林业工程学报2017，Vol.2Issue(5)：109-114,6.DOI:10.13360/j.issn.2096-1359.2017.05.019
一种对年轮图像双边滤波增强的树龄测量方法
Improving the tree-age measurement by enhancing the tree-ring image with bilateral filter
摘要
Abstract
Tree-ring image analysis has been proven to be a promising tool for predicting tree age and has attracted more and more attention. Many approaches were proposed to detect and count tree-ring boundaries in images of wood cross section. However, factors such as stain, saw mark and pore often lower the accuracy of tree-age prediction. In this paper, a practical method was proposed for tree-ring image enhancement and tree-age measurement. The images of wood cross sections were first enhanced by the bilateral filtering method due to its excellent noise reduction per-formance. The gray variation caused by stain, saw mark and pore was reduced, whereas the information of tree-ring edges was not affected. Then, an improved Canny algorithm was used to detect the edges of tree rings. During this process, gradients in directions of the horizon, the vertical, 45° and 135° were computed to overcome the drawback of the conventional Canny algorithm. Finally, a majority rule was proposed so that the tree-ring boundaries could be counted with high accuracy even though broken edges existed in the images. The tree-age measurement was thus a-chieved. In this study, four wood cross section images were used as the samples. One of them was polished and the other three remained untreated after saw cutting. The experimental results show that the proposed method can achieve good performance. Smooth and clear edges can be obtained even though stains, saw marks and pores exist. The tree a-ges obtained were consistent with the real data. The result of this study indicates that the proposed method has exten-sive application potentiality in extracting tree-age information from wood cross section images.关键词
年轮图像/图像增强/树龄测量/双边滤波/多数投票Key words
tree-ring image/image enhancement/tree-age measurement/bilateral filtering/majority voting分类
农业科技引用本文复制引用
王燕凤,冯海林,杜晓晨,方益明..一种对年轮图像双边滤波增强的树龄测量方法[J].林业工程学报,2017,2(5):109-114,6.基金项目
国家自然科学基金(61302185,61272313) （61302185,61272313）
浙江省自然科学基金( LQ14F020014, LY15F 020034) （ LQ14F020014, LY15F 020034）
浙江省科技厅科技计划项目(2015F50025) （2015F50025）
浙江省新苗人才计划项目(2015R412048). （2015R412048）
