JPH08317338A - Data transmitter - Google Patents

Abstract

PURPOSE: To provide a data transmitter with which program data can be immediately transmitted corresponding to the request of a receiver or a rapid program change. CONSTITUTION: At a data transmitter 1, plural kinds of video data are respectively divided into data at every prescribed time by a data preparing part 10, compressed-encoded for each piece of divided data and continuously arranged for each piece of data to be simultaneously transmitted, and video data for multi-channel transmission are prepared. The prepared video data for multi-channel transmission are recorded in a data storage part 20 as a data storage means which can automatically exchange a tape recording medium and enables high speed reproduction. The video data for multi-channel transmission recorded in the data storage part 20 are reproduced at high speed corresponding to the request, transferred to a recording means, which enables continuous and repeated reproduction, at a data transmitting part 30, separated for each piece of plural kinds of video data and simultaneously transmitted to plural channels.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmitting apparatus suitable for use in a video-on-demand apparatus capable of delivering video data in response to a request generated at an arbitrary time.

[0002]

2. Description of the Related Art A video-on-demand (VOD) system and a near-video-on-demand (NVOD) system for providing a program in response to a request from a receiver are being realized. In particular, the NVOD system is a VOD. It is attracting attention because the equipment is simpler than the system.
The NVOD system is a channel in which a program such as a movie is sent to a plurality of channels while being shifted for a certain period of time, and when a receiver requests viewing of the program, the program is sent from the beginning at the time closest to the request. Is selected so that the request of the recipient can be met.

In the NVOD system, the basic method of simultaneously transmitting AV data (hereinafter also referred to as video data) including either or both of video data and audio data to a large number of channels is as follows. This is a method in which a reproducing apparatus corresponding to each channel is provided, and each independently reproduces video data recorded on a VTR tape or the like and sends the data to a plurality of channels.

Further, in recent years, the recording capacity of a randomly accessible recording medium such as a hard magnetic disk device or a magneto-optical (MO) disk device has greatly increased, and access has become faster, and AV data compression has been achieved. Due to the progress of technology and the like, an NVOD system using such a randomly accessible recording medium has also been constructed. In the system, the recording device reads out the recorded video data simultaneously in a time division manner as a plurality of data streams, so that one recording device can send the data to a plurality of channels. In addition, in this case, in order to read the data as fast as possible, multi-channel transmission data in which the data are arranged in order so that a plurality of data streams can be generated by sequentially reading the data is created in advance. Then, at the time of data transmission, such multi-channel transmission data that has been created and stored in advance is transferred to a recording device of the data transmission unit that can be continuously and repeatedly reproduced, and the data is transmitted. I have to.

[0005]

However, in such a data transmission apparatus used in, for example, an NVOD system, program data for multi-channel transmission, which has been created and stored in advance, can be efficiently used for actual data transmission. There was a problem that I could not do it.

Specifically, for example, when there is a request from the receiver or a sudden change in the provided program, the program data for multi-channel transmission stored in the hard magnetic disk device or MO disk device is converted into data. When the data is transferred to the sending recording section of the sending section, there is a problem that the transfer takes a long time and it is impossible to immediately respond to the request of the receiver or a sudden program change. Further, when a removable recording medium such as an MO disk is used for storage, a method is adopted in which the transfer of data is unnecessary by directly setting the recording medium in the reproducing device of the data transmission unit. There are cases. However, in such a method, the operator has to carry the recording medium by himself and set it in the reproducing device of the data sending unit, and therefore the operator has to perform a troublesome work and the data is not recorded. There is a problem that a predetermined work time is required as in the case of the transfer.

Therefore, an object of the present invention is to set up program data for multi-channel transmission, which has been created and stored in advance, in a state in which it can be transmitted at high speed.
Accordingly, it is an object of the present invention to provide a data transmission device capable of immediately transmitting program data in response to a request from a receiver or an abrupt program change.

[0008]

Since program data for multi-channel transmission need only be accessed sequentially, it is possible to store data on a tape recording medium as accumulating means for accumulating program data for multi-channel transmission created in advance. Is a recording means for recording a plurality of tape recording media, and recording / reproducing can be performed by automatically changing the recording medium. Therefore, a data storage device having a large recording capacity and capable of high-speed sequential reproduction is used. .

