24 GLOSSARY
Glossary
Bit rate
Value indicating the amount of video data
compressed in a DVD per second. The unit is
Mbps (megabit per second). 1 Mbps indicates
that the data per second is 1,000,000 bits. The
higher the bit rate, the larger the amount of
data. However, this does not always mean higher
quality pictures.
Chapter
Sections of a picture or a music piece on a DVD
that are smaller than titles. Many titles are
composed of several chapters, but many others
are not. Each chapter is assigned a chapter
number enabling you to locate the chapter you
want.
Dolby Digital (“5.1”, “AC-3”)
This sound format for movie theaters is more
advanced than Dolby Pro Logic Surround. In this
format, the rear speakers output stereo sound
with an expanded frequency range and a
subwoofer channel for deep bass is
independently provided. This format is also called
“5.1” because the subwoofer channel is counted
as 0.1 channel (since it functions only when a
deep bass effect is needed). All six channels in
this format are recorded separately for superior
channel separation. Furthermore, since all the
signals are processed digitally, less signal
degradation occurs. The name “AC-3” comes
from the fact that it is the third audio coding
method to be developed by the Dolby
Laboratories Licensing Corporation.
Manufactured under license from Dolby
Laboratories. "Dolby", "AC-3", "Pro Logic" and
the Double-D symbol are trademarks of Dolby
Laboratories. Confidential Unpublished Works.
© 1992.1997 Dolby Laboratories, Inc. All rights
reserved.
Dolby Pro Logic II Surround
This is a method of decoding surround recordings
that produces five channels from two-channel
sound. Compared with the former Dolby
Surround system, Dolby Pro Logic II Surround
reproduces left-to-right panning more naturally
and localizes sounds more precisely. To take full
advantage of Dolby Pro Logic II Surround, you
should have a pair of rear speakers and a center
speaker. The rear speakers output stereo sound.
DTS
Digital audio compression technology developed
by Digital Theater Systems, Inc.This technology
conforms to 5.1-channel surround. The rear
channels are stereo and there is a discrete
subwoofer channel in this format. DTS provides
5.1 discrete channels of high quality digital
audio. Good channel separation is realized,
because all channels are recorded discretely and
processed digitally.
Manufactured under license from Digital Theater
Systems, Inc. US Pat. No. 5,451,942 and other
worldwide patents issued and pending. "DTS"
and "DTS Digital Surround" are trademarks of
Digital Theater Systems, Inc.
© 1996 Digital Theater Systems, Inc.All rights
reserved.
MPEG AUDIO
International standard coding system to
compress audio digital signals authorized by
ISO/IEC. MPEG 1 conforms to up to 2-channel
stereo, used on some DVD’s as alternate (other
language) track.
DVD
A disc that contains up to 8 hours of moving
pictures even though its diameter is the same as
a CD. The data capacity of a single-layer and
single-sided DVD, at 4.7 GB (Giga Byte), is 7
times that of a CD. Furthermore, the data
capacity of a dual-layer and single-sided DVD is
8.5 GB, a single-layer and double-sided DVD 9.4
GB, and a dual-layer and double-sided DVD 17
GB. The picture data uses the MPEG 2 format,
one of the worldwide standards of digital
compression technology. The picture data is
compressed to about 1/40 of its original size. The
DVD also uses the variable rate coding
technology that changes the data to be allocated
according to the status of the picture. The audio
data is recorded in Dolby Digital, DTS and/or
PCM, allowing you to enjoy more natural audio
presence. Furthermore, various advanced
functions such as multi-angle, multilingual, and
subtitles may be provided with the DVD.
Multi-angle function
Various angles or viewpoints of the video camera
for a scene are recorded on some DVDs.
Multilingual function
Several languages for the sound or subtitles in a
picture are recorded on some DVDs.
Parental Control
A function of some (particulary US) DVD’s to limit
playback of the disc by the age of the users. The
limitation varies from disc to disc. When it is
activated, playback is completely prohibited,
violent scenes are skipped or replaced with other
scenes and so on.
Title
The longest sections of a picture or a music piece
on a DVD; a movie, etc., for a picture piece on
video software; or an album, etc., for a music
piece on an audio software. Each title is assigned
a title number enabling you to locate the title
you want.
Track
Sections of a music piece on a CD. Each track is
assigned a track number enabling you to locate
the track you want.
PCM
Pulse code modulation, an uncompressed data
formation.
NTSC
National TV Systems Committee: a video
standard used in USA.
PAL
Phase Alternation Line: a video standard used in
many European countries.