Glossary
G-10
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pixel count
The total number of pixels between two horizontal synchronization signals.
The pixel count determines the frequency of the pixel clock.
PLL
Phase-locked loop. Circuitry that provides a very stable pixel clock that
is referenced to another signal, for example, an incoming horizontal
synchronization signal.
protocol
The exact sequence of bits, characters, and control codes used to transfer
data between computers and peripherals through a communications
channel.
pts
Points.
PXI
PCI eXtensions for Instrumentation. An open specification that builds on
the CompactPCI specification by adding instrumentation-specific features.
R
RAM
Random-access memory.
real time
A property of an event or system in which data is processed as it is acquired
instead of being accumulated and processed at a later time.
relative accuracy
A measure in LSB of the accuracy of an ADC; it includes all nonlinearity
and quantization errors but does not include offset and gain errors of the
circuitry feeding the ADC.
resolution
The smallest signal increment that can be detected by a measurement
system. Resolution can be expressed in bits, in proportions, or in percent of
full scale. For example, a system has 12-bit resolution, one part in 4,096
resolution, and 0.0244 percent of full scale.
RGB
Color encoding scheme using red, green, and blue (RGB) color information
where each pixel in the color image is encoded using 32 bits: 8 bits for red,
8 bits for green, 8 bits for blue, and 8 bits for the alpha value (unused).
ribbon cable
A flat cable in which the conductors are side by side.
ROI
Region of interest. A hardware-programmable rectangular portion of the
acquisition window.
ROM
Read-only memory.
RS-170
The U.S. standard used for black-and-white television.
