National Instruments Image Acquisition Software User Manual
Page 57
Glossary
G-6
©
National Instruments Corporation
function
a set of software instructions executed by a single line of code that may
have input and/or output parameters and returns a value when executed;
examples of functions are:
y = COS (x)
status =
AO_config
(board, channel, range)
G
gamma
the nonlinear change in the difference between the video signal’s brightness
level and the voltage level needed to produce that brightness
genlock
circuitry that aligns the video timing signals by locking together the
horizontal, vertical, and color subcarrier frequencies and phases and
generates a pixel clock to clock pixel data into memory for display or into
another circuit for processing
GND
ground signal
GUI
graphical user interface—an intuitive, easy-to-use means of
communicating information to and from a computer program by means of
graphical screen displays; GUIs can resemble the front panels of
instruments or other objects associated with a computer program.
H
h
hour
hardware
the physical components of a computer system, such as the circuit boards,
plug-in boards, chassis, enclosures, peripherals, cables, and so on
HSYNC
horizontal sync signal—the synchronization pulse signal produced at the
beginning of each video scan line that keeps a video monitor's horizontal
scan rate in step with the transmission of each new line
HSYNCIN
horizontal sync input signal
hue
represents the dominant color of a pixel. The hue function is a continuous
function that covers all the possible colors generated using the R, G, and B
primaries. See also RGB.
Hz
hertz—the number of scans read or updates written per second
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