National Instruments NI-IMAQ - Manual (Page 48)

Glossary
NI-IMAQ for IEEE-1394 Cameras User Manual G-6 ni.com
O
operating system Base-level software that controls a computer, runs programs, interacts with
users, and communicates with installed hardware or peripheral devices.
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 132 Mbytes/s.
picture aspect ratio The ratio of the active pixel region to the active line region. For standard
video signals like RS-170 or CCIR, the full-size picture aspect ratio
normally is 4/3 (1.33).
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 aspect ratio The ratio between the physical horizontal size and the vertical size of the
region covered by the pixel. An acquired pixel should optimally be square,
thus the optimal value is 1.0, but typically it falls between 0.95 and 1.05,
depending on camera quality.
protocol The exact sequence of bits, characters, and control codes used to transfer
data between computers and peripherals through a communications
channel.
pts Points.
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.