Yamaha DVD-S1200 - Manual (Page 29)

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Reference
Do not use irregularly shaped discs, such as heart-shaped.
(These can damage the unit.)
º
How to hold a disc
Do not touch the recorded surface.
P: Predictive coded picture (P-picture)
This picture is calculated based on past I or P-pictures.
B: Bidirectionally-predictive coded picture (B-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)
PCM is the usual digital method used for music CDs. DVDs have a
greater volume so they use linear PCM, which has a higher sampling
rate. Compressed PCM signals are called packed PCM (PPCM).
Optical digital audio cable
Electronic signals are converted to optical signals for output to the
amplifier. This reduces noise caused by electronic interference.
Pan&Scan/Letterbox
In general, DVD-Video are produced with the intention that they be
viewed on a widescreen television with an aspect ratio of 16:9. This
means you can view most material with the intended aspect ratio on a
widescreen television.
Material with this ratio will not fit onto a standard television with an
aspect ratio of 4:3. Two styles of picture, “Pan&Scan” and “Letter-
box”, deal with this problem.
Pan&Scan:
the sides are cut off so the picture fills the screen.
Letterbox: black bands appear at the top and bottom of the
picture so the picture itself appears in an aspect ratio
of 16:9.
Playback control (PBC)
If a Video CD has “playback control” written on it or its jacket, it
means that particular scenes or information can be selected for view-
ing interactively with the television using the menu screen. This unit
can play Video CDs with playback control.
Using menus to control play of a Video CD is called “menu play” in
these operating instructions.
Sampling rate
This is the number of samples of sound taken per second during con-
version to a digital signal. Sampling frequency is expressed in kilo-
hertz (kHz). A high sampling frequency results in a sound close to the
original when played back.
Title/Chapter
DVD-Video are divided up into large sections, titles, and smaller sec-
tions, chapters. The numbers allocated to these sections are called
title numbers and chapter numbers.
Track
This is the smallest division on DVD-Audio, CD, and Video CD, and
usually equates to a single song.
Bitstream
This is the digital form of multiple channel audio data (e.g., 5.1 chan-
nel) before it is decoded into its various channels.
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 Labora-
tories. Apart from stereo (2-channel) audio, these signals can also be
5.1-channel audio. A large amount of audio information can be re-
corded 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.
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
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 pic-
ture. 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.
I/P/B
MPEG, the video compression standard adopted for use with DVD-
Video, codes frames using these 3 picture types.
I: Intra coded picture (I-picture)
This is the standard picture and is a complete picture in itself.
This means it has the best picture quality and is the best to use
when adjusting the picture.
Glossary
Disc handling
º
If the disc is brought from a cold to a warm
environment, moisture may form on the disc
Wipe with a soft, dry, lint-free cloth before using the disc.
º
Handling precautions
³ Do not write on the label side with a ball-point pen or other writing
instrument.
³ Do not use record cleaning sprays, benzine, thinner, static electric-
ity prevention liquids or any other solvent.
³ Do not attach labels or stickers to discs. (Do not use discs with ex-
posed adhesive from tape or left over peeled-off stickers.)
³ Do not use scratch-proof protectors or covers.
³ Do not use discs printed with label printers available on the market.
º Do not place or store discs in the following
places
³ Locations exposed to direct sunlight
³ Humid or dusty locations
³ Locations directly exposed to a heat vent or heating appliance
º
If the surface is dirty
Wipe it with a damp cloth and then wipe dry.
Do not wipe with a circular motion; wipe straight outward from the
center.