JPH08205074A - Data transmitter - Google Patents

Abstract

PURPOSE: To provide a data transmitter in which even a live relay program is viewed by a viewer at a desired optional time during the relay of the program. CONSTITUTION: Program data received by a data transmitter 10 are compressed by an input section 20 and buffered in an FIFO memory and recorded in a recorder 40. The data are recorded in a prescribed format in the recorder 40 so that recording/reproduction is conducted continuously at a high speed and the data part by a prescribed time interval are sequentially consecutive. Then the plural data having already been recorded are reproduced by access consecutive to the recording. The plural reproduced data are decoded into original program data by an output section 50 and multiplexed and modulated at a multiplexer section 60 with the original live relay program data and sent as plural program data apart by a prescribed time interval from the live relay program data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission apparatus applicable to a video-on-demand (VOD) system, and more particularly to recording a live broadcast program, each of which has a predetermined time interval. The present invention relates to a data transmission device that can be reproduced and transmitted as a plurality of programs.

[0002]

2. Description of the Related Art A video-on-demand (VOD) system which sends out a program in response to a request from a receiver has a problem that the device is complicated and expensive. Therefore, the same program is reproduced in parallel at a predetermined interval such as an interval of 5 to 15 minutes, and the signal that starts reproduction at a predetermined interval is assigned to a request generated at an arbitrary time, and each request is assigned to each request. There is a way to respond. As a practical method, this method has begun to be widely used mainly in cable television broadcasting. This is the so-called near video on demand (NVOD) service. In addition, a service has been started to be provided in which a program reproduced at the time interval of 5 to 15 minutes is simultaneously transmitted using a plurality of channels so that a receiver can select an image of a predetermined channel.

[0003]

[Problems to be Solved by the Invention]
The OD or NVOD is a service for transmitting a pre-recorded program such as a movie, and for example, a live broadcast program (sometimes called a live program) such as a sports broadcast can be performed while the program is still being relayed. I couldn't watch the show from the beginning, that is, going backwards in time. In such a case, the only option is to watch the live broadcast program from the middle or to watch the recorded program after the relay is finished.

Therefore, an object of the present invention is to provide data which allows a viewer who is relaying a program to watch the program from an arbitrary time desired, even if the program is not recorded in advance as the program being live broadcast. It is to provide a delivery device.

[0005]

The recording device applied to the VOD or NVOD as described above may be recorded in a special format in order to simultaneously reproduce and send out a plurality of the same programs at a predetermined time interval. There were many. Then, in such a recording device, until now, it was not possible to reproduce on the same medium unless the data was recorded.
Therefore, in order to be applicable to the NVOD system, it is possible to reproduce while recording at a high speed in a predetermined format.

Therefore, the data transmission apparatus of the present invention is
Randomly accessible recording means, and simultaneously with recording the input program data in the recording means, a plurality of the recording means already recorded in the recording means and separated from the input program data by a predetermined time. It has a recording / reproducing means for reproducing the program data, and a data transmitting means for simultaneously transmitting the plurality of program data reproduced by the recording / reproducing means at the predetermined time intervals to a plurality of channels.

[0007] Preferably, the recording / reproducing means records the data, which are simultaneously recorded and reproduced at the predetermined time intervals, as one group in a continuous area, and further records each corresponding data between the groups. By assigning a recording area of the recording means and continuously scanning and accessing the recording means so that the groups are continuously recorded so that the data are arranged in time series, the input program data is predetermined. Each access unit is sequentially recorded in the group, and the program data already recorded in the group is reproduced by the continuous recording and the recording in each group.

Specifically, the recording / reproducing means erases data in a predetermined area in which subsequent data of the group is recorded by continuous access to the recording / reproducing for each group.

More specifically, the program data is any one of audio data, video data, and video data including audio data and video data.

[0010]

In the data transmitting apparatus of the present invention, the inputted program data is compressed to a predetermined rate and buffered in the FIFO memory. Then, recording / reproduction can be continuously performed at a high speed in the recording device at a predetermined transfer rate, and a plurality of reproduced data is recorded in a predetermined recording format such that the recorded data is separated from the recorded data by a predetermined time interval. I will do it. On the other hand, a plurality of data already recorded is reproduced by a series of accesses continuous with the recording.
The plurality of reproduced data are each decoded to be the original program data. If the program data is recorded according to the above format, the decoded program data is a plurality of data separated from the recorded data by a predetermined time interval. Then, these program data are simultaneously transmitted from different channels.

