Inspire NI Digital Orthophotos Lower Saxony (DOP20)

Digital orthophotos (DOPs) are high-resolution, distortion-free images of the Earth’s surface. Since 2001, they have been produced by a computerised equalisation process with a geometric accuracy of approximately ± 0.4 m from aerial images, usually in scale 1: There are 12 000 perpendicular shots. The pixel size of the DOP on the ground is by default 0.4 m x 0.4 m, since 2007 even 0.2 m x 0.2 m. They are coloured, sharp and as precise as a map. Digital orthophotos are scale-width and can thus be compared directly with maps of the same scale or digitally combined with specialist data, for example road planning. Since 2008, an infrared channel has also been recorded in the creation of the digital orthophotos and offered in various forms: Characteristics RGBI: Representation together with the three color channels of the normal orthophoto; Type of CIR: Representation of the infrared channel along with the red and green channel of the normal DOP; Type of IR: Representation of the infrared channel only数字正射影像（Digital orthophotos，DOPs）是具备高分辨率、无畸变的地球表面影像。自2001年起，其通过计算机化匀色处理流程由航空影像制作而成，几何精度约为±0.4米，常规比例尺为1:**，涵盖12000张垂直摄影影像。该类数字正射影像的地面像素尺寸默认设置为0.4米×0.4米，自2007年起更可低至0.2米×0.2米。其色彩饱满、画面清晰，精度可与专业地图媲美。数字正射影像具备比例尺一致性，因此可直接与相同比例尺的地图进行比对，或与专业数据（如道路规划数据）进行数字化融合。 自2008年起，数字正射影像的制作流程中新增了红外通道，并提供以下三种形式的产品： - RGBI型：融合红外通道与常规正射影像的三个色彩通道的合成影像； - CIR型：包含常规数字正射影像的红、绿通道与红外通道的彩红外影像； - IR型：仅包含红外通道的单通道影像。