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Glossary
Aspect ratio
The width of a TV screen relative to its height. Conventional
TVs are 4:3 (in other words, the screen is almost
square);widescreen models are 16:9 (the screen is almost
twice as wide as it is high).
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.
Bonus Group
An extra group on some DVD-Audio discs that requires a key
number to access.
Browsable pictures
A feature of some DVD-Audio discs in which the user can
browse still pictures recorded on the disc as the audio is
played. See also Slideshow.
Chapter
Sections of a picture or a music piece on a DVD-Video 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.
Digital audio
An indirect representation of sound by numbers. During
recording, the sound is measured at discrete intervals (44,100
times a second for CD audio) by an analog-to-digital converter,
generating a stream of numbers. On playback, a digital-to-
analog converter generates an analog signal based on these
numbers.
Dolby Digital
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. 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.
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.
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 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.
Dynamic range
The difference between the quietest and loudest sounds
possible in an audio signal (without distorting or getting lost in
noise). Dolby Digital and DTS soundtracks are capable of a
very wide dynamic range, delivering dramatic cinema-like
effects.
Group
A collection of tracks on a DVD-Audio disc. Equivalent to "title"
of a DVD-Video disc.
MP3
MP3 (MPEG1 audio layer 3) is a compressed audio file format.
Files are recognized by their file extension ".mp3".
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.
This player can convert MPEG audio to PCM format.
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