SfM (Structure from Motion)
Definition
A photogrammetric method that builds a 3D point cloud and orthomosaic from overlapping images by computing camera positions and feature matches. Standard processing pipeline for UAV survey data.
Related terms
- Crop mark
- A differential growth or colour pattern in surface vegetation caused by a sub-surface soil change, including disturbance from digging, which alters moisture...
- Multi-temporal analysis
- Comparison of imagery acquired at different dates to detect change. A soil disturbance present in a 2009 image but absent in 2005...
- NDVI
- Normalised Difference Vegetation Index. Computed as (NIR-Red)/(NIR+Red) from multispectral imagery. Values near 1 indicate dense healthy vegetation; values near 0 indicate bare...
- Orthomosaic
- A geometrically corrected image assembled from many overlapping photographs, with a consistent scale across its extent. UAV-derived orthomosaics can be georeferenced to...
- UNOSAT
- The UNODC Satellite Centre, a UN programme that provides satellite-derived analysis in support of humanitarian and legal investigations, including imagery used for...
Explained in
- Aerial and Satellite Remote SensingA photogrammetric method that builds a 3D point cloud and orthomosaic from overlapping images by computing camera positions and feature matches. Standard proce...