[0011]

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. FIG. 1 is a diagram showing the configuration of a data transmission device of the present invention. The data transmission device of the present embodiment is a data transmission device used for NVOD services, and, for example, at the same time as transmitting live broadcast programs such as soccer relay while recording live broadcast programs, shifts the live programs by predetermined time intervals. It is a device for further transmitting a plurality of program data. That is, as shown in FIG. 1, a material image of a sports relay transmitted by a communication satellite or an optical fiber cable is a data transmission device 1 of the present invention.
Input to 0. A plurality of images separated by a predetermined time t from the input live broadcast image are generated. Then, it is multiplexed with the original live broadcast video and again D by the communication satellite
It is delivered to each home by a TH (Direct To Home) service, a normal terrestrial broadcasting service, or a service using a wired network such as an optical fiber cable or a telephone line.

First, the configuration of the data transmission apparatus 10 of this embodiment will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the data transmission device 10 includes an input unit 20, a control unit 30, a recording device 40, an output unit 50, and
It has a multiplexer 60. FIG. 2 is a block diagram for explaining the configuration of the input unit 20, the control unit 30, and the output unit 50 of the data transmission device 10 shown in FIG. 1 in more detail. The video signal of the material input to the data transmission device 10 is input to the input unit 20 and the multiplexing unit 60.

The input unit 20 converts the input program data into
It is a recording signal generation unit that encodes, temporarily stores, and outputs at a predetermined timing. The input unit 20 of this embodiment includes an encoder 21, a FIFO memory 22, and a FIFO.
It has a control unit 23. First, the input unit 20 uses the encoder 21 to encode the program data that is continuously input using the program data of the predetermined time a as an access unit for each access unit a by a predetermined encoding method. The encoded program data for each period a is stored in the FIFO memory 22. Then, based on a control signal input from the control unit 30 to be described later to the FIFO control unit 23, the encoded program data is recorded via the control unit 30 at a predetermined timing.
Output to 0.

The encoding performed by the encoder 21 may be any moving image encoding method such as MPEG2. However, in the recording device 40 to be described later, assuming that program data of a predetermined period a is used as an access unit to perform writing and reading operations, assuming that the maximum number of program data to be read simultaneously is n, each writing and reading operation is performed. Must be performed at least during a period of 1 / n or less of the predetermined period a. Therefore, in the encoder 21, considering the data transfer rate,
It is necessary to compress the program data of the period a into a data amount that can be transferred in a period of 1 / n or less of the period a. In the present embodiment, the access unit a is 1 second, and the maximum number n of program data read simultaneously is 16.

The control unit 30 includes the data transmission device 1
It is a control means for controlling each of the above-mentioned units constituting 0. The control unit 30 of this embodiment includes a CPU unit 31, a ROM 3
2, a RAM 33, and a SCSI interface unit 34. The ROM 32 is a memory that stores a control program executed by the control unit 30.
The AM 33 stores parameters for performing this control. The CPU unit 31 controls the FIFO control unit 23 of the input unit 20 and the FIFO control unit 53 of the output unit 50 according to the control program. The SCSI interface unit 34 is an interface for performing data transfer with the recording device 40.

In the control unit 30, particularly as the control according to the present invention, the input data from the input unit 20 is recorded in the recording device 40, and the data already recorded in the recording device 40 is separated by a predetermined time t. It controls the process of reproducing as a plurality of data streams. Control of the recording / reproducing timing of this data and the recording format will be described later.

The recording device 40 is a recording device for actually recording program data, and is composed of an arbitrary randomly accessible recording device such as a hard disk device or a magneto-optical disk device. In the recording device 40, the writing of the input program data and the reading of a maximum of n pieces of program data that are shifted by a predetermined time t are simultaneously performed. This recording / playback processing is performed in a predetermined format, which will be described later.
It is controlled by the control unit 30 by a predetermined method.

