Adequacy of pseudo-direct georeferencing of terrestrial laser scanning data for coastal landscape surveying against indirect georeferencing

• Main Authors: Marion Jaud, Pauline Letortu, Emmanuel Augereau, Nicolas Le Dantec, Mickaël Beauverger, Véronique Cuq, Christophe Prunier, Réjanne Le Bivic, Christophe Delacourt
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2017-01-01
• Series: European Journal of Remote Sensing
• Subjects: Terrestrial laser scanning; coastal monitoring; direct georeferencing; indirect georeferencing; multi-temporal surveys; geomorphological evolution
• Online Access: http://dx.doi.org/10.1080/22797254.2017.1300047

The georeferencing process is crucial to the accuracy of terrestrial laser scanner (TLS) data, in particular in the context of diachronic studies relying on multi-temporal surveys. The use of Ground Control Points in the georeferencing process can however be complex when confronted with the practical constraints of coastal surveying. A simple and quick alternative method called “pseudo-direct georeferencing” is proposed in the present paper. This method involves internal inclinometers to measure roll and pitch angles and a centimetric GPS to measure the position of the TLS center and the position of one backsight target. When assessing the transformational uncertainty by using a set of independent ground validation points for both classical indirect and proposed pseudo-direct methods, we respectively obtain root mean square errors of 4.4 cm for the indirect method and 3.8 cm for the pseudo-direct method.