Effective noise in thresholded intensity distribution: influence on centroid statistics

Abstract

It is usual to preprocess data before reduction, but it is not so common to study how this operation affects the final results. Determination of the centroid is a relevant task for many optical measurement devices, and the centroid is very often calculated over thresholded data. The influence of preprocessing thresholding algorithms on the statistical properties of intensity data affected by additive Gaussian noise is described as a different effective additive signal perturbation. Theoretical, simulated, and experimental analyses of the model of the effective noise were performed, and good agreement among the analyses was obtained. Direct extension of the analyses from the influence of preprocessing to centroid determination is also presented.

Anisotropic Fiber Bragg Gratings Inscribed by High-Intensity Femtosecond-UV Pulses: Manufacturing Technology and Strain Characterization for Sensing Applications

“…A threshold cut was not used, as the threshold operation can introduce errors when data points are close to the threshold level [32]. Instead, a window of points was taken.…”

Changes of ocular aberrations with gaze

“…There is also an extrinsic fluctuation contributing to the measured changes, due to random eye movements, different initial pupil positioning between measurement series (Davies et al. , 2003), and measurement noise due to the centroiding algorithms and the detector noise (Ares and Arines, 2001, 2004). Our results (see ) show that there is a high inter‐series variability of aberrations for a fixed gaze, which diminishes the signal‐to‐noise ratio for the detection of gaze‐related aberration changes.…”

Hartmann and Hartmann-Shack spot identification and centroid evaluation by a new efficient segmentation and thresholding algorithm

“…[12][13][14][15][16] The thresholding method is the operation on the continuous intensity distribution I x,y as a nonlinear transformation to Iu x,y described in Eq. 1.…”