Kompernass KH 6504 Glossary / Key Word Index, What are DVDs, VCDs and S-VCDs?, Dolby Surround

17. Glossary / Key Word Index

17.1What are DVDs, VCDs and S-VCDs?

DVDs

DVD is the short form for "Digital Versatile Disc". DVDs are a storage medium for audio and video data; they are available in 8 cm and 12 cm (Diameter) formats. Because of the much higher storage capa- city as compared to CD-Rs/CD-RWs DVDs can pro- vide 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 (Play- back Control) functions are available. In addi- tion still images can be played back in a hig- her resolution.

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 operated.

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 DVD/VCD/ S-VCD or its title is divided into chapters, numbers are assigned to you, through the input of which the chapter can be selected direct.

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 informa- tion for further channels. With a Dolby Surround de- coder the signals are again converted into sound and/or music and are fed to two additional loud- speakers, which are to be situated behind the liste- ning area.

Dolby Prologic

In comparison to Dolby Surround sound format, with Dolby Prologic an additional channel in the stereo 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 sub- woofer 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 locali- zed exactely by the human ear

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