Glossary
NI PXI/PCI-1411 User Manual G-4 ni.com
E
EEPROM Electrically erasable programmable read-only memory. ROM that can be
erased with an electrical signal and reprogrammed.
external trigger A voltage pulse from an external source that triggers an event such as
A/D conversion.
F
field For an interlaced video signal, a field is half the number of horizontal
linesneeded to represent a frame of video. Th e first field of a frame
contains all the odd-numbered lines, the second field contains all of the
even-numbered lines.
FIFO First-in first-out memory buffer. The first data stored is the first data sent
to the acceptor; FIFOs are used on image acquisition devices to temporarily
store incoming data until that data can be retrieved.
frame A complete image. In interlaced formats, a frame is composed of two fields.
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.
H
HSI Color encoding scheme in Hue, Saturat ion, and Intensity.
HSL Color encoding scheme using Hue, Saturation, and Luma information
where each image in the pixel is encoded using 32 bits: 8 bits for hue,
8 bits for saturation, 8 bits for luma, and 8 unused bits.