Extraction of individual tree branch parameters from skeleton model based on point cloud data.

Terrestrial laser scanning technology plays an important role in extracting individual tree parameters. Meanwhile, graphics algorithms provides feasible methods for evaluating structural parameters. In this paper, a method of extracting individual tree structural parameters has been put forward. We extracted individual trees skeleton model by SkelTre algorithm. Then branch structure was identified by topological feature of the skeleton model from searching the connection nodes among different branches. We calculated branch length and made the cross-section through the skeleton model at branch connection points. Moreover, convex hull algorithm was used for extracting a plane polygon and calculating branch diameter through the point cloud outsourcing. From the regression analysis between field measurement and model estimated measurement, we acquired the compared branch length and diameters. Branch lengths regression of filed measurement and model estimation performed with Y=1.006X+1.335, significant value of 0.001. Meanwhile, branch diameters regression of filed measurement and model estimation performed with Y=0.923X+0.105, significant value of 0.000. The experiment results demonstrate that extracting skeleton model to identify individual trees branch structure and acquire structure parameters, such as branch length and branch diameter is applicable and promising.