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RQT7991
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Glossary
Decoder
A decoder restores the coded audio signals on DVD’s 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 multi-channel audio. A large amount of audio information can
be recorded on one disc using this method.
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.
Frame still and field still
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.
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.
I/P/B
MPEG 2, the video compression standard adopted for use with
DVD-Video, codes frames using these 3 picture types.
I:
Intra coded picture
This picture has the best quality and is the best to use when
adjusting the picture.
P:
Predictive coded picture
This picture is calculated based on past I or P-pictures.
B:
Bidirectionally-predictive coded picture
This picture is calculated by comparing past and future I and
P-pictures so it has the lowest volume of information.
Linear PCM (pulse code modulation)
These are uncompressed digital signals, similar to those found on
CDs.
Playback control (PBC)
If a Video CD has playback control, you can select scenes and
information with menus.
Sampling frequency
Sampling is the process of converting the heights of sound wave
(analog signal) samples taken at set periods into digits (digital
encoding). Sampling frequency is the number of samples taken per
second, so larger numbers mean more faithful reproduction of the
original sound.
Clean this unit with a soft, dry cloth.
≥
Never use alcohol, paint thinner or benzine to clean this unit.
≥
Before using chemically treated cloth, carefully read the
instructions that came with the cloth.
Do not use commercially available lens cleaners as they may
cause malfunction.
(Cleaning of the lens is generally not necessary
although this depends on the operating environment.)
Maintenance
Before moving the unit, ensure the disc tray is empty.
Failure to do so will risk severely damaging the disc and the
unit.
HT880W_En.book Page 30 Thursday, January 20, 2005 12:22 AM
