Abstract:

Dividing height of living tree into clean length and height of canopy, obtaining the picture pair of clean height by close shot, the diameter and tilts angles in different positions of clean length are rebuilt by mean of stereo vision. Based on the method, the height of canopy is estimated and the height of tree is obtained, therefore, in the process of tree height reconstructing through stereo vision, the problem from canopy occlusion is solved. The experiment includes two kinds of trees: Ginkgo biloba and Metasequoia glyptostroboides. Comparing with actual tree height, max absolute error of reconstructing height is 0.043 5, min is 0.007 2, tree No. 3 is 0.002 6 in one aspect. These result show the method of tree height reconstructing in closed stand through stereo vision and stem curve is feasible.

Key words: occlusion, tree height measurement, stand investigation, stereo vision, 3D-reconstruction