It is important to note that remote sensing images do not have geometric properties as a map and, therefore, there is the need to apply specific techniques suc as georeferencing and geocoding to ensure that remote sensing (RS) images correspend with to the position on the ground. This learning path seeks to introduce you to these techniques for their proper applications. It must be noted here that the "position on the ground" can either be defined in a 3D terrain coordinate system or through a map projection in a 2D map coordinate system.
In this learning path, we start with the terminology known as Georeferening and its process involves two steps: 1. selection of the appropriate type of transformation ; and 2. determination of the transformation paramters.
Ground Control Points (GCPs) which help in the determination of transformation parameters in the process of georeferencing is our next item of discussion. GCPs are points that can be clearly identified in the image and on the target map.
Apart from the elements of georeferencing and GCPs in this learning path, another element which is key for our discussion is Geocoding. Geocoding enables us to produce a new image from an RS image such that it fits a specific map projection.