JPH1066038A - Broadcast system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly digital multi-channel broadcast by recording digitally coded stored system program data. SOLUTION: Storage system program data received by a video image transmission section 11 prior to broadcasting are coded in a storage system program transmission section 113 by the moving picture coding experts group(MPEG) system and stored in a hard disk drive(HDD) array. In this case, the data are coded with a high compensation rate without deteriorated image quality by using a coding rate depending on the contents of the source. In the case of broadcasting, the stored program data are reproduced and decoded and restored into a base band AV signal and it is given to a switcher 114, in which the signal is composited with another video and audio data to generate broadcast program data. Then a coding section 12 applies MPEG coding to the data at a coding rate depending on the broadcast system. In the case of coding by the coding section 12, the coding characteristic for the coding conducted for storage is referenced and the data are coded by the same characteristic as that at the coding to prevent deterioration in the image quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadcasting system for performing digital broadcasting.

[0002]

2. Description of the Related Art Digitalization is being promoted in various forms of broadcasting, such as cable television broadcasting, satellite broadcasting, and terrestrial broadcasting. In Japan, digital broadcasting systems are being studied, and services are being put to practical use.
In digital broadcasting, the amount of information of video data and audio data can be efficiently compressed. As a result, services such as high-quality video services and multi-channel broadcasting can be provided.

In such a multi-channel broadcast, in order to output program data recorded in advance on a plurality of channels, at present, as shown in FIG. The video tape on which the program is recorded is reproduced at the same time, and the reproduced program is transmitted to each channel. If automation is needed at that time,
As shown in (B), an arbitrary video tape can be set in an arbitrary VTR device using an autochanger. A method of recording broadcast program data in a hard disk drive (HDD) array as shown in FIG. 7 has also been considered. In that case,
Record program data in a state encoded for broadcasting,
The encoded data has a relatively low compression ratio (for example, video data is converted to JPEG format (Joint Photographic Image code).
Still Image Band Compression and Coding by ing Experts Group)
Recording the data (compressed to about 30 Mbps).

[0004]

However, in order to efficiently perform digital multi-channel broadcasting by a broadcasting system to which such a recording / reproducing apparatus is applied, there are problems in various points, and more appropriate There is a need for a broadcast system. In a recording / reproducing apparatus using a VTR apparatus as shown in FIG. 6, there is a problem that the reliability is not sufficient and the apparatus scale becomes large. Further, the recording / reproducing apparatus using the HDD array as shown in FIG. 7 requires a large-capacity HDD array, and has a problem that the apparatus scale is increased and the cost is increased. Also,
If the data is encoded and recorded at a low compression rate, the capacity of the HDD array must be further increased. Furthermore, if program data is recorded in a state where encoding for broadcasting has been performed in advance, switching to other video signals, key signals, and audio signals, and synthesizing processing cannot be performed during broadcasting, or encoding cannot be performed during transmission. There is a problem that the request for freely changing the rate (compression rate) cannot be answered.

Accordingly, it is an object of the present invention to store a large amount of digitally encoded program data, transmit digital multi-channels, and perform synthesis / edit processing with text and audio signals during broadcasting. It is to provide a possible broadcasting system.

[0006]

In order to solve the above-mentioned problems, a broadcasting system according to the present invention comprises a first system which encodes program data at a predetermined encoding rate by the same system as a digital encoding system at the time of broadcasting. Encoding device, a recording device for recording the encoded program data, a reproducing device for reproducing the recorded encoded program data during broadcasting, and a decoding device for decoding the reproduced encoded program data An editing processor for performing an editing process such as synthesis of text and audio on the decoded program data to generate broadcast program data; and converting the generated broadcast program data to the first program data.
A second encoding device that encodes at the encoding rate for broadcasting using the same digital encoding method as the encoding device of the above, and a sending device that sends the encoded broadcasting program data to a transmission path. .

