智能手机单片摄影测树技术研究与试验

Research and Experiment on Monolithic Photogrammetry for Smartphone

森林因子采集是林业观测的重中之重,智能手机为林业调查提供了新思路、新手段。为了更高效、精确的观测森林,以智能手机为载体,摄影测量学、测树学原理为理论基础,Java为开发语言,设计了一套单片摄影测树系统。系统仅利用智能手机的定焦镜头正直拍摄一张图像,即可进行单木的胸径、树高、材积的自动解算,同时,还可进行林分平均胸径、蓄积量和林分密度的自动解算。通过对200株立木进行胸径、树高、材积测量试验,对15块样地进行林分平均胸径、林分密度和林分蓄积量测量试验。结果表明,单木因子测量的相对偏差为4.95%~5.86%,相对均方根误差为6.09%~7.46%,林分因子测量的相对偏差为0.51%~1.46%,相对均方根误差为7.47%~8.6%。以上指标均高于传统林业测量的精度要求,该技术可以在林业调查中推广使用。

Forest factor acquisition is the most important part of forestry observation.And the smartphone has opened up a new world for forestry survey.Based on smartphone,photogrammetry and tree measurement principles,and taking Java as the development language,this paper designed a single photogrammetric tree measurement system in order to carry out forest observation more efficiently and accurately.This system could get the individual tree diameter at breast height(DBH),individual tree height,individual tree volume,stand average DBH,stand volume and stand density only using the fixed focus lens of the smartphone to shoot a photo.The estimates from the smartphone were compared to traditional forestry survey tools.The data consisted of 200 individual tree and 15 sample plots.The results showed that the Bias%of individual tree factor was 4.95%~5.86%,the relative root-mean-square error(RMSE)of individual tree factor was 6.09%~7.46%.The Bias%of stand factor was 0.51%~1.46%and the RMSE%of stand factor was 7.47%~8.6%.The above indexes were higher than the precision requirements of traditional forestry survey,and this technology could be popularized and used in forestry survey.