Glossary

Bitstream

This is the digital form of multiple channel audio data (e.g., 5.1 channel) before it is decoded into its various channels.

Chapter

This is the smallest division on DVDs and is roughly equivalent to a track.

Dolby Digital

This is a method of coding digital signals developed by Dolby Laboratories. Apart from stereo (2-channel) audio, these sig- nals can also be 5.1-channel audio. A large amount of audio information can be recorded on the 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)

Reference

This is a method of coding digital signals

developed by Digital Theater Systems.

 

 

The signals are compressed at a low ratio

Your

to maintain sound quality.

Dynamic range

 

For

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 dis-

 

tortion occurs.

 

Field

 

One frame is made up of 2 fields.

 

A regular television shows these fields

 

one after the other to create frames.

 

Frame

 

Frames are the still pictures that go to-

 

gether to make a moving picture.

 

There are about 30 frames shown each

 

second.

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RQT6077

Frame still and field still

A still is shown when you pause a moving picture.

A frame still is made up of 2 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 pic- ture quality is lower.

I/P/B

MPEG 2, the video compression standard adopted for use with DVDs, 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.

P:Predictive coded picture (P-picture) This picture is calculated based on past I or P-pictures.

B:Bidirectionally-predictive coded pic- ture (B-picture)

This picture is calculated by compar- ing past and future I and P-pictures so it has the lowest volume of infor- mation.

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 high- er sampling rate.

Playback control (PBC)

This method of controlling disc play is included on version 2.0 Video CDs. You are able to interact with the disc through menus.

Title

This is the largest division on DVDs.

Track

This is the smallest division on Video CDs and CDs and usually equates to a single song.

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Panasonic DVD-LV57 operating instructions Glossary, Your, For