System information

Glossary-2 Vicon MX Hardware System Reference
Aspect ratio The proportional width
and height of a picture, expressed in the
format w:h.
Autolabel A process by which Vicon
application software applies a previously
generated autolabel calibration to a saved
trial, identifies individual marker trajecto-
ries, and labels them automatically.
During this offline processing, the Vicon
application software compares the
reconstructed 3D markers in the
3D Workspace to the marker locations
that the autolabel calibration process
stored in the .sp or .vsk file for the
subject. Also see Autolabel calibration,
Marker, .sp file, Subject calibration, and
.vsk file.
Autolabel calibration A process by
which some Vicon application software
identifies the relationship between the
labels defined in the marker (.mkr) or
Vicon skeleton template (.vst) file
associated with a subject and the
reconstructed 3D markers captured in a
trial.
During this offline processing, the Vicon
application software stores the marker
locations in the subject parameters (.sp)
or Vicon skeleton (.vsk) file. The Vicon
application software can then apply this
autolabel calibration to that subject in
subsequent trials.
Some Vicon application software uses the
subject calibration process instead. Also
see Autolabel, .mkr file, Pipeline, .sp file,
Subject calibration, .vsk file, .vst file, and
Workstation.
.avi file Audio Video Interleaved file. A
Microsoft Windows binary file with
extension .avi, which combines
multimedia sound and moving picture
data in a single stream in the Microsoft
RIFF (Resource Interchange File Format)
format. Vicon application software can
play—and optionally generate—.avi files.
Additional compressor/decompressor
(codec) software may be required for
certain .avi files. Also see Reference
video.
B
Band-pass filter A filter that permits
only signals within a specified range of
frequencies to be passed through. Some
Vicon cameras are fitted with band-pass
interference optical filters that allow the
specific wavelengths of light emitted by
the Vicon strobe units to pass. Also see
Low-pass filter, MX Camera, and Strobe
unit.
Blob In Vicon V-series systems, a
continuous area of above-threshold data
from the camera. Blobs are submitted as
candidates to Vicon circle-fitting
algorithms to determine which are likely
to be markers. Also see Grayscale blob.
Blooming The defocusing of a picture
due to excessive brightness. This can
occur when a Vicon marker is close to a
camera with high sensitivity or whose
aperture is too wide. This can be resolved
by altering sensitivity and/or the aperture
or possibly by moving the camera. Also
see Aperture and Marker.
BNC connector British Naval
Connector (BNC). A durable cable
connector that transfers signals between
devices. It connects with a push and a
twist. Also see LEMO® connector.
BOB Break Out Box. A hardware unit in
Vicon V-series systems used to connect
one to three cameras to a single port on
the Datastation. Also referred to as a
Camera Interface Unit. Also see
Datastation.
BodyBuilder Vicon application software
for kinematic and kinetic modeling, which
reduces complex 3D vector algebra into a
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