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Introduction
In
a constantly changing industry, DVI is the next major attempt at an all-in-one,
standardized, universal connector for audio/video applications. Featuring a modern
design and backed by the biggest names in the electronic industry, DVI is set
to finally unify all digital media components with a single cable, remote, and
interface.
DVI is built with a 5 Gbps bandwidth limit, over twice that of
HDTV (which runs at 2.2 Gbps), and is built forwards-compatible by offering unallocated
pipeline for future technologies. The connectors are sliding contact (like FireWire
and USB) instead of screw-on (like DVI), and are not nearly as bulky as most current
video interfaces.
The screaming
bandwidth of HDMI is structured around delivering the highest-quality digital
video and audio throughout your entertainment center. Capable of all international
frequencies and resolutions, the HDMI cable will replace all analog signals (i.e.
S-Video, Component, Composite, and Coaxial), as well as HDTV digital signals (i.e.
DVI, P&D, DFP), with absolutely no compromise in quality.
Additionally,
HDMI is capable of carrying up to 8 channels of digital-audio, replacing the old
analog connections (RCA, 3.5mm) as well as optical formats (SPDIF, Toslink).
VIDEO INTERFACES Video
Graphics Array (VGA) is an analog computer display standard first marketed in
1987 by IBM. While it has been obsolete for some time, it was the last graphical
standard that the majority of manufacturers decided to follow, making it the lowest
common denominator that all PC graphics hardware supports prior to a device-specific
driver being loaded. For example, the Microsoft Windows splash screen appears
while the machine is still operating in VGA mode,
which is the reason that this screen always appears in reduced resolution and
color depth.
The term VGA is often used
to refer to a resolution of 640×480, regardless of the hardware that produces
the picture. It may also refer to the 15-pin D-subminiature VGA connector which
is still widely used to carry analog video signals of all resolutions.
VGA
was officially superseded by IBM's XGA standard, but in reality it was superseded
by numerous extensions to VGA made by clone manufacturers that came to be known
as "Super VGA".
A Male DVI-I
Plug
The DVI interface uses a digital protocol in which the desired brightness
of pixels is transmitted as binary data. When the display is driven at its native
resolution, all it has to do is read each number and apply that brightness to
the appropriate pixel. In this way, each pixel in the output buffer of the source
device corresponds directly to one pixel in the display device, whereas with an
analog signal the appearance of each pixel may be affected by its adjacent pixels
as well as by electrical noise and other forms of analog distortion.
Previous
standards such as the analog VGA were designed for CRT-based devices and thus
did not use discrete time. As the analog source transmits each horizontal line
of the image, it varies its output voltage to represent the desired brightness.
In a CRT device, this is used to vary the intensity of the scanning beam as it
moves across the screen.
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