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Video, Glossary (continued) – D-Link DSM-320 User Manual

Page 106

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106

Video

AVI: Short for Audio Video Interleave, the

file format

for

Microsoft’s

Video for

Windows

standard

. See under

Video for Windows

.

DivX: Is a video format that is MPEG-4 compliant and widely used on the
Internet for encoding video files.

MPEG: Short for Moving Picture Experts Group, and pronounced “empeg”.
MPEG generally produces better-quality

video

than competing formats. MPEG

achieves high

compression

rate by storing only the changes from one

frame

to

another, instead of each entire frame. MPEG uses a type of lossy compression,
since some data is removed. However, the reduction in the resulting video
quality is minimal. There are three major MPEG standards: MPEG-1, MPEG-2
and MPEG-4.

The most common implementations of the MPEG-1 standard provide a
video

resolution

of 352-by-240 at 30

frames per second

(fps). MPEG-1

is used with Video CDs (VCD) and results in video quality slightly below
the quality of a VCR video.

MPEG-2 offers higher resolution with CD-quality audio. This is sufficient
for all major TV standards, including

NTSC

, and even

HDTV

. MPEG-2

is used by

DVDs

. MPEG-2 compresses a 2 hour video into a few

gigabytes of data on a single disc.

MPEG-4 is a video compression standard based on MPEG-1 and
MPEG-2. Videos encoded with MPEG-4 technology are considerably
smaller than videos encoded with MPEG-1 or 2. MPEG-4 was
standardized in October 1998.

QuickTime: An audio and video compression technology developed by Apple
Computer and is widely supported on Macintosh and Windows PC computers.
The latest QuickTime implementation is MPEG-4 compliant.

XviD: XviD is an ISO MPEG-4 compliant video codec. It’s an open source
project which is developed and maintained by many people from all over the
world.

Glossary (continued)