[0007] Preferably, in the first encoding apparatus, although the encoding rate is higher than that at the time of broadcasting, even if decoding and re-encoding are performed by the same encoding method, image quality does not substantially deteriorate. The program data is encoded at a sufficiently low encoding rate. More preferably, the encoding rate is an arbitrary rate according to the type of program data.
Preferably, the second encoding device performs the encoding using information related to encoding such as information indicating a picture type at the time of encoding in the first encoding device. Also preferably, the broadcast system of the present invention has at least a plurality of the second encoding devices, and the transmission device includes a plurality of broadcast program data encoded by the plurality of second encoding devices. Are multiplexed as program data corresponding to a plurality of channels and transmitted on multiple channels.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a broadcasting system according to the present invention will be described with reference to FIGS. FIG. 1 is a block diagram illustrating a configuration of a digital multi-channel broadcasting system according to an embodiment of the present invention. The digital multi-channel broadcasting system 1 includes a digital multi-channel video transmitting unit 1
0, a multiplexing unit 20, a modulation unit 30, a transmission unit 40, and a broadcast output control unit 50. Further, the digital multi-channel video transmitting section 10 has a video transmitting section 11 and an encoding section 12.

First, the outline of the function and configuration of each unit constituting the digital multi-channel broadcasting system 1 will be described. The video transmission unit 11 of the digital multi-channel video transmission unit 10 performs a live program input based on a program transmission schedule from the broadcast output control unit 50,
The stored program data such as CM and promotion is output to each of a plurality of channels. The encoding unit 12 of the digital multi-channel video transmission unit 10 transmits the program data output from the video transmission unit 11 to the broadcast output control unit 5.
Encoding is performed based on an encoding control signal such as the number of audio channels or an encoding rate starting from 0, and output to the multiplexing unit 20.

The multiplexing section 20 adds multiplexed information to the encoded program data output from the encoding section 12 based on a control signal from the broadcast output control section 50 as necessary, and multiplexes the program data. And outputs the result to the modulation unit 30. Modulation unit 30
Converts the multiplexed program data input from the multiplexing unit 20 based on a control signal from the broadcast output control unit 50,
The signal is modulated into a signal suitable for the broadcasting system and output to the transmission unit 40. The transmission unit 40 transmits the signal modulated by the modulation unit 30 onto a transmission path based on a control signal from the broadcast output control unit 50, and actually performs broadcasting. The broadcast output control unit 50 includes:
Based on the program transmission schedule, the above-described units of the digital multi-channel broadcast system 1 are controlled so that a multi-channel broadcast signal having a desired program is output according to a desired schedule.

Next, a digital multi-channel video transmitting section 1
The configuration of 0 will be described in detail with reference to FIG. As described above, the digital multi-channel video transmission unit 10
Has a video transmission unit 11 and an encoding unit 12, and the video transmission unit 11 includes a live system program transmission unit 111, a CM
It has a promotion sending unit 112, a storage system program sending unit 113, a switcher 114, and a sending control unit 115. The encoding unit 12 has n MPEG encoders 121 _{-1 to} 121 _-n and an encoding control unit 122.

The configuration and function of each section of the digital multi-channel video transmission section 10 will be described. The live system program transmission unit 111 of the video transmission unit 11 receives real-time program data captured by a television camera and transmitted by wire, communication line, satellite communication, microwave, or the like. Output to the switcher 114 via an arbitrary output channel based on the control signal. The live program sending unit 111 has n0 output channels. The CM / promotion sending unit 112
A large number of short program data such as M and promotion are recorded in advance before broadcasting, reproduced based on a transmission schedule signal input from the transmission control unit 115, and output to the switcher 114 via an arbitrary output channel. I do. The CM / promotion sending unit 112 has n1 output channels. The configuration of the CM / promotion sending unit 112 is basically the same as that of the storage system program sending unit 113.

[0013] The storage system program sending section 113 is provided with a movie,
Program data, such as dramas and sports programs, which have already been recorded, are recorded in a recording device prior to broadcasting, reproduced based on a transmission schedule input from the transmission control unit 115, and switched via an arbitrary output channel. 11
4 is output. That is, the program which has been instructed at the instructed time is reproduced and transmitted to the instructed channel. The storage system program sending unit 113 has n2 output channels.

