The centroid method is a common procedure for subpixel location that is applied to a large number of optical sensors. In practice, it is always accompanied by thresholding algorithms used to eliminate undesirable background that may decrease precision. We present a full analytical description of the interaction between centroiding and thresholding applied over an intensity distribution corrupted by additive Gaussian noise. An in depth analysis of the most outstanding statistical properties of this relation (mean and variance) is also presented by means of simulated and experimental data. This work provides fundamental concepts to the designers of sensors that are based on centroid measurements to allow them to use thresholding correctly before centroid computation.
© 2004 Optical Society of America
Original Manuscript: April 16, 2004
Manuscript Accepted: July 17, 2004
Published: November 1, 2004
Jorge Ares and Justo Arines, "Influence of thresholding on centroid statistics: full analytical description," Appl. Opt. 43, 5796-5805 (2004)