Geospatial Information Production is the process whereby the topographic features of the Kingdom of Saudi Arabia,are collected from various sources and processes, and compiled into specification compliant geoinformation products.
GASGI compiles these topographic features from a variety of different sources, including stereo aerial and satellite imagery, GPS coordinates obtained in the field, and authoritative supplementary data. Examples of the features currently available in GASGI databases are:
- Terrain features such as sand, gravel, etc.
- Water features such as coastlines, wadis (dry watercourses) etc.
- Man-made features such as roads, buildings, walls and fences, etc.
The horizontal and vertical coordinates of these features are obtained by photogrammetrically measuring stereo aerial or satellite images. These results are verified and classified in the field, and additional information that was not visible during the photogrammetric process is also collected via GPS. New geographical names are also gathered in the field and added to the existing names database for labelling these topographic features.
The clear and unambiguous representation of these topographic features on a map, is realized by a cartographic process, which is both an art and a science. The map scale and specification define the map content, accuracy and overall appearance. This process converts topographic data into topographic map information.
GASGI also produces topographic and image maps data in other scales, such as the 1:2,000,000 scale National Reference Map.