Glossary

A glossary of terms used throughout this guide:

DSM

Digital Surface Model. A modelling of a an area that include foliage and structures.

DTM

Digital Terrrain Model. Similar to DSM but excluding foliagge and other structures. Also Displacement Tracking Matrix, an IOM initiative that gathers data on mobility, vulnerability and needs.

Drone

Common term for unmanned or remotely-piloted aircraft.

Georeferencing

The act of aligning geographic data (such as a map) to a known coordinate system.

GIS

Geographic information system. In general terms, a system that is designed to manipulate, store, analyze, and manage spatial and geographic data.

GSD

Ground sample distance. The resolution of an aerial image

IOM

International Organization for Migration.

Nadir

In aerial photography, the point on the ground that lies directly below the perspective center of the camera lens; also, images taken from this perspective (i.e., straight down).

Orthomosaic

A two-part process in which a number of images are combined together or “stitched” into a single image and also corrected for distortion.

Orthorectification

A process of removing the efects of image perspective and relief efects by using camera model information and elevation data, creating a fnal image that has a constant scale.

RTK

Real time kinematic. A technique used to extract more-precise-than-normal position data from global satellite navigation timing signals.

UAV

Unmanned Aerial Vehicle, commonly known as a drone. Radio controlled fixed-wing or rotorcraft.