The output section 50 is an output means for outputting a plurality of program data read from the recording device 40 and shifted by a predetermined time t to a plurality of channels, and n corresponding to the maximum number of channels read simultaneously. Individual output means 50a-
It consists of 50n. Each of the output units 50a to 50n has an F
It has an IFO memory 51, a decoder 52, and a FIFO control unit 53. In the output unit 50, the recording device 4
Program data sequentially read from 0 in units of access corresponding to a predetermined period a is stored in the FIFO memory 51. Then, the program data stored in the FIFO memory 51 is appropriately decoded by the decoder 52 and output. The FIFO control unit 53 writes data to the FIFO memory 51 and reads data from the FIFO memory 51 based on a control signal input from the control unit 30 so that output data is continuously secured. And control.

The multiplexing unit 60 is a sending means for sending the program data from the data sending apparatus 10 to the transmission path. The multiplexing unit 60 calculates a sum of n + of the input live broadcast program data and n program data obtained by shifting the live broadcast program data output from the output unit 50 by a predetermined time t.
One program data is multiplexed, modulated into a signal suitable for transmission, and sent to a predetermined transmission path. This multiplexing and modulation method may be any commonly used method.

Next, the recording device 40 of the data transmission device 10
Recording format of program data recorded in
Will be described with reference to. 3A and 3B are views for explaining the recording format of the program data recorded in the recording device 40 of the data transmission device 10. FIG. 3A is a diagram for explaining the program data, and FIG. 3B is a recording medium of the recording device 40. It is a figure which shows the recorded program data typically.

The input program data is a program of 160 minutes, and the access unit a for performing encoding / decoding and recording in the data transmitting apparatus 10 of this embodiment is 1
At the time of second, the 160-minute program data is divided into access units of 1 second and is represented as shown in FIG. That is, the 160-minute program data is the data labeled 0-00, which is the data for 1 second from 0 minutes 00 seconds,
159-5 which is the data for 1 second from 159 minutes 59 seconds
It is delimited by the data labeled 9. Then, in the data transmission device 10, the program data is transmitted for a predetermined time t = 10.
When the data is output in parallel while shifting by minutes, it is shown in FIG.
16 pieces of data of segment 0 to segment 15, which are program data for every 10 minutes as shown in, are simultaneously output from different channels.

As described above, in order to simultaneously output 16 segments in parallel, the program data corresponding to each segment must be accessed at high speed. For example, the first data segment 1 to segment 1
5 corresponding 16 pieces of data 0-00, 10-00, ...
.., 150-00 must be accessed within 1 second which is the reproduction time of each data access unit a.
Therefore, the recording method shown in FIG. 3B is a recording method in which the seek time and the search time are reduced and the corresponding data of each segment can be continuously accessed.

According to FIG. 3 (B), the program data for each second is 0-00, 10-0 on the spiral track.
0, ..., 150-00, 0-01, 10-01, ...
.., 150-01 are recorded in this order. That is, the first data, the second data, ...
... The corresponding data of the 600th data is continuously recorded as one group. When the data is recorded on the recording medium in such a format, the head can easily access the 16 program data which are shifted by 10 minutes by searching the data along the spiral.

Next, the recording device 40 of the data transmission device 10
First, the operation of recording and reproducing program data will be described with reference to FIGS. 4 and 5. As described above, the recording device 40 may be any randomly accessible recording device. However, when new data is overwritten on the area where data was recorded, a recording means that does not require erasing old data, such as a hard disk drive, and old data, such as a magneto-optical disk drive, are used. There is a difference in details between the operation of the recording device 40 and the recording means that requires the erasing operation. Therefore, here, the recording device 4 is provided for each of the hard disk and the magneto-optical disk.
The operation of 0 will be described.

First, the operation when the recording device 40 is composed of a hard disk device will be described with reference to FIG. FIG. 4 is a diagram for explaining an operation of recording and reproducing program data in a hard disk (HD) device,
(A) is a diagram showing a recording format, (B) is the first 1
The figure showing the state of recording data for 0 minutes, (C) is 20
Minutes to 30 minutes while recording data from 0 minutes to 10 minutes
It is a figure which shows the state which reproduce | regenerates the minute and the data for 10 minutes to 20 minutes. It should be noted that reference numeral W in the drawing indicates writing of data in the area, and reference numeral R indicates reading of data in the area.