The structure of the storage system program sending section 113
(The same applies to the CM / promotion sending unit 112)
This will be described in detail with reference to FIG. Transmission of storage system program
The unit 113 includes k MPEG encoder units 131_-1~ 1
31_-k, K input control units 132_-1~ 132_-k, System
Controller 133, HDD array 13
4. n2 output control units 135_-1~ 135_-n2,and,
n2 MPEG decoders 136_-1~ 136_-n2Have
You. Each of the k MPEG encoder units 131 receives
MPEG data (Moving Picture coding
 (High quality video coding system by Experts Group)
Then, the encoded data is provided at the subsequent stage corresponding to each.
Input control unit 132_-i(I = 1 to k)
You. Input control unit 132_-i(I = 1 to k) is the corresponding M
PEG encoder 131 _-i(I = 1 to k)
The encoded data thus encoded is written to the HDD array 134.
Buffer at the recording unit and output at a predetermined timing.
You.

The system control unit 133 includes the transmission control unit 11
5 so that the input material data is encoded and recorded in the HDD array 134 based on the control signal from
PEG encoder units 131 _{-1 to} 131 _-k , input control unit 1
32 _{-1 to} 132 _-k and the HDD array 134 are controlled. Further, the HDD array 134 and the output control units 135 _{-1 to} 135 _{-1 to} 13-3 output desired program data at desired times.
5 _-k and the MPEG decoders 136 _{-1 to} 136 _-k are controlled. The HDD array 134 is a large-scale recording system using a plurality of hard disk devices. The HDD array 134 can perform recording and reproduction at a higher speed than a normal hard disk device, and further improves reliability by multiplexing and recording data. It is a thing. In the HDD array 134, processing such as recording processing, reproduction processing, and management of free space is performed by the system control unit 133, and input program data is recorded via the system control unit 133, and reproduced in response to a request. Is output.

The n2 output control units 135 _{-1 to} 135 _-1
-n2 is provided for each output channel from the storage system program sending unit 113, buffers the data read from the HDD array 134 by the system control unit 133, and supports the corresponding MPEG at a speed corresponding to the compression rate. Output to the decoder 136- _i (i = 1 to n2). The n2 MPEG decoders 136 _{-1 to} 136 _-n2 are
The encoded program data output from the output control unit 135 _-i (i = 1 to n2) is decoded, and the baseband program data is reproduced and output. At this time, the MPEG decoder 136
_-i (i = 1 to n2) outputs the coded information that has been coded together with the program data. Specifically, each picture of the program data is detected as a picture at the time of encoding, that is, a picture of I, P, or B of the MPEG system, and the information is added to the program data. Output. In the present embodiment, this information is added to an unused line in the vertical blanking of the program data and output.

The switcher 114 of the video transmitting unit 11
Based on control signals from the transmission control unit 115, input program data of the n0 channel from the live program transmission unit 111, the n1 channel from the CM / promotion transmission unit 112, and the n2 channel from the storage system program transmission unit 113 Thus, an output signal of the m channel is generated. The switcher 114 switches and combines the input program data as appropriate, performs editing by key input, and performs audio signal synthesis by external audio input, and generates an output signal of each channel.

The transmission control unit 115 includes a broadcast output control unit 50
The output of the program data in the live system program transmission unit 111 to the accumulation system program transmission unit 113 and the generation of the output signal in the switcher 114 are controlled based on the control signal from

The operation of the transmission control unit 115 will be described in detail with reference to the flowchart of FIG. First, the transmission control unit 115 performs an initial setting (step S1), and checks whether there is an instruction from the broadcast output control unit 50 to transmit a program or the like (step S2). If there is any instruction, it is checked whether or not the instruction is an end instruction (step S3). If the instruction is not an end instruction, the instruction is determined to be an instruction to transmit a program, and a specific transmission schedule (play list) is received from the broadcast output control unit 50 (step S4). This playlist has information such as a transmission program name, a reproduction start position, a reproduction start time, a reproduction output start time, and an output channel number of the switcher 114.