Therefore, the data transmission device of the present invention is
Encoding means for dividing a plurality of types of video data into data for each predetermined reproduction time, and compression-encoding each divided data, and a plurality of units for dividing each of the predetermined reproduction times and each compression-encoded. Sending data creation means for creating multi-channel sending video data by making consecutive kinds of video data for each data sent simultaneously and further arranging the continuous data in order of sending time; The recorded video data for multi-channel transmission is recorded and stored in the continuous storage area of the tape recording medium, the tape recording medium can be automatically changed, and the recorded data can be continuously reproduced at high speed. Means and the multichannel transmission video data continuously reproduced at high speed by the data accumulating means are recorded as transmission data and are repeated at least continuously. Reproducible recording means, and the multichannel transmission video data recorded in the recording means is continuously and repeatedly reproduced, and the continuously recorded plural kinds of video data are simultaneously transmitted. Of video data are sequentially separated for each video data, and a data sending means for sending the separated plural types of video data in parallel to a plurality of channels.

Specifically, the data accumulating means forms four reproducing heads, two reproducing heads provided in close proximity to each other at opposite positions of the drum, and an angle of about 60 ° with the reproducing heads. A rotary drum having four advanced reproducing heads, which are respectively provided in close proximity to each other at two opposite positions, and for reproducing the tape recording medium by the rotary drum, for transmitting the accumulated multi-channels. Play video data continuously and at high speed.

[0011]

In the data transmitting apparatus of the present invention, a plurality of types of video data to be transmitted at the same time are divided by the encoding means into data for each predetermined reproduction time, and a compression code is applied to each of the divided data. Turn into. Next, the plurality of types of compression-encoded video data are successively arranged in the sending data creating means for each data sent at the same time, and the continuous data are arranged in order of sending time. Then, the video data for multi-channel transmission is created. The produced video data for multi-channel transmission is recorded and accumulated in the continuous storage area of the data accumulating means which can automatically change the tape recording medium and can be reproduced at high speed.

The multi-channel transmission video data recorded in the data storage means is reproduced at high speed in response to a request and transferred as transmission data to at least continuously reproducible recording means. The multi-channel transmission video data recorded in the recording means is separated into a plurality of types of video data by the video data separation means, and the plurality of types of separated video data are separated into a plurality of channels in the data transmission means. Are sent simultaneously to.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a data transmission device of the present invention is shown in FIGS.
This will be described with reference to FIG. The data transmission apparatus of the present embodiment executes near video on demand in which a predetermined video program planned in advance is receivably delivered from the beginning of the video program at the time requested by the receiver, and A data transmission device capable of performing video-on-demand for transmitting an unplanned program in response to a request from a receiver. FIG. 1 is a block diagram showing the configuration of a data transmission device according to an embodiment of the present invention. The data transmission device 1 includes a data creation unit 10, a data storage unit 20, and a data transmission unit 30.

The configuration of each part of the data transmission device 1 will be described. First, the configuration of the data creation unit 10 will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the data creation unit 10, and the data creation unit 10 includes the input unit 1
1, encoding unit 12, FIFO unit 13, data selection unit 14
And a control unit 15.

The input section 11 is input to the data creating section 10.
Encoded program data into a signal of a predetermined format and encoded
Means for outputting to the unit 12, each of n independent input units
11 _-1~ 11_-nIt is composed of In this embodiment,
The input section 11 is composed of n VTR tape reproducing devices.
Be done. That is, the data transmission device 1 of the present embodiment is
Using the VTR tape of
The reproduced program data of is used as material data for early delivery.

The encoder 12 is means for compressing and encoding the program data input from the input unit 11 and outputting it to the FIFO unit 13, which corresponds to the _n input units 11 _{-1 to} 11 _-n . It is composed of n coding units 12 _{-1 to} 12 _-n .
Each coding unit 12 _-i (i = 1 to n) has a corresponding input unit 1
The program data input from 1- _{i is} divided into data for each predetermined reproduction time, and the divided data is used as a unit for compression by the MPEG method (moving picture coding algorithm standardized by the Moving Picture Experts Group).

The FIFO unit 13 is a buffer that temporarily stores the compressed program data input from the encoding unit 12 until it is selected by the data selection unit 14, and n
N FIs corresponding to the respective coding units 12 _{-1 to} 12 _-n
FO unit composed of 13 _-1 to 13 _-n. Each FIFO unit 1
3- _i (i = 1 to n) is composed of a semiconductor memory,
It has a capacity capable of storing several pieces of program data which are divided and compressed for each predetermined reproduction time.