First, when the program data for the first 10 minutes is input, the data for the 10 minutes is divided into 6 seconds by 1 second.
The data is divided into 00 access units and recorded in predetermined areas separated by 16 as shown in FIG. 4B. next,
When the recording for the first 10 minutes is completed, the head returns to the original recording start position, and the continuous access of the track as shown in FIG. 3B is performed again. At this time, the data of 10 minutes to 20 minutes is recorded while reproducing the data of 0 minutes to 10 minutes recorded previously. That is, the heads are sequentially accessed sequentially, and the heads are separated by 16 0-0.
The data of 0 to 9-59 is read, and the data of 10-00 to 19-59 is written in the area next to each data.

In the third data access, FIG.
As shown in (C), while reading the first two data in which the data of 0 minutes to 10 minutes and the data of 10 minutes to 20 minutes are already recorded in the data recording area divided into 16 parts, the third data is read. Write the data of 20 to 30 minutes in the area. Specifically, for example, 0-00, 10-00
After reading the data of, the data of 20-00 is written in the next area. After that, data access from 20 minutes to 160 minutes is similarly performed. Then, when all the data are input, all the program data are continuously recorded in the formats shown in FIG. 3 (B) and FIG. 4 (A).

Next, the operation when the recording device 40 is composed of a magneto-optical (MO) disk device will be described with reference to FIG. 5A and 5B are diagrams illustrating an operation of recording and reproducing program data in a magneto-optical (MO) disk device, (A) showing a recording format, (B) showing a state of performing initial erase, (C) is the first 10
FIG. 3D is a diagram showing a state in which data for a minute is recorded, and FIG. 7D is a diagram showing a state in which data from 0 to 10 minutes and data from 10 to 20 minutes are reproduced while recording data from 20 to 30 minutes. In the figure, reference numeral W indicates writing of data in the area, reference numeral R indicates reading of data in the area, and reference numeral E indicates erasing of data in the area.

When recording and reproducing program data on a magneto-optical (MO) disk, basically, the same as in the hard disk device, the corresponding data of 16 segments is recorded at a predetermined position so as to be continuous. However, in the case of magneto-optical (MO) disks, the data must be erased before writing the data. Therefore, first, before recording the program data, it is necessary to erase the data in the area where the program data is input for at least the first 10 minutes. The state is shown in FIG. When the erasing is completed, the head returns to the original recording start position, and FIG.
As shown in (C), the program data for the first 0 to 10 minutes is written. At this time, after recording the program data of 1 second each in a predetermined area separated by 16 pieces, the data of the area next to the recording area, that is, the area in which the data of 10 to 20 minutes is recorded by the next access Erase.

Even at the time of recording the data from 10 minutes to 20 minutes, the data of 10 minutes to 20 minutes is recorded while reproducing the previously recorded data of 0 minutes to 10 minutes, and further from 20 minutes to 30 minutes. The area for recording the data is erased. In the third data access, as shown in FIG. 5D, while reading the already recorded data of 0 minutes to 10 minutes, 10 minutes to 20 minutes in the data recording area divided into 16 pieces, Three
Data for 20 to 30 minutes is written in the second area, and the area for recording data for 30 to 40 minutes is erased.

Data access from 30 minutes to 150 minutes thereafter is similarly performed. And from the last 150 minutes to 16
Only when recording data up to 0 minutes, the erasing process is not performed, but the data recorded up to that time and the process of writing new data are performed. At the time when all the data are input, the data shown in FIG.
All program data is continuously recorded in the format shown in FIG.

As described above, in the data transmission apparatus 10 of the present embodiment, the program data to be live-relayed is recorded in the recording means while being live-relayed, and is shifted by a predetermined time t while being recorded in the recording means. Can be output.
The state of the output data is shown in FIG. As shown in FIG. 6, the live broadcast program started at time 0 is directly transmitted as a live program (live broadcast program), and
It is recorded on the recording medium in the above-mentioned format. Then, after a lapse of time t, and in the above-described example, after a lapse of 10 minutes, the data read from the data recorded on the recording medium can be transmitted as the time difference transmission program-1. After that,
Programs that are sequentially deviated by time t, that is, programs that are deviated by time 2t, 3t, ...

The data transmission device 10 as described above is used as an NVOD.
When it is applied to the system, for example, in sports broadcasting and theater broadcasting, in addition to live program channels, n time difference transmission program channels whose start time is delayed every predetermined time t minutes, in this embodiment, every 10 minutes are used. It is possible to prepare a book. Therefore, my plan,
You can watch the program from the beginning at your convenience.

