1.
Brief Introduction
Terms and Definitions
CP 3072 User Manual 19
transfer rate. This is a 10-bit, scrambled, polarity independent
interface with common scrambling for both component ITU-R 601 and
composite digital video and four channels of (embedded) digital audio.
“Seamless Switching”:
A feature found on many video switchers. This
feature causes the switcher to wait until the vertical interval to switch.
This avoids a glitch (temporary scrambling) which normally is seen
when switching between sources.
“SMPTE”:
Society of Motion Picture and Television Engineers. A global
organization, based in the United States that sets standards for base
band visual communications. This includes film as well as video and
television standards.
“USB”:
Universal Serial Bus. USB was developed by seven PC and
telecom industry leaders (Compaq, DEC, IBM, Intel, Microsoft, NEC,
and Northern Telecom). The goal was easy plug-and-play expansion
outside the box, requiring no additional circuit cards. Up to 127
external computer devices may be added through a USB hub, which
may be conveniently located in a keyboard or monitor. USB devices
can be attached or detached without removing computer power. The
number of devices being designed for USB continues to grow, from
keyboards, mice, and printers to scanners, digital cameras, and ZIP
drives.
“VESA”:
Video Electronics Standards Association. A nonprofit number
organization dedicated to facilitating and promoting personal computer
graphics through improved standards for the benefit of the end-user.
“VGA”:
Video Graphics Array. Introduced by IBM in 1987, VGA is an
analog signal with TTL level separate horizontal and vertical sync. The
video outputs to a 15-pin HD connector and has a horizontal scan
frequency of 31.5 kHz and vertical frequency of 70 Hz (Mode 1, 2) and
60 Hz (Mode 3). The signal is non-interlaced in modes 1, 2, and 3 and
interlaced when using the 8514/A card (35.5 kHz, 86 Hz) in mode 4. It
has a pixel by line resolution of 640×480 with a color palette of 16 bits
and 256,000 colors.