The data selection unit 14 includes n FIFO units 1
This is means for generating data for transmission from the program data sequentially stored in 3 _{-1 to} 13 _-n . The data selection unit 14
For example, when generating data for multi-channel transmission as applied to NVOD, m systems (m ≦ n) that are simultaneously input, compression-coded, and sequentially input to the FIFO unit 13 are generated.
Of the program data to be transmitted simultaneously is sequentially read from the FIFO unit 13 _-i (i = 1 to m), that is, selected to generate the transmission data so that they are continuously recorded. Output continuously.

The control section 15 is a control means for controlling the respective sections so that the data creating section 10 performs a desired operation, and is constituted by an ordinary arithmetic processing unit or the like. Further, the control unit 15 outputs a signal for instructing data writing to the I / F unit 22 of the data storage unit 20.

Next, the structure of the data storage section 20 will be described with reference to FIG. FIG. 3 is a block diagram showing the configuration of the data storage unit 20. The data storage unit 20 has a data recorder 21 and an I / F unit 22.

The data recorder 21 includes a data creating section 10
It is a large-capacity data storage device for recording the program data for transmission generated in (1). In the present embodiment, the data recorder 21 is a digital mass storage system in which a cartridge tape is used as a recording medium and a plurality of cartridge tapes can be automatically replaced.

This data recorder 21 has a recording capacity of about 36 Gbytes per cartridge tape, and one cartridge tape is used for the entire system.
Automatically handle 00 or more. Further, the data recorder 21 uses a head used in a D1-digital VTR device as shown in FIG. Since this head has a plurality of recording / reproducing heads, it is possible to record / reproduce data at high speed. As a result, in the data recorder 21 of the present embodiment, although the tape medium is used, 256 MBit / sec
Data can be read at the speed of.

The I / F unit 22 controls the data recording / reproducing process for the data recorder 21, and further transfers the recording / reproducing data to / from the data creating unit 10 or the data transmitting unit 30. That is, the I / F unit 22
Writes the transmission program data input from the data creation unit 10 to the data recorder 21 and outputs the transmission program data output to the data transmission unit 30 to the data recorder 21.
Read from. The writing and reading of the data are performed based on the writing signal from the control unit 15 of the data creating unit 10 and the reading signal from the program controller 33 of the data sending unit 30, respectively. In the data storage unit 20 of this embodiment, the data recorder 2
Reference numeral 1 denotes a recording device for recording data on a tape medium as described above, but the I / F unit 22 logically allows the data recorder 21 to access in file units like a normal disk. To control.

Next, the structure of the data transmission section 30 will be described with reference to FIG. FIG. 4 is a block diagram showing the configuration of the data transmission unit 30. The data transmission unit 30 includes the program library 31, the switcher 32, and the program controller 3.
3, sending unit 34, formatter 35, data exchange 3
6, sending controller 37 and schedule management unit 3
8

The program library 31 is a data recording means for recording the transmission data of the program to be distributed. Specifically, for example, in units of a period of 2 to 3 days, program data for transmission which is scheduled to be distributed within that period,
The data accumulating unit 20 stores the transmission program data that is not planned for distribution and is the transmission data of the program that is frequently requested by the receiver.
To transfer in advance. The program data for transmission recorded in the program library 31 is
It is appropriately transferred to the sending unit 34. In this embodiment, the program library 31 includes a plurality of magneto-optical (M
O) An MO changer device is used for automatically exchanging disks to record / reproduce data.

At the time of actual distribution of the program data, the switcher 32 transmits the program data for transmission transferred from the program library 31 or the program data for transmission directly transferred from the data accumulating section 20 to the p transmitting sections 34. _{-1 to} 34 _-p
It is a switching means for inputting into any of the sending units.

The program controller 33 transfers the program data for transmission from the data storage unit 20 to the program library 31, and directly transmits the program data for transmission from the data storage unit 20 to the transmission unit 34 via the switcher 32. The transfer and the transfer of the program data for transmission recorded in the program library 31 to the transmission unit 34 via the switcher 32 are controlled based on a control signal input from the schedule management unit 38. The data transfer from the data storage unit 20 is performed based on the read signal input from the program controller 33 to the I / F unit 22 of the data storage unit 20.

The transmission section 34 generates a plurality of program data to be transmitted to a plurality of channels from the inputted program data for transmission and outputs it to the corresponding formatter 35. The sending unit 34 is composed of p sending units 34 _{-1 to} 34 _-p ,
Each of the transmitters 34 _-i (i = 1 to p) further has q output channels.

