和频率分布函数进行了数学评估，更不用说对功率谱模式的视觉判断了。管胞和纤维排列出其独特的分布，与每种木材有关。通过极坐标分析得到的数字特征将用于木材识别和木材质量。(2)对33种阔叶树的导管分布进行分析，得到了许多非常敏感的特征，这些特征可以与每个树种相关联。此外，血管和纤维的负分布带来了更多关于射线和轴向薄壁组织的意外信息。此外，结合傅立叶变换图像分析系统，特别是相关函数，对木材结构的三维分析提出了挑战。

In the application of the Fourier transfrom on wood structures, some Pre-FFT and Post-FFT procedures such as the dot mapping method and also the polar coordinate analysis of power spectral patterns were improved, so the Fourier transform image analyzing system was accomplished in the practical level. This new system was proved to be very effective on the both fields of wood identification and wood quality. Result obtained are as follows.(1)Distribution of tracheids and wood fibers of fifty species of major Japanese woods were offered to the analysis, and collected thier power spectral patterns. They were evaluated mathematically on the angular and frequency distribution functions, not to say nothing of visual judgment of power spectral patterns. Tracheids and fibers were shown to arrange thier peculiar distribution, being related to each wood species. Numerical characters obtained by the polar coordinate analysis will be used on the wood identification and wood quality.(2)When vessel distribution of 33 hardwoods were analyzed, many and very impressible characters were obtained and could be related to each species. And more, unexpectable informations on ray and axial parenchyma were brought by the negative distribution of vessels and fibers.In addition to the above result, three-dimensional analysis on wood structure was challenged in combined with the Fourier tranform image analyzing system, especially with the correlation function.