Glossary
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National Instruments Corporation
G-3
P
PCI
Peripheral Component Interconnect. A high-performance expansion bus
architecture originally developed by Intel to replace ISA and EISA. PCI
offers a theoretical maximum transfer rate of 133 Mbytes/s.
pixel
Picture element. The smallest division that makes up the video scan line;
for display on a computer monitor, a pixel’s optimum dimension is square
(aspect ratio of 1:1, or the width equal to the height).
pixel clock
Divides the incoming horizontal video line into pixels.
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.
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: eight bits for
red, eight bits for green, eight bits for blue, and eight bits for the alpha value
(unused).
ROI
Region of interest. A hardware-programmable rectangular portion of the
acquisition window.
RTSI bus
Real-Time System Integration Bus. The National Instruments timing bus
that connects image acquisition and DAQ devices directly, by means of
connectors on the devices, for precise synchronization of functions.
S
scatter-gather DMA
A type of DMA that allows the DMA controller to reconfigure on-the-fly.
SDRAM
Synchronous dynamic RAM.