The formatter 35 has p sending units 34 _-1.
P number of formatter that corresponds to ~34 _-p 35 _-1 ~35 _-p
It is composed of Formatter 35 _-i (i = 1 to p)
Attaches a header such as address information to the receiver who requested the data to the output data from each channel 1 to q of the corresponding sending unit 34 _-i (i = 1 to p), assembles an ATM cell, After multiplexing a large number of ATM cells, the ATM cells are output to the data exchange 36.

The data exchange 36 is connected to various transmission lines and actually transfers the data input from the formatter 35.

The sending controller 37 controls the sending unit 34, the formatter 35, and the data exchange 36,
Transfer of program data for transmission input via the switcher 32 to the transmission unit 34, and transmission from the transmission unit 34 to the formatter 35.
Data transmission to the request source via the data exchange 36, and the like, and transmission of program data to the request source are executed in synchronization. The sending controller 37 is configured by a general-purpose arithmetic processing device or the like.

The schedule management unit 38 is a control unit that manages and controls the entire data transmission device 1, and is composed of a general-purpose arithmetic processing device having an input / output unit with an operator such as a personal computer. The schedule management unit 38 uses the NVOD system for program transmission plans and V
The program controller 33 and the transmission controller 37 are based on an operation plan of the data transmission device such as a program preparation plan that can be provided as an OD system in response to a request from the receiver.
Control, and program data is transferred or sent as appropriate.

Next, the operation of the data transmission device 1 will be described with reference to FIGS. 6 and 7. In the present embodiment, the operation of creating data for sending and sending the data will be described in the case of sending a program with a reproduction time of 120 minutes as program data of 12 systems with a time difference of 10 minutes. . First, 12 VTR tapes on which the program A is repeatedly recorded a predetermined number of times are prepared, and 12 VTR reproducing devices 11 _{-1 to} 11 _-12 of the input unit 11 of the data creating unit 1 are prepared.
Play back the position shifted by 10 minutes each. This program A
Is divided into 120 pieces of partial data A1 to A120 of 1 minute each, the reproduction output signals Sa _{-1 to} Sa _-12 of the ₁₂ VTR reproduction devices 11 _{-1 to} 11 _-12 are as shown in FIG. .

This reproduction output signal Sa_-1~ Sa_-12Is compatible
Twelve encoders 12_-1~ 12 _-12Is input to M
It is PEG encoded. Signal Sb compressed by this_-1
~ Sb_-12Is shown in FIG. These signals Sb_-1~ Sb
_-12Is the corresponding 12 FIFO units 13_-1~ 13_-12To
Input sequentially. The data selection unit 14 includes 12 FIFs.
O part 13_-1~ 13_-12Signal Sb input to_-1~ Sb
_-12In order, select 12 types of program data
Data is generated so that the data is continuous.

Specifically, as shown in FIG. 7, the first
First 1 minute of program data A1 from the FIFO unit 13 _{-1 of}
Then, the program data A11 for one minute from 10 minutes to 11 minutes is selected from the second FIFO unit 13 _-2 . Thereafter similarly selects the program data of each FIFO unit 13 _-3 to 13 _-11 than 1 minute, and finally 12 th FIFO section 13 _{-1 2}
From 110 minutes to 110 minutes to 1 minute of program data A
Select 111. When the selection of the first program data from each of the FIFO units 13 _{-1 to} 13 _-12 is completed, the first FIFO data is again displayed
Returning to the O section _13-1 , the program data A2 for 1 minute from 1 minute to 2 minutes is selected. After that, the selection is continued in the same manner, and finally from the 12th FIFO unit 13 _-12 to 109 minutes to 110
One minute of program data A110 for one minute is selected, and generation of one program data for transmission is completed.

The generated program data for transmission Sc is
It is recorded in the data recorder 21 of the data storage unit 20.
Similarly, for other programs, program data for transmission is sequentially generated and stored in the data storage unit 20.

When the program A is transmitted as a provided program in the NVOD system, the program controller 33, based on a program transmission preparation instruction from the schedule management unit 38 of the data transmission unit 30, causes a few days before the transmission plan. First, the transmission program data Sc is transferred from the data storage section 20 to the program library 31 of the data transmission section 30.
When actually transmitting, the program data for transmission Sc recorded in the program library 31 is transmitted to the predetermined transmitting unit 3
4 _-i (i = 1 to p) is loaded into the data storage unit.

If the program A is not planned as a program to be provided in advance and is suddenly transmitted due to a request from the receiver or a sudden program change, the data read from the data storage section 20 is directly switched by the switcher. It is input to the sending unit 34 via 32. Transfer of these data is 256MB
It is read from the data recorder 21 at a speed of it / sec or more and transferred at a high speed.

