2015 Unmanned aerial system (UAS)-derived orthoimage mosaics and digital terrain models of the SE lava flow margin, Holuhraun lava flow-field, Vatnajökull National Park, Iceland

Using a Phantom 3 Pro imaging system, aerial images were acquired over a short section of the SE Holuhraun lava flow margin, adjacent interior and adjacent river systems. Images were initially geocoded using the device's onboard GPS and a ground control points (GCPs) network. Final products were coregistered to more precise geocoded image data collected later in 2016. Images were processed into geodetically-controlled digital terrain models (DTMs) and orthomosaics using the commercial software package Pix4Dmapper Pro version 2.0.81. In Pix4Dmapper Pro, data products were geocoded by attributing the 3D coordinates of geocoded image coregistration targets to corresponding pixels in a subset of 2D images. The 2016 image data used for coregistration utilized DGPS measurements. To estimate the localization accuracy, we used a network of N = 7 coregistration points; the resulting mean of the root mean square error (RMSE) of x, y, and z directions (i.e., latitude, longitude, and elevation) is 10.6 cm. Both the DTM and orthomosaic products have a spatial resolution of 2 cm/pixel, but the DTM has an effective resolution of ~4 cm/pixel.Topic Categories (ISO 19115)elevation, geoscientificinformation, imageryBaseMapsEarthCoverFeature and Attribute DefinitionsA georeferenced raster displaying elevation data generated from digital camera image data using multi-view stereophotogrammetry methods.Date of Content2015-08-24For inquiries regarding the contents of this dataset, please contact the Corresponding Author listed in the README.txt file. Administrative inquiries (e.g., removal requests, trouble downloading, etc.) can be directed to [e-mail] item is part of Unmanned aerial system (UAS)-derived orthoimage mosaics and digital terrain models of the northeastern portion of the Holuhraun lava flow-field, Iceland

本数据集采用精灵3专业版（Phantom 3 Pro）成像系统，于冰岛赫鲁赫拉熔岩流东南部的小段边缘、邻近内部区域及毗邻河道系统上空获取航空影像。影像最初通过设备机载GPS与地面控制点（Ground Control Points, GCPs）网络完成地理编码。最终产品与2016年后期采集的更精确地理编码影像数据进行配准。本研究使用商用软件Pix4Dmapper Pro 2.0.81版本，将影像处理为受大地测量控制的数字地形模型（Digital Terrain Models, DTMs）与正射影像镶嵌图。在Pix4Dmapper Pro中，通过将影像配准目标的三维坐标赋予部分二维影像的对应像素，完成了数据产品的地理编码。本次配准所使用的2016年影像数据采用了差分全球定位系统（Differential GPS, DGPS）测量数据。为评估定位精度，研究团队使用了包含7个配准点的网络，最终得到x、y、z方向（即纬度、经度与高程）的均方根误差（Root Mean Square Error, RMSE）平均值为10.6厘米。数字地形模型与正射影像镶嵌图的空间分辨率均为2厘米/像素，但数字地形模型的有效分辨率约为4厘米/像素。主题分类（符合ISO 19115标准）：高程、地球科学信息、影像、影像底图与地表覆盖；要素与属性定义：一种通过多视图立体摄影测量（multi-view stereophotogrammetry）方法，由数码相机影像数据生成的包含高程数据的地理参考栅格（georeferenced raster）。内容发布日期：2015-08-24。若对本数据集内容有疑问，请联系README.txt文件中列出的通讯作者。行政类咨询（例如移除申请、下载故障等）可发送至[e-mail]。本数据集隶属于“冰岛赫鲁赫拉熔岩流东北部无人机系统（Unmanned Aerial System, UAS）获取的正射影像镶嵌图与数字地形模型”数据集系列。