France: Airbus Defence and Space has expanded its WorldDEM portfolio with the launch of WorldDEM4Ortho. Tailored for orthorectification of high and very high resolution optical and radar satellite data, WorldDEM4Ortho will enable corrections of all distortions induced by the topographical variations of the Earth’s surface and satellite orientation when acquiring an image.
WorldDEM4Ortho covers the Earth’s entire land surface and is one of the most consistent and accurate elevation models for orthorectification on a global scale.
Without these geometrical corrections, satellite images cannot be used in GIS or for any mapping related applications.
With the huge development of new geo-located applications like business analytics, location-based services or tourism, the needs for such a consistent and precise elevation model are exploding.
WorldDEM4Ortho is based on the global WorldDEM dataset. It is produced via a fully automated process and features a vertical accuracy of four meters in a 24 meter raster. Identified disturbing terrain artefacts are removed.
Bodies of water like lakes or sea are flattened. Rivers are stepped with a flow that follows the surrounding shorelines. Adaptive smoothing processes are also applied to different landscapes and land-use such as urban areas to avoid distortions in the orthorectified image.