为低成本远程获取植被冠层半球图像信息,从而得到叶面积指数这一重要的生态学参数,提出了一种远程叶面积指数半球图像采集系统.该系统采用嵌入式平台、低成本图像传感器与鱼眼镜头组成的现场节点获取植被冠层半球图像.冠层半球图像采集时节点还对环境日光辐照及温湿度进行实时监测,以便剔除无效数据及进行节点维护.上位机与现场节点间利用3G网络进行交互.上位机对获取的冠层图像使用像素校准与超分辨率技术提高图像质量,从而抑制由于鱼眼成像畸变与图像辨析度不足而在叶面积指数计算中引入的误差.测试结果表明,该系统可有效地对植被冠层图像进行低成本远距离采集,并得到误差较小的叶面积指数计算结果.
To get the hemispherical photography of plant canopy for leaf area index, a remotehemispherical image acquisition system is presented. Based on embedded platform, low cost image sensor and fish eye lens In-lied node is presented to achieve hemispherical image of plant canopy at distance with low cost. Solar radiation and temperature/humidity data are obtained for invalid hemispherical image elimination and node maintenance too. Host computer interacts with in-field node by 3G network. The hemispherical image calibration and super resolution are used to improve canopy image quality in host computer. Test results show that the remote canopy image collection system can collect remote canopy image with lower cost and get leaf area index evaluation results with lower error.