When the play list is received, an output instruction is issued to a program transmission unit which stores the program for which the transmission instruction has been issued or which can receive and transmit the program (step S5). Specifically, the program name, the reproduction start position of the program, the reproduction time, the reproduction output start time, the output channel number and the like are designated and controlled. Next, the transmission control unit 1
15 checks whether or not an instruction to the switcher 114 is necessary (step S6). If it is necessary, the output of the target program transmission unit is set to a desired output channel of the instructed switcher 114. The switcher 114 is instructed to output (step S7). When the instruction to the switcher 114 is completed, the process returns to step S6 to check whether or not the instruction to the switcher 114 is necessary.

If no instruction to the switcher 114 is required, the flow returns to step S2 to check again whether there is an instruction from the broadcast output control unit 50. Thereafter, when there is no need to input the instruction and control the switcher 114, the transmission control unit 115 repeats steps S2 and S6 and waits for one of them to occur.
If the control of the switcher 114 is necessary, the switcher 114 is controlled in step S7. Then, when an instruction to end a series of processes is input from the broadcast output control unit 50, the transmission control unit 115 performs an end process through steps S2 and S3 (step S3).
8), end the process (step S9).

The m MPEG encoders 121 _{-1 to} 121 _-m of the encoding unit 12 are provided corresponding to the m output channels of the switcher 114, respectively. Based on the output program signal M
Convert to PEG TS (Transport Stream). The encoding control unit 122 controls each of the MPEG encoders 121 _{-1 to} 121 _-1 based on a control signal from the broadcast output control unit 50.
Control _-m . Specifically, instructions such as the number of audio channels, the video encoding rate, and the audio encoding rate are given.

Next, the operation of the digital multi-channel video transmitting section 10 according to the present invention will be described with reference to FIG. FIG. 5 is a diagram showing a general flow of processing in the digital multi-channel video transmission unit 10. The digital multi-channel video transmission unit 10 encodes program data, which is input prior to broadcasting, by a MPEG method for programs other than live programs, and outputs the encoded data to the HDD array 1.
Record at 34. At this time, the compression rate is changed according to the contents of the program material, such as 6 Mbps for movies and dramas and 8 Mbps for sports programs.

At the time of broadcasting, the encoded program data is reproduced and read out from the HDD array 134.
Perform MPEG decoding processing. By this decoding process, baseband program data is generated. The characteristics at the time of encoding, that is, information indicating that each picture is an I picture or a P picture, are It is added to the program data and stored so that it can be referenced at the time of conversion. The switcher 114 synthesizes the key-input text and audio data, synthesizes the video data with other video data, and in some cases, edits or special effects processing the program data thus decoded. I do. Then, the final version of the program data for the broadcast having undergone such processing is encoded by the encoding unit 12 at an encoding rate of, for example, 3 to 6 Mbps according to the MPEG format.
Encode. In the encoding at this time, referring to the characteristics at the time of the first encoding, that is, information indicating that each picture is an I picture or a P picture,
Encoding is performed so as to have the same characteristics as the first encoding.

As described above, in the digital multi-channel broadcasting system 1 according to the present embodiment, program data to be broadcast is encoded at an encoding rate corresponding to the content of the program and stored in the HDD array. Therefore, each program data can be encoded at the most efficient encoding rate without deterioration in image quality. As a result, the recording device can be effectively used as a whole, the recording capacity can be minimized, and a compact and inexpensive storage device, that is, a broadcasting system can be constructed.

Also, at the time of broadcasting, the stored program data is decoded once and returned to the baseband signal, so that all necessary synthesizing processing and editing processing at the time of transmission can be performed. And since encoding for broadcasting is performed at the final stage, it can cope with changes in the encoding rate depending on the content of the program and adjustment of the encoding rate of each channel according to the limitation of the broadcast band and the number of transmission channels. it can. Furthermore, at the time of the re-encoding, since the characteristics of the encoding at the time of the first encoding are used, it is possible to substantially eliminate the image quality deterioration due to the two-time encoding, and it is possible to achieve high-quality broadcasting. Become.

The present invention is not limited to the embodiment, and various modifications are possible. For example, in the video transmission unit 11, the live program transmission unit 11
1. The configuration includes three program transmission units, that is, the CM / promotion transmission unit 112 and the storage system program transmission unit 113, but the present invention is not limited to this. The information may be combined into a live system and a storage system, or may be further subdivided according to the program material content. In addition, any processing such as synthesis and editing of broadcast program data performed by the switcher 114 may be performed. Further, an encoding method to be performed at the time of accumulation by the video transmission unit 11 and an encoding unit 12
In this embodiment, the encoding method performed by MPEG
Although the method has been described, any method other than the MPEG may be used.

