Spectral method for calculating pixel overlap areas applied to multiframe image de-aliasing

Edward Cohen; Richard H. Picard; Peter N. Crabtree

doi:10.1117/12.2059221

18 September 2014 Spectral method for calculating pixel overlap areas applied to multiframe image de-aliasing

Edward Cohen, Richard H. Picard, Peter N. Crabtree

Proceedings Volume 9227, Unconventional Imaging and Wavefront Sensing 2014; 922704 (2014) https://doi.org/10.1117/12.2059221
Event: SPIE Optical Engineering + Applications, 2014, San Diego, California, United States

Abstract

Various techniques and algorithms have been developed to improve the resolution of sensor-aliased imagery captured with an under-sampled pixelated image plane. In the literature these de-aliasing algorithms are sometimes included under the broad umbrella of super-resolution. One basic approach to multiframe de-aliasing is the well-known noniterative algorithm termed variable pixel linear reconstruction (VPLR) or “drizzling.” Many modern techniques are based on iterative optimization of a forward model (objective function). Regardless, both iterative and noniterative techniques rely on estimation of frame-to-frame displacements and rotations to subpixel accuracy. Weights are then solved for and used to distribute low-resolution (LR) pixel values to a high-resolution (HR) grid. One approach used in both VPLR and iterative methods to determine weights is to calculate pixel overlap areas. Well-known spatial domain approaches based on computational geometry exist to perform such calculations. Here we present a novel approach based on exactly calculating overlap areas in the spectral domain, which we call the spectral-overlap (SO) method, and include a comparison with the geometric approach of O’Rourke. All spatial spectra in the SO method are calculated analytically once and for all, resulting in expressions devoid of quadratures. Initial studies indicate that this new algorithm executes about 20 times faster than using the O’Rourke algorithm. The speedup is partly explained by the ability to precompute many quantities involved in the SO approach and apply these quantities to the computation of many distinct spatial overlaps. Application of the algorithm to multiframe de-aliasing is demonstrated using simulated imagery.

Citation Download Citation

Edward Cohen, Richard H. Picard, and Peter N. Crabtree "Spectral method for calculating pixel overlap areas applied to multiframe image de-aliasing", Proc. SPIE 9227, Unconventional Imaging and Wavefront Sensing 2014, 922704 (18 September 2014); https://doi.org/10.1117/12.2059221

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available