The data transmission device of the present invention is not limited to this embodiment, and various modifications can be made. For example, the input unit 20, the control unit 30, the output unit 50
The configuration of each unit such as is not limited to this embodiment, and may be any configuration. For example, the control unit 30
May be configured by a computer device such as an ordinary personal computer or a workstation, and the interface with the recording device 40 is not limited to the SCSI interface, but may be any interface means capable of transferring predetermined data.

Further, as the recording device 40, magneto-optical (MO)
In the case where the disk device is used, in the above-described example, when the recording areas are sequentially accessed, the already recorded data is read, new data is written, and the area to be written next is erased. However, FIG.
An operation may be performed such that the data in all the areas are erased in advance at the time of erasing before the data input shown in (B). Then, the recording / reproducing process of the data performed at the same time as the input of the program data is the same as that of the hard disk device shown in FIG.

[0036]

According to the data transmitting apparatus of the present invention, while recording the input program data, it is possible to reproduce a plurality of program data separated from the already recorded program data by a predetermined time. . Therefore, it is possible to provide a data transmission apparatus suitable for use in the NVOD system so that the viewer can watch the program from any time desired even in the live broadcast program.

[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.

2 is a block diagram for explaining in detail the configurations of an input unit, a control unit, and an output unit of the data transmission device shown in FIG.

3A and 3B are diagrams for explaining a recording format of program data recorded in the recording device of the data transmission device shown in FIG. 1, FIG. 3A being a diagram for explaining program data, and FIG. It is a figure which shows the program data recorded on the medium typically.

4A and 4B are diagrams illustrating an operation of recording and reproducing program data in a recording device configured by a hard disk (HD) device, in which (A) shows a recording format and (B) shows the first 10 minutes. FIG. 6C is a diagram showing a state of recording data, and FIG. 7C is a diagram showing a state of reproducing data from 0 to 10 minutes and 10 to 20 minutes while recording data from 20 to 30 minutes.

5A and 5B are diagrams illustrating an operation of recording and reproducing program data in a recording device configured by a magneto-optical (MO) disk device, (A) showing a recording format, and (B) showing an initial erase. The figure which shows the state to perform, (C)
Is a diagram showing the state of recording data for the first 10 minutes,
(D) is a diagram showing a state in which data of 0 to 10 minutes and data of 10 to 20 minutes are reproduced while recording data of 20 to 30 minutes.

FIG. 6 is a diagram showing data transmitted from the data transmission device shown in FIG.

[Explanation of symbols]

10 ... Data sending device 20 ... Input part 21 ... Encoder 22 ... FIFO memory 23 ... FIFO control part 30 ... Control part 31 ... CPU part 32 ... ROM 33 ... RAM 34 ... SCSI interface part 40 ... Recording device 50 ... Output part 51 ... FIFO memory 52 ... Decoder 53 ... FIFO control section 60 ... Multiplexing section

Claims (4)

[Claims] 1. Randomly accessible recording means, and at the same time as input program data is recorded in said recording means, at the same time as said input program data already recorded in said recording means, every predetermined time. Data transmission including recording / reproducing means for reproducing a plurality of separated program data, and data transmitting means for simultaneously transmitting a plurality of program data reproduced by the recording / reproducing means at the predetermined time intervals to a plurality of channels. apparatus. 2. The recording / reproducing means records the data, which are simultaneously recorded and reproduced at the predetermined time intervals, as one group in a continuous area, and further records corresponding data between the groups. To record the groups continuously so that they are arranged in chronological order,
By allocating a recording area of the recording means and sequentially scanning and accessing the recording means, the input program data is sequentially recorded in the groups for each predetermined access unit, and the recording for each group is performed. 2. The data transmission device according to claim 1, wherein the program data already recorded in the group is reproduced by continuous access with. 3. The recording / reproducing means, by continuous access to the recording and reproducing of each of the groups,
3. The data transmission device according to claim 2, wherein data in a predetermined area in which data is recorded thereafter of the group is erased. 4. The data transmitting apparatus according to claim 1, wherein the program data is any one of audio data, video data, and video data including audio data and video data.