JP2979739B2 - Video signal distribution system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal distribution system for distributing compressed image digital data in a short time.

[0002]

2. Description of the Related Art Conventionally, cable broadcasting such as television broadcasting and CATV has been known as a system for transmitting video signal information. However, these are all transmitted in real time, that is, it takes one hour to transmit a one-hour program.

[0003] Also, recording and supplying video signal information to video tapes or optical disks as package media has been widely performed. However, this system does not record desired information on the spot, but uses these packages. A large space for storing was needed.

On the other hand, optical transmission using an optical fiber as a transmission path is in full swing. This transmission capacity is large and can transmit an information amount of, for example, about 150 Mbps. If this transmission is used, it becomes possible to transmit information of about 120 Mbps of digital data of the NTSC signal in real time.

[0005]

[Problems to be solved by the invention] Transmit video signal information
To transmit via package or in real time
Is used, but the desired video signal can be
There is no system to obtain information.

[0006]

According to the present invention, there is provided a video signal distribution system according to the present invention.
A stem from the first storage medium of the first player;
Digital video information recorded on media can be played back in real time
At a first high transfer rate higher than the required transfer rate
Digital video information read from each head is
Transmission at a second higher transfer rate higher than the transfer rate
However, in the second recording machine, each head is substantially the first high transfer
Recording said information in a second storage medium at a rate,
Digital video information required for real-time playback
Reproduction at a low transfer rate substantially equal to the transfer rate
And the first player and the second recorder are
Recording or reproducing disk having m (m is plural) heads
Disc device, wherein the third player is at least one
Characterized by being a playback disk device having a head.
Is what you do.

[0007]

According to this, when transmitting the desired video signal information, it is transmitted and recorded in a time much shorter than the real time,
After that, it becomes possible to reproduce in real time with a reproduction-only machine.

[0008]

【Example】 One embodiment of the video signal distribution system of the present invention
This will be described in detail with reference to FIG.

The system according to the present invention comprises a high-speed reproduction system 1,
It comprises a high-speed transmission system 2, a high-speed recording system 3, and a low-speed reproduction system 4.

The high-speed reproduction system 1 comprises a high-speed reproduction device 5, an optical disk 6, a plurality of optical heads 7, 8, and a reproduction signal processing system 9, and reproduces image data at high speed.

The high-speed transmission system 2 includes an optical transmission processing unit 10, an optical transmission unit 11, and an optical reception processing unit 12,
It transmits information at a high speed, for example, at a rate of 150 Mbps.

The high-speed recording system 3 includes a recording signal processing system 13, a high-speed recording device 17, an optical disk 16, a plurality of optical heads 14,
15 for recording image data at high speed.

The low-speed reproduction system 4 comprises a low-speed reproduction device 19, an optical disk 18, an optical head 20, and a reproduction signal processing system 21, and reproduces image data at low speed in real time.

Here, as the image data, band-compressed digital image data, for example, an NTSC signal compressed to 5 Mbps is considered.

The high-speed reproduction system 1 converts an NTSC signal compressed to 5 Mbps into a high transfer rate, for example, 150 Mbps.
Read with s. That is, reading is performed at a speed 30 times faster than real time.

Similarly, the high-speed transmission system 2 and the high-speed recording system 3 process at a high transfer rate of 150 Mbps, which is 30 times the speed of real time, and record image information on the disk 16.

The recorded disk 16 and the disk 18
Are the same disk. The disc 18 is reproduced in real time by a reproduction-only device 19 and the reproduction signal processing system 21
Send bps information. Thereby, the reproduction signal processing system 21
Then, the decoded NTSC signal can be obtained at the terminal 22 by decoding the image.

That is, a 5 Mbps signal is converted to a 150 Mbps signal.
Since the processing is performed in ps, the transmission processing time is reduced to 1/30. That is, if the image information is one hour,
The transmission is completed in two minutes.

Here, the high-speed reproducing device 5 and the high-speed recording device 17
It is desirable to have a plurality of heads to realize a high transfer rate. Although the embodiment shows an example having two heads, this eliminates the need to increase the relative speed between the optical disk and the optical head by 30 times.
= 15, that is, approximately 15 times.

