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DVD video players are exclusively for reproduction, including music CDs.
DVD video discs with the following marks and music CDs are capable of being reproduced.

Mark (logo)

Content

Size of Disc

Maximum

One side of the disc

12cm

for  approx. 4 hours

Two side of the disc

DVD Video Disc

Audio + Visual

for  approx. 8 hours

(animation)

One side of the disc

8cm

for  approx. 80 minutes

Two side of the disc

for approx. 160 minutes

12cm

74 min.

Music CD

Audio

8cm

20 min.

(CD Single)

Video CD

Audio + Visual

12cm

74 min.

No discs other than those listed above can be reproduced.
This player matches the NTSC TV system.  Discs shown with other TV systems (PAL, SECAM)
cannot be used.

Local codes are established in different countries around the world, including  Japan, U.S.A./
Canada, Asia and Europe.
Some DVD video disc have established local codes.  This is the result of software production
sales tactics.  They make DVD video discs, especially for new movies and songs, and industrial
use discs, that are to be reproduced only in official sales areas.  Therefore, it is possible to see
a message such that says “this disc cannot be reproduced due to the differences in local codes”
when one buys a DVD video disc outside of his/her country and try to play it or industrial use
videos at home.

To protect copyright, it is prohibited to copy, broadcast, publicly show, broadcast over a cable
system, show at public lectures, or rent (whether or not charging for it) a disc.  On DVD video
players, copied picture won’t project as clear an image if it has been copied from another video
deck.

In converting music and data images into a unified file format, the border between TV and audio
or computer is removed.  As a result, DVD discs have many possible usages, including personal
computer reproduction of DVD software and the playing of traditional audio CDs on the DVD
player due to the compatibility of the hardware.

DVD video discs are divided into big ends called “titles” and small ends called “chapters”.  Music
CDs are divided into “tracks”.

Audio CD

CD-ROM

DVD-ROM
DVD-Rewritable

~

~

~

~

~

A section of the DVD content divided into large parts.  They correspond to the “story”
part of a collection of short stories.

Chapter : Sections of the Title’s contents are divided into smaller parts, such as scenes and tunes.

It corresponds to the “chapter” of a book.

A section made up of one song in a music CD.

Each title, chapter and track are numbered in order.  These numbers are also called “Title
Numbers”, “Chapter Numbers” and “Track Numbers”.
Some discs may not have each number recorded.

Even though the recording capacity of DVD discs is 7 times more than a CD, if a TV image on
NTSC is digitally transferred and recorded, even the DVD disc can record only 4 minutes.
Research of the technology to record more information in a limited recording capacity (data
compression) started in the 1960s.  The progression has went from JPEG, MPEG1 to MPEG2.
MPEG1, which was adopted for Video CDs (karaoke, etc.), can record a maximum of 74 minutes
of moving images by compressing the data to 1/100, but the picture quality is inferior to LDs.
MPEG2 offers a high quality picture by compressing the information to approximately 1/40,
adding new technology to MPEG1 and increasing the compression rate.  Diversified improvements
include changes in the data transfer rate (variable), frame rate (double) and predicting primenumbers
on corresponding pictures (double) between frames and field DCT.

Picture compression system

MPEG2(DVD)

MPEG1(Video CD)

 (adopted equipment)

Main picture degree

720 x 480

720 x 480

of resolution

picture pixels

picture pixels

Frame Rate

Data transfer speed

1~10Mbit/sec. (variable)

1.15Mbit/sec. (fix)

Average compression rate

Approximately 1/40

 Approximately 1/100

Picture quality

More than LD

About the same as VHS

*MPEG = Moving Picture Experts Group
This is the title of the compression technology working group, which is a part of the ISO/IEC
Joint Technology Committee, which in turn is part of the substructure of ISO and IEC.

MPEG2 commands technological skill related to compression, which is comprised of about 20
items.
It increases the amount of information not only when complicated or fast moving pictures are
running (about 10Mbps),
but when slow or almost still pictures are running, it dramatically decreases the amount of
information (about 1Mbps).
Overall, it attains a high quality picture with a data transfer rate of average 3.5Mbps.

When you see a TV picture, you think of it as a sequentially moving picture, thanks to the
afterimage effect that “fools” our eyes.  But in reality, what you are watching is a series of still
pictures that move sequentially and change at a steady rate.
Therefore, it recognizes monotonous and complicated parts on still picture frames (spatial
information).  Than, it decreases the amount of data (higher compression) for monotonous parts
and increases the amount of data (lower compression) for complicated parts.
Also, since moving pictures are a succession of still pictures, the system compares each picture
to the ones before it and memorizes upcoming ones in order to detect how much current picture
moved.  It then records only the moving part or parts (time information) as data.  Reproduction
is done in reverse (encode) in order to replace data (decode).

The picture is divided into small micro blocks.  Each block is again divided into smaller
blocks. (See the drawing below.)
Then, the complication of each picture is detected on each block, converting it into DCT
= frequency, in order to sort monotonous parts (unnecessary information) from compli-
cated parts (necessary information) by numeric value.

The data converted into numeric value (frequency) by DCT will be more compressed in its
flat parts, where more information stays, by dividing it by a common value to make it
quantitated.