Glossary
©NationalInstruments Corporation G-3 NI-IMAQfor IEEE-1394 Cameras User Manual
driver Softwarethat controls a specific hardware device, such as an IMAQ or
DAQdevice.
E
externaltrigger A voltagepulse from an external source that trig gers an eventsuch as
A/D conversion.
F
field Foran interlaced video signal, a field is half the number of horizontal lines
neededto represent a frame of video. The first field of a frame contains all
theodd-numbered lines, the second field contains all ofthe even-numbered
lines.
frame Acomplete image. In interlaced formats, a frame is composed of two fields.
function A set of software instructions executed bya sin gle line of code that may
haveinput and/or output parameters and returns a value when executed.
G
gamma The nonlinear change in the difference between the video signal’s
brightness leveland the voltage level needed to produce that brightness.
GUI Graphical user interface. An intuitive, easy-to-use means of
communicating informationto and from a computer program by means
ofgraphical screen displays. GU Is can resemble the front panelsof
instruments or other objects associated with a computer program.
H
hardware Thephysical components of a computer system, such as the circuit boards,
plug-in boards, chassis, enclosures, peripherals, and cables.
hue Representsthe dominan tco lor of a pixel. The hue function is a continuous
functionthat covers all the possible colors generated using the R, G, and B
colorspectrum. See also RGB.
Hz Hertz.Frequ encyin units of 1/second.