European Facility For Airborne Research April 4, 2025, 16:19
gain: A general term used to denote an increase in signal power in transmission from one point to another. Gain is usually expressed in decibels.
geolocation: The correspondence between position in an image and position in a geographic reference system.
geometric correction: The process of determining the geolocation of an image pixel or other data.
georeference-able: Data set for which information for the geolocation of each data element is available but not applied, so that the data set geometry is not compatible with a geographical representation such as a map.
georeferenced: Data set for which the geolocation of each data element is known.
georeferencing: see geometric correction.
ground control point (GCP): A geographic feature of known location that is recognizable on images to use them for rectification or other geometric corrections.
ground sampling distance (GSD): The distance from centroid to centroid between adjacent spatial samples on the earth’s surface corresponding to respective detector pixels.
ground truth: Observations made on the ground at a site that is being imaged from space/air for the purpose of verifying either the absolute radiometric and/or geometric calibration of the imagery or the classified product from the image.
ground track: The vertical projection of the actual flight path of an aerial or space vehicle onto the surface of the Earth.