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Metrological Evaluation of Contrast Target Center Algorithm for Terrestrial Laser Scanners



Prem K. Rachakonda, Balasubramanian Muralikrishnan, Daniel S. Sawyer


Contrast targets are used with Terrestrial Laser Scanners, typically for long range scanning and registering multiple scans in a scene. These targets are very simple in construction and inexpensive to fabricate. Some original equipment manufacturers (OEM) provide software to determine the center of contrast targets, but many end-users use third party software to perform post-processing and is a challenging task. Further, different OEM software may produce different target centers for the same target dataset. In this context, this paper describes and evaluates a novel algorithm developed at the National Institute of Standards & Technology (NIST), to calculate the center of a contrast target and compares its performance in various scan conditions. To our knowledge, no known algorithm exists in open literature for this purpose and is the motivation for this work.


contrast targets, checkerboard targets, laser scanners, TLS, documentary standards


Rachakonda, P. , Muralikrishnan, B. and Sawyer, D. (2018), Metrological Evaluation of Contrast Target Center Algorithm for Terrestrial Laser Scanners, Measurement, [online], (Accessed May 26, 2024)


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Created October 26, 2018