ABSTRACT
Photogrammetry is the science or art of obtaining reliable measurements by means of photographs (McGlone et al., 2004). Although the practice of photogrammetry is most commonly applied to aerial photography, its principles apply to other photographs and, by extension, to images collected by other instruments, including the remote-sensing systems described in Chapter 18. Chapter 4 provides an introduction to the concepts and algorithms used in photogrammetry. The practice of photogrammetry yields positional information extracted from the aerial imagery. The elevation information is sometimes used to compile large-scale topographic maps.
