Paper
23 December 2002 Deconvolution in line scanners using a priori information
Bernhard Wirnitzer, Tadeo Spraggon-Hernandez
Author Affiliations +
Abstract
In a digital camera the MTF of the optical system must comprise a low-pass filter in order to avoid aliasing. The MTF of incoherent imaging usually and in principle is far from an ideal low-pass. Theoretically a digital ARMA-Filter can be used to compensate for this drawback. In praxis such deconvolution filters suffer from instability because of time-variant noise and space-variance of the MTF. In addition in a line scanner the MTF in scan direction slightly differs in each scanned image. Therefore inverse filtering will not operate satisfactory in an unknown environment. A new concept is presented which solves both problems using a-priori information about an object, e.g. that parts of it are known to be binary. This information is enough to achieve a stable space and time-variant ARMA-deconvolution filter. Best results are achieved using non linear filtering and pattern feedback. The new method was used to improve the bit-error-rate (BER) of a high-density matrix-code scanner by more than one order of magnitude. An audio scanner will be demonstrated, which reads 12 seconds of music in CD-quality from an audio coded image of 18mm×55mm size.
© (2002) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Bernhard Wirnitzer and Tadeo Spraggon-Hernandez "Deconvolution in line scanners using a priori information", Proc. SPIE 4792, Image Reconstruction from Incomplete Data II, (23 December 2002); https://doi.org/10.1117/12.451790
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Deconvolution

Digital filtering

Electronic filtering

Image filtering

Scanners

Filtering (signal processing)

Modulation transfer functions

RELATED CONTENT

Adaptation of gray-scale morphological filters
Proceedings of SPIE (May 21 1993)
New hardware implementation of fast vector median filters
Proceedings of SPIE (October 22 1993)
Mixed median filters and their properties
Proceedings of SPIE (April 04 1997)
Fuzzy stack filtering under structural constraints
Proceedings of SPIE (March 05 1999)
Joint target-detection and tracking smoothers
Proceedings of SPIE (May 11 2009)

Back to Top