Also, the M of the storage system program sending unit 113
The information at the time of encoding transmitted from the PEG decoder 136 to the MPEG encoder 121 of the encoding unit 12 may transmit any information at the time of encoding in addition to the information indicating the type of the picture. At that time, the method of adding the information may be any method other than the method of adding the information to the unused line in the vertical blanking as in the present embodiment. For example,
User data may be used as long as the data is SDI format. Also, without directly adding to the program data,
The information may be directly input to the encoding unit 12 that refers to the information. In addition, the specific configuration of each unit of the digital multi-channel broadcasting system 1 may be any configuration.

[0029]

According to the present invention, it is possible to store a large amount of digitally encoded program data at a low cost, at a low price, and to carry out digital multi-channel transmission with high reliability. And a broadcasting system capable of synthesizing / editing with a text or audio signal.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a digital multi-channel broadcasting system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a digital multi-channel video transmitting unit of the digital multi-channel broadcasting system shown in FIG.

FIG. 3 is a block diagram illustrating a configuration of a storage system program transmission unit of the digital multi-channel video transmission unit illustrated in FIG. 2;

4 is a flowchart showing a flow of processing of a transmission control unit 115 of the digital multi-channel video transmission unit shown in FIG.

FIG. 5 is a diagram schematically illustrating an operation of the digital multi-channel video transmitting section illustrated in FIG. 2;

FIGS. 6A and 6B are diagrams showing a recording / reproducing apparatus for program data in a conventional broadcasting system.

FIG. 7 is a diagram showing a recording / reproducing apparatus for program data which can be considered in a conventional broadcasting system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Digital multi-channel broadcasting system, 10 ... Digital multi-channel video transmission part, 11 ... Video transmission part, 12 ...
Encoding unit, 20 multiplexing unit, 30 modulation unit, 40 transmission unit, 50 broadcast output control unit, 111 live program transmission unit, 112 CM / promotion transmission unit, 11
3 ... storage system program sending unit, 114 ... switcher,
115 ... Sending control unit, 121 ... MPEG encoder, 1
22: encoding control unit, 131: MPEG encoder unit,
132 ... input control unit, 133 ... system control unit, 134
... HDD array, 135 ... Output control unit, 136 ... MPE
G decoder

Claims (6)

[Claims] 1. A broadcasting system for digital broadcasting, comprising: a first encoding unit that encodes program data having at least video data at a predetermined encoding rate by using the same encoding system as that used for broadcasting. A recording device for recording the encoded program data; a reproducing device for reproducing the recorded encoded program data; a decoding device for decoding the reproduced encoded program data; An editing processing device for performing predetermined processing on the decoded program data to generate broadcast program data; and encoding the generated broadcast program data in the same encoding scheme as that of the first encoding device. A broadcasting system, comprising: a second encoding device that encodes at a broadcast encoding rate by a method; and a transmission device that transmits the encoded broadcast program data to a transmission path. 2. The method according to claim 1, wherein the first encoding device decodes the encoded program data and then encodes the encoded program data again at the encoding rate for broadcasting using the same encoding method. The broadcast system according to claim 1, wherein the program data is encoded at the predetermined encoding rate that is sufficiently low without causing the program. 3. The broadcasting system according to claim 2, wherein said first encoding device encodes each of said program data at an arbitrary encoding rate according to a type of program data. 4. The broadcasting system according to claim 3, wherein said second encoding device performs said encoding using information relating to encoding at the time of encoding in said first encoding device. 5. The broadcast system according to claim 4, wherein the editing processing device combines the decoded program data with a predetermined signal including a text signal and an audio signal to generate the broadcast program data. . 6. A transmission apparatus comprising at least a plurality of said second encoding devices, said transmission device corresponding to a plurality of broadcast program data encoded by said plurality of second encoding devices. And multiplexing and transmitting the multiplexed program data.
Broadcast system as described.