21 September 2007 Refocusing of defocused images using SAR2 algorithm
Author Affiliations +
This paper utilizes the methodology of SAR2 algorithm, a two dimensional variant of the ω-k algorithm, to refocus out-of-focus images. Refocusing of images may be necessary in machine vision as a preprocessing step before edge detection or image segmentation in the imaging and manipulation of 3D objects. The SAR2 algorithm generates a complex amplitude distribution and the corresponding point spread function in a manner similar to Fraunhofer diffraction distribution model and its point spread function as seen in Fourier optics. The matched filter utilized in the SAR2 algorithm has a focus-in-altitude interpretation and may be varied to increase or decrease the radius of out-of-focus blur associated with a particular point spread function of scatterers of various heights. This paper demonstrates focusing of a line object L={1 : x=y;-≤x≤63; -64≤y≤63}. Although a rectangular aperture is used in the refocusing process, other apertures may also be used such as circular or Gaussian.
© (2007) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jehanzeb Burki, Christopher F. Barnes, "Refocusing of defocused images using SAR2 algorithm", Proc. SPIE 6697, Advanced Signal Processing Algorithms, Architectures, and Implementations XVII, 66970D (21 September 2007); doi: 10.1117/12.735343; https://doi.org/10.1117/12.735343

Back to Top