JPH11187310A - Digital data transmitting method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent modification such as commercial skip from being given to received data in digital broadcasting. SOLUTION: A queue information detecting circuit 23 detects queue information showing the position of a commercial (CM) part from digital broadcasting program stream transmitted to a branch station from a main station and a system controller 24 sends a queue information deleting signal to a queue information deleting block 25 based on this queue information and sends a CM insertion control signal to a CM insertion device 21. The device 21 select- switches a program transmitted from the main station and commercial from a queue server 22 according to a CM insertion control signal and sends it to the block 25. The block 25 deletes queue information from a broadcast signal from the device 21 and sends it out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital data transmission method and a digital data transmission apparatus for transmitting digital data such as a moving image signal and an audio signal.

[0002]

2. Description of the Related Art Conventional television broadcasting is based on terrestrial broadcasting which is configured to cover a wide area by a head office and a branch office.

FIG. 6 schematically shows the configuration of such a terrestrial broadcast.

[0004] The main station, which is the key, distributes the program material to each of the bureaus A, B, and C with a high quality by means of private transmission means, and each bureau distributes the final program to its respective broadcast area. I do.

[0005] From such an operation form, in terrestrial broadcasting, it is relatively easy to give a broadcast content a locality. Therefore, in the operation of terrestrial broadcasting, each branch station uses the above-mentioned regionality of broadcasting to convert a part of a program distributed from the main station into a program (local program) corresponding to a broadcasting area in charge. Broadcasting is performed instead.

[0006] In order to realize such program replacement, a splicing process for editing and combining a video stream and an audio stream is required.

[0007] FIG. 7 shows an example of the connection processing when a required program is replaced, as a part of a program for the whole country distributed from the head office at each branch office in each region. Shows a process of replacing a local program for a local area.

That is, the branch station transmits the main broadcast portion A of the broadcast program sent from the main station as it is, and replaces only a certain program material portion B with a local program material C prepared in advance for the reception area of the local station. Send out. And
After the transmission of the local program material C is completed, the main broadcast program A 'sent from the main station is transmitted again.

[0009] By such a method, the branch station can realize a broadcast with regional characteristics at low cost.

[0010] When the above-described program replacement processing is introduced into digital broadcasting, it is necessary to perform processing for combining the data stream sent from the main station and the data stream sent from the branch station.

Next, a conventional multiplexing system using a transport stream in digital broadcasting will be described.

FIG. 8 shows a transport system in which a plurality of programs are multiplexed on the transmitting side and sent out via a transmission medium, and the receiving side can selectively receive any of the plurality of programs. 1 shows a configuration example of a multiplexing system using a stream.

In this example, the transmitting side is a digital satellite broadcasting base station (uplink station), the transmission medium is a satellite broadcasting line, and the receiving side is a so-called set-top box for receiving satellite broadcasting.

On the base station side, each program (channel)
Are multiplexed by the video encoder and the audio encoder of the multiplexers 61a to 61n. Here, each program is, for example, MPEG (ISO / IEC IS1).
1172 and IS13818).

The bit stream of each program in which the video bit stream and the audio bit stream are put together is further multiplexed by the transport multiplexer 62a of the multiplexing device 62 and put into one transport stream. After that, the signal is modulated by the modulator 62b and sent to the transmission medium 63.

The transport stream transmitted to the viewer via the transmission medium 63 is demodulated by the demodulator 64a of the set-top box 64, demultiplexed by the demultiplexer 64b, and returned to a plurality of programs. Then, the program of the channel selected by the viewer with the remote controller 66 or the like is selectively taken out from the video decoder 64c.
And transmitted to the audio decoder 64d.

The signal is demodulated by the demodulator 64a of the set-top box 64,
The stream of the program demultiplexed by 4b is sent to the VTR device 67 and recorded.

The video and audio signals decoded by the video decoder 64c and the audio decoder 64d, respectively, and the stream recorded by the VTR 67 are output to a monitor 65.

