30
GLOSSARY
Glossary
Bit rate
Value indicating the amount of video data com-
pressed 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 com-
posed 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 sub-
woofer 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 separa-
tion. 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 Confidential Unpublished Works.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 stereo or 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 sub-
woofer 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 com-
press 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 acti-
vated, 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.
