Reconstructing Images of Bar Codes for Construction Site Object Recognition.
Reconstructing Images of Bar Codes for Construction Site
Gilsinn, D. E.; Cheok, G. S.; O'Leary, D. P.
NIST SP 989; September 2002.
International Symposium on Automation and Robotics in
Construction, 19th (ISARC). Proceedings. National
Institute of Standards and Technology, Gaithersburg,
Maryland. September 23-25, 2002, 363-368 pp, 2002.
Available from: Superintendent of Documents, U.S.
Government Printing Office, Mail Stop SSOP, Washington,
Order number: PB2002-108230
robotics; construction; bar codes; image processing
This paper discusses a general approach to
reconstructing ground truth intensity images of bar
codes that have been distorted by LADARoptics. The first
part of this paper describes the experimental data
collection of several bar code images along with
experimental estimates of the LADAR beam size and
configuration at various distances from the source.
Mathematical models of the beam size and configuration
were developed and were applied through a convolution
process to a simulated set of bar code images similar to
the original experiment. This was done in order to
estimate beam spread models (beam spread models are
unique to each specific LADAR) to be used in a
deconvolution process to reconstruct the original bar
code images from the distorted images. In the
convolution process a distorted image in vector form g
is associated with a ground truth image f and each
element of g is computed as a weighted average of
neighboring elements of f to that associated element.
The deconvolution process involves a least squares
procedure that approximately solves a matrix equation of
the form Hf = g where H is a large sparse matrix that is
made up of elements from the beam spread function.