17. Glossary / Key Word Index
17.1 What are DVDs, VCDs and
S-VCDs?
DVDs
DVD is the abbreviation for "Digital Versatile Disc".
DVDs are a storage medium for audio and video
data; they are available in 8 cm and 12 cm (Dia-
meter) formats. Because of the much higher storage
capacity as compared to CD-Rs/CD-RWs DVDs can
provide a playback duration of up to eight hours for
the audio and video data stored on them.
VCDs/S-VCDs
"Video CD" (VCD) and "Super Video CD" (S-VCD)
are designations for two processes of compressed
storage, thus space saving, of films on CDs. VCDs
and S-VCDs are available in 8 cm and 12 cm (Dia-
meter) formats. Their storage capacity is a great
deal lower than that of DVDs. For this reason they
only offer a playback duration, for the saved audio
and video data on them, of 20 minutes (8 cm for-
mat) and/or 74 minutes (12 cm format).
VCDs are available in two versions:
• With version 1.1 VCDs/S-VCDs only audio and
video data can be played back.
• With version 2.0 VCDs/S-VCDs, PBC (Playback
Control) functions are available. In addition still
images can be played back in a higher resolu-
tion.
Playback Control (PBC)
Version 2.0 VCDs/S-VCDs have Playback Control
(in short "PBC") at their disposal. Then on the VCD/
S-VCD a main menu is available, by which various
functions of the VCD/S-VCD are allowed to be ope-
rated.
17.2 What are Title and Chapter?
Title is the name given to the largest units of image
and sound units on DVDs; on many DVDs the
(Main) film has the title number 01. For bonus mate-
rial (i.e. Film trailer, background information etc.),
that is available on many DVDs, other possible title
numbers can be used.
Chapter is the name given to the next smaller image
and sound units beneath title. If the title or titles on
a DVD/VCD/S-VCD are subdivided into chapters,
they are assigned numbers that can be entered to
select the chapters directly.
Bear in mind that not on all DVDs ...
• are the DVD or the title divided into (numbered)
chapters
• Chapters are also designated as "Scenes"
(i.e. in the main menu of DVDs)
17.3 Dolby Surround
Dolby Surround is an analogue sound format, by
which the two channels of a stereo sound signal
are used in order to accommodate room sound
information for further channels. With a Dolby Sur-
round decoder the signals are again converted into
sound and/or music and are fed to two additional
loudspeakers, which are to be situated behind the
listening area.
Dolby Prologic
In comparison to Dolby Surround sound format,
with Dolby Prologic an additional channel in the ste-
reo signal is used; this is the so called "Centre"
channel. The corresponding centre loudspeaker is
to be situated in the middle between the stereo
loudspeakers. The deepest sounds are fed to a bass
loudspeaker, the so called "Subwoofer". The subwo-
ofer can be placed in any desired location in the
room; the logic for this is that the bass sounds that
the subwoofer puts out can scarcely be localized
exactely by the human ear
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