Share Email Print

Proceedings Paper

Dependence of adaptive cross-correlation algorithm performance on the extended scene image quality
Author(s): Erkin Sidick
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Recently, we reported an adaptive cross-correlation (ACC) algorithm to estimate with high accuracy the shift as large as several pixels between two extended-scene sub-images captured by a Shack-Hartmann wavefront sensor. It determines the positions of all extended-scene image cells relative to a reference cell in the same frame using an FFT-based iterative image-shifting algorithm. It works with both point-source spot images as well as extended scene images. We have demonstrated previously based on some measured images that the ACC algorithm can determine image shifts with as high an accuracy as 0.01 pixel for shifts as large 3 pixels, and yield similar results for both point source spot images and extended scene images. The shift estimate accuracy of the ACC algorithm depends on illumination level, background, and scene content in addition to the amount of the shift between two image cells. In this paper we investigate how the performance of the ACC algorithm depends on the quality and the frequency content of extended scene images captured by a Shack-Hatmann camera. We also compare the performance of the ACC algorithm with those of several other approaches, and introduce a failsafe criterion for the ACC algorithm-based extended scene Shack-Hatmann sensors.

Paper Details

Date Published: 26 August 2008
PDF: 11 pages
Proc. SPIE 7093, Advanced Wavefront Control: Methods, Devices, and Applications VI, 70930G (26 August 2008); doi: 10.1117/12.793005
Show Author Affiliations
Erkin Sidick, Jet Propulsion Lab. (United States)

Published in SPIE Proceedings Vol. 7093:
Advanced Wavefront Control: Methods, Devices, and Applications VI
John D. Gonglewski; Richard A. Carreras; Troy A. Rhoadarmer, Editor(s)

© SPIE. Terms of Use
Back to Top