Image data - Landsat

Land application products for Central Africa from OSFAC (Observatoire Satellital des Forêts d'Afrique Centrale). Landsat L1T (terrain corrected) data from the Landsat 7 satellite. The Level 1T (L1T) data product provides systematic radiometric and geometric accuracy by incorporating ground control points, while also employing a Digital Elevation Model (DEM) for topographic accuracy. Geodetic accuracy of the product depends on the accuracy of the ground control points and the resolution of the DEM used. All Landsat 7 scenes collected since May of 2003 have data gaps. Although the scenes have only 78 percent of their pixels, these data are still some of the most geometrically and radiometrically accurate of all civilian satellite data in the world.本数据集为OSFAC（中非森林卫星观测站，Observatoire Satellital des Forêts d'Afrique Centrale）面向中非地区推出的土地应用产品，所用数据源自Landsat 7卫星的Landsat L1T（地形校正）数据。该Level 1T（L1T）数据产品通过引入地面控制点实现系统化辐射与几何精度保障，并结合数字高程模型（DEM，Digital Elevation Model）提升地形校正精度。该产品的大地测量精度取决于所用地面控制点的精度以及所采用数字高程模型的分辨率。自2003年5月起获取的所有Landsat 7景影像均存在数据缺口，尽管单景影像仅保留78%的有效像素，但该类数据仍是全球民用卫星影像中几何与辐射精度顶尖的数据集之一。