In the sending section 34 _-i , the sending program data Sc recorded in the data storage section are sequentially read out, and the signals Sb _-1 to Sb _-12 shown in FIG. It is divided into system program data and is output to the formatter 35 _-i from 12 output channels. Then, the program data of the 12 systems is the formatter 35 _-i.
Are converted into a predetermined transmission data format, and transmitted via the data exchange 36.

Thus, the data transmission device 1 of this embodiment
In this case, since the video data can be immediately transferred from the data storage unit 20 to the recording unit in the sending unit 34 of the data sending unit 30 in response to the request, the program library according to the request of the receiver or a sudden program change. The program data not recorded in 31 can be immediately transmitted.

The data transmission apparatus of the present invention is not limited to this embodiment, and any suitable means may be used. Further, also in the data transmission device of this embodiment,
Various modifications are possible. For example, the configuration of the input section for inputting program data to the data transmission device is constituted by a VTR tape reproducing device in the present embodiment, and the data transmission device of the present embodiment targets the program data recorded on the VTR tape as the transmission object. It was something to do. However, the input unit is a unit for aligning the input program data into a predetermined format that can be handled by the encoding unit connected in the subsequent stage, and may be any unit according to the input program data.

More specifically, for example, in the case of inputting transmitted program data, a signal receiving device is used.
When it is desired to input a live scene image, a video camera device may be used as each input unit. Further, when a reproduction signal from a VTR device or a movie reproducing device, which is separately provided externally, is input, a program data format converter or a simple input signal adjuster may be provided as an input unit. .

Further, the compression coding method of the program data in the coding section of the data creating section is not limited to the MPEG system, and any method may be used for compression.

[0044]

According to the data transmission apparatus of the present invention, it is possible to set up program data for multi-channel transmission, which has been created and stored in advance, in a state in which it can be transmitted at high speed. As a result, It is possible to provide a data transmission device capable of immediately transmitting program data in response to a request from a receiver or a sudden program change.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a data transmission device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a data creation unit of the data transmission device shown in FIG.

FIG. 3 is a block diagram showing a configuration of a data storage section of the data transmission device shown in FIG.

4 is a block diagram showing a configuration of a data transmission section of the data transmission device shown in FIG.

5 is a diagram showing a structure of a recording / reproducing head of the data storage unit shown in FIG.

6 is a diagram illustrating program data reproduced by an input unit of the data creation unit shown in FIG.

FIG. 7 is a diagram illustrating transmission program data created by the data creation unit shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Data transmission device 10 ... Data creation part 11 ... Input part 12 ... Encoding part 13 ... FIFO part 14 ... Data selection part 15 ... Control part 20 ... Data storage part 21 ... Data recorder 22 ... I / F part 30 ... Data Sending section 31 ... Program library 32 ... Switcher 33 ... Program controller 34 ... Sending section 35 ... Formatter 36 ... Data exchange 37 ... Sending controller 38 ... Schedule management section 9 ... VTR tape

Claims (2)

[Claims] 1. Encoding means for respectively dividing a plurality of types of video data into data for each predetermined reproduction time, and compression encoding for each of the divided data, and each divided and compressed for each predetermined reproduction time. Creation of multi-channel transmission video data by making a plurality of types of encoded video data continuous for each data to be transmitted simultaneously and further arranging the continuous data in order of transmission time to create multi-channel transmission video data Means for recording and storing the created multi-channel transmission video data in a continuous storage area of a tape recording medium, the tape recording medium can be automatically replaced, and the recorded data can be continuously reproduced at high speed. And a multi-channel transmission video data continuously reproduced at high speed by the data storage means as recording data, Recording means capable of continuously and repeatedly reproducing, and continuously and repeatedly reproducing the multi-channel transmission video data recorded in the recording means and simultaneously transmitting the continuously recorded plural kinds of video data. A data transmission device having video data separating means for sequentially separating the generated data for each video data, and data transmitting means for transmitting the separated plural kinds of video data in parallel to a plurality of channels. 2. The data accumulating means comprises four reproducing heads, two reproducing heads provided adjacent to each other at opposite positions of the drum, and the reproducing heads facing each other at an angle of about 60 °. A rotary drum having four advanced playback heads, each of which is provided close to each other at two positions, and the stored video data for multi-channel transmission by playing back the tape recording medium by the rotary drum. The data transmission device according to claim 1, wherein the data is continuously reproduced at a high speed.