Digital recording of both image and sound, Audio recording, How mpeg-2 video compression works – Sony RDR-GX7 User Manual

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video recording

High quality digital recording of
audio and video

MPEG-2

audio recording

Dolby Digital
Linear PCM
MPEG audio

The primary digital recording formats

used in writable DVD

Just like DVD-Video, writable DVD digitally

records video using the MPEG-2 format,

and digitally records audio using Dolby

Digital and other formats. This assures

extremely high quality video and audio

recording, while also ensuring playback

compatibility on conventional DVD players.

Digital recording of both image and sound.

Common features of
writable DVD

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How MPEG-2 video compression works

MPEG-2 is a highly efficient and effective technology for the compression of video signals at

variable rates. The areas of movement in each scene are determined, and for areas where

there is no change, the volume of data representing those areas can be greatly reduced.

Fixed bit rate compression & variable bit rate compression

Writable DVD can be recorded at not only fixed transmission rates, but also at variable

transmission rates which enable high image quality recording of complex video images at the

same average transmission rate.

Compression in field unites.
(The image is digitalized in
field units and compressed.)

Compression on time axis.
(The imaage is compressed by
determining the volume of movement.)

Compressed to

1/40th, on average.

Data volume

Time axis

Impossible

Average
transmission rate

Waste

Average
transmission rate

Variable
compression bit rate

Fixed
compression bit rate

The rate of compression is

varied depending upon data

volume to increase efficiency.

When the transmission rate is fixed,

signal transmission is inefficient,

and portions which cannot be transmitted

result in deterioration of playback quality.

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