The rotation of the disk is controlled at a constant rotational speed (CAV) in a high-speed reproducing / recording apparatus having a plurality of heads.
Is desirable in terms of control. However, it is desirable from the viewpoint of recording density that the discs recorded thereby, in the embodiment, the discs 16 and 18 have a format in which the disc is reproduced at a constant linear velocity (CLV) control when reproduced at a low transfer rate. . This can be realized by rotating a disk recorded in a format having a constant linear velocity at a high speed at a constant rotation speed within a range where the maximum transfer rate does not exceed the capacity of the transmission system.

Here, the number of optical heads of the recording / reproducing disk of the high transfer rate is not limited to two, but may be three or one.

The high transfer rate recorder 17 and the low transfer rate reproducer 19 may be the same and may be used in common.

The band compressed image data is 5 Mbps.
The NTSC signal is not limited to about 1 Mbps, about 20 Mbps, or a high-definition image (H
DTV) data or audio signal data.

[0024]

As described above, the video signal distribution system according to the present invention is
According to the system, when transmitting the desired video signal information,
It is possible to provide a video signal distribution system capable of transmitting and recording in a time much shorter than the real time and thereafter reproducing the data in a real time by a reproducing device .

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High-speed reproduction system 2 High-speed transmission system 3 High-speed recording system 4 Low-speed reproduction system 5 High-speed reproduction machine 6, 16, 18 Optical disk 7, 8, 14, 15, 20 Optical head 9 Reproduction signal processing system 10 Optical transmission processing unit 11 Optical transmission Unit 12 Optical reception processing unit 13 Recording signal processing system 17 High-speed recording device 19 Low-speed reproduction device 21 Reproduction signal processing system

Claims (5)

(57) [Claims] 1. A first storage medium of a first player,
Digital video information recorded on a recording medium is reproduced in real time.
First high transfer rate higher than the transfer rate required for raw
Digital video information read from each head at
At a second higher transfer rate higher than the higher transfer rate
Transmitting, in the second recorder, each head is substantially at the first height.
The information is recorded on a second storage medium at a transfer rate, and the digital video information is stored in the second storage medium for real-time reproduction.
Third transfer at a low transfer rate approximately equal to the required transfer rate
Reproduced by the reproducing apparatus, the first player, and the second recording unit is m number (m is double
A recording or reproducing disk device having the head of
The third player has at least one head
Video signal distribution system, characterized in that it is a playback disk device . 2. The method according to claim 1, wherein the first storage medium of the first playback device stores the
Digital video information recorded on a recording medium is reproduced in real time.
Read at a higher transfer rate than the transfer rate required for raw
The digital video information found is converted to approximately the high transfer rate
Transmitted to the second storage medium substantially at the high transfer rate.
The information is recorded by a second recording device in the
The medium requires the digital video information for real-time playback
At the third player at a low transfer rate that is almost equal to the transfer rate
Reproduce and make the ratio between the high transfer rate and the low transfer rate L times
And the relative speed between the head of the third player and the storage medium
Is n in the first player and the second recorder
(N is a natural number) of the average relative speed between the head and the storage medium
A video signal distribution system having a relative speed satisfying substantially n / L. 3. The method according to claim 1, wherein the first storage medium of the first playback device stores the
Digital video information recorded on a recording medium is reproduced in real time.
Read at a higher transfer rate than the transfer rate required for raw
The digital video information found is converted to approximately the high transfer rate
Transmitted to the second storage medium substantially at the high transfer rate.
The information is recorded by a second recording device in the
The medium requires the digital video information for real-time playback
At the third player at a low transfer rate that is almost equal to the transfer rate
Reproduce and make the ratio between the high transfer rate and the low transfer rate L times
And average transfer between the head of the third player and the storage medium
The rate is determined by the first player and the second recorder.
Average transfer between n (n is a natural number) heads and storage media
It is an average transfer rate that satisfies approximately n / L of the rate.
Characteristic video signal distribution system. 4. The first reproducing device and the second recording device are controlled at a constant rotation speed, and the third reproducing device is controlled at a constant linear speed.
4. The video signal distribution system according to claim 1 , wherein the video signal is distributed. 5. The apparatus according to claim 1, wherein the second recorder and the third player are the same device.
4. The method according to claim 1, 2 or 3, wherein
Video signal distribution system.