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The audio data is recorded in Dolby Digital as well as in PCM,
allowing you to enjoy more real audio presence.
Furthermore, various advanced functions such as the multi-angle,
multilingual, and Parental Control functions are 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 the DVD to limit playback of the disc by the age of the
users according to the limitation level in each country. 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.
Playback Control (PBC)
Signals encoded on Video CDs (Version 2.0) to control playback.
By using menu screens recorded on Video CDs with PBC functions,
you can enjoy playing simple interactive programs, programs with
search functions, 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 picture or a music piece on a CD or Video CD. Each
track is assigned a track number enabling you to locate the track
you want.
Video CD
A compact disc that contains moving pictures.
The picture data uses the MPEG 1 format, one of the worldwide
standards of digital compression technology.
The picture data is compressed to about 1/140 of its original size.
Consequently, a 12 cm Video Disc can contain up to 74 minutes of
moving pictures.
Video CDs also contain compact audio data. Sounds outside the
range of human hearing are compressed while the sounds we can
hear are not compressed. Video CDs can hold 6 times the audio
information of conventional audio CDs.
There are 2 versions of Video CDs.
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Version 1.1: You can play only moving pictures and sounds.
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Version 2.0: You can play high-resolution still pictures and enjoy
PBC functions.
This system conforms to both versions.
Glossary
Bit rate
Value indicating the amount of video data compressed in a DVD per
second. The unit is Mbps (mega bit per second). 1 Mbps indicates
that the data per second is 1,000,000 bits. The higher the bit rate is,
the larger the amount of data. However, this does not always mean
that you can get higher quality pictures.
Chapter
Sections of a picture or a music piece on a DVD that are smaller
than titles. A title is composed of several chapters. Each chapter is
assigned a chapter number enabling you to locate the chapter you
want.
Dolby Digital
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 to realize superior
channel separation. Furtheremore, 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.
Dolby Pro Logic Surround
As one method of decoding Dolby Surround, Dolby Pro Logic
Surround produces four channels from two-channel sound.
Compared with the former Dolby Surround system, Dolby Pro Logic
Surround reproduces left-to-right panning more naturally and
localizes sounds more precisely. To take full advantage of Dolby Pro
Logic Surround, you should have one pair of rear speakers and a
center speaker. The rear speakers output monaural sound.
DTS
Digital audio compression technology that the Digital Theater
Systems, Inc. developed. This technology conforms to 5.1-channel
surround. The rear channel is stereo and there is discrete
subwoofer channel in this format. DTS provides the same 5.1
discrete channels of high quality digital audio. The good channel
separation is realized because the all channel data is recorded
discretely and digitally processed.
MPEG AUDIO
International standard coding system to compress audio digital
signals authorized by ISO/IEC. MPEG 1 conforms to up to 2-channel
stereo. MPEG 2 used on DVDs conforms to up to 7.1-channel
surround.
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.