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GLOSSARY
Bitstream
This is the digital form of multiple channel audio data
(eg., 5.1 channel) before it is decoded into its various
channels.
CINEMA DSP
Since the Dolby Surround and DTS systems were
originally designed for use in movie theaters, their effect
is best felt in a theater having many speakers and
designed for acoustic effects. Since home conditions,
such as room size, wall material, number of speakers, and
so on, can differ so widely, it’s inevitable that there are
differences in the sound heard as well. Based on a wealth
of actually measured data, YAMAHA CINEMA DSP uses
YAMAHA original sound field technology to combine
Dolby Pro Logic, Dolby Digital and DTS systems to
provide the visual and audio experience of movie theater
in the listening room of your own home.
Component video signal
With the component video signal system, the video signal
is separated into the Y signal for the luminance and the
P
B
/C
B
and P
R
/C
R
signals for the chrominance. Color can
be reproduced more faithfully with this system because
each of these signals is independent. The component
signal is also called the “color difference signal” because
the luminance signal is subtracted from the color signal.
A monitor with component input jacks is required in
order to use the component signal for output.
Decoder
A decoder restores the coded signals on DVDs to normal.
This is called decoding.
Dolby Digital
This is a method of coding digital signals developed by
Dolby Laboratories. Apart from stereo (2-channel) audio,
these signals can also be 5.1-channel audio. A large
amount of audio information can be recorded on one disc
using this method.
Dolby Pro Logic
A surround system where a 4-channel audio track is
recorded as 2 channels and then is restored to 4 channels
for play. The surround channel is monaural and can
reproduce up to 7 kHz.
Dolby Pro Logic II
Dolby Pro Logic II is an improved technique used to
decode vast numbers of existing Dolby Surround
software. This new technology enables a discrete 5-
channel playback with 2 front channels, 1 center channel,
and 2 rear channels (instead of only 1 rear channel for
conventional Pro Logic technology). A music mode is
also available for 2-channel sources in addition to the
movie mode.
DTS (Digital Theater Systems)
This surround system is used in many movie theaters
around the world. There is good separation between the
channels, so realistic sound effects are possible.
Dynamic range
Dynamic range is the difference between the lowest level
of sound that can be heard above the noise of the
equipment and the highest level of sound before distortion
occurs.
Film and video
DVDs are recorded using either film or video. Film is
recorded at 24 frames per second, the rate movies are
filmed at, although some recent progressive material is
recorded at 30 frames per second.
Video is recorded at 30 frames per second.
Frame still and field still
A still is shown when you pause a moving picture. A
frame still is made up of two alternating fields, so the
picture may appear blurred, but overall quality is high.
A field still is not blurred, but it has only half the
information of a frame still so picture quality is lower.
Frames are the still pictures that go together to make a
moving picture.
There are about 30 frames shown each second.
One frame is made up of two fields. A regular television
shows these fields one after the other to create frames.
Group
A DVD audio disc is divided into large sections called
“groups” and smaller sections called “tracks”. The
numbers allocated to these sections are called “group
numbers” and “track numbers”.