As described above, in actual broadcasting such as digital satellite broadcasting, processing for editing and combining a video data stream and an audio data stream is required.

FIG. 9 shows how a video signal and an audio signal are multiplexed to form a transport stream.

FIG. 9A shows an original signal of an input video signal and audio signal. For example, in Japan and the United States, a video signal is configured as a moving image signal of one frame every 33 msec according to the NTSC system, and in other regions, it is 40 msec according to the PAL system.
Is configured as a one-frame moving image signal. The frame is a processing unit T _v of the video signal.

Similarly, about 1000 samples (depending on the bit rate) of an audio signal, which is called an audio frame, are set as a basic unit of processing T _A.

The original signal is converted into a target bit stream of several Mbps as shown in FIG. 9B by video encoding and audio encoding. Each unit of the video stream (video access unit) has a variable length, and each unit of the audio stream (audio access unit) has a fixed length.

Then, the encoded video bit stream and audio bit stream are packetized, multiplexed and reconstructed into a transport stream as shown in FIG. 9C. This transport packet is a fixed-length packet of, for example, 188 bytes and can include a plurality of programs.

On the other hand, the receiving side receives the above-mentioned transport stream which has been compression-encoded and multiplexed, and decodes it by performing the above-described processing in the reverse order.

FIG. 10 shows how a video signal and an audio signal are reproduced from the transport stream.

That is, as shown in FIG. 10 (a), a transport stream composed of multiplexed transport packets composed of video packets and audio packets is demultiplexed by a demultiplexer. The video bit stream and the audio bit stream shown in FIG. 10B are separated into elementary streams. Then, these bit streams are respectively decoded and shown in FIG.
It is output as a video signal and an audio signal as shown in (c).

[0028]

A digital broadcast signal transmitted as a transport stream as described above usually includes a cue signal used for editing program material. is there. However, if the cue signal is sent to the receiving side together with the program data, the receiving side may use the cue signal to easily process the program data.

The present invention has been made in order to solve such a problem, and does not require a significant change in the conventional digital data transmission method and digital data transmission apparatus. It is an object of the present invention to be able to prevent the processing of the.

[0030]

A digital data transmission method according to the present invention, proposed to solve the above-mentioned problems, comprises a detecting step of detecting position information indicating a position of a program material inserted in digital data; Erasing the detected position information, and transmitting the digital data from which the position information has been erased.

Further, a digital data transmission apparatus according to the present invention proposed to solve the above-mentioned problem comprises a detecting means for detecting position information indicating a position of a program material inserted in digital data, Erasing means for erasing information, wherein the digital data from which the position information has been erased is transmitted.

According to the present invention, when a branch station reorganizes a digital broadcast program and sends it to a viewer, the queue information including information on the in-point and out-point of the replacement part of the program material is deleted and transmitted. By doing so, it is possible to prevent digital broadcast data from being processed on the receiving side.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

Here, as an application example of the digital data transmission method and the digital data transmission apparatus according to the present invention, a case where the operation of the commercial skip function in digital broadcasting is not performed will be described.

In a conventional VTR device used for recording an analog television broadcast or the like, an audio track of a commercial portion of a broadcast signal is often set to a stereo audio mode, and a main program audio is recorded. Tracks are often set to double audio mode instead of stereo, so that the commercial part is detected, and processing such as not recording the commercial part on magnetic tape makes it possible for the commercial part to be reproduced during playback. A commercial skip function that prevents playback is implemented.

Also in digital broadcasting, it is desirable that all the various functions realized in the conventional analog television broadcasting are realized, and a method for realizing the functions has been proposed. In order to realize a commercial skip function in digital broadcasting which is one of them, it is conceivable to detect a commercial part using cue information included in a digital broadcast signal.

The embodiment of the present invention described below assumes that a commercial skip function in digital broadcasting operates using a cue signal included in a broadcast signal, and the cue information is finally transmitted to the receiving side. This is to prevent the operation of the commercial skip by not sending it.

FIG. 1 shows that a commercial part inserted in a transport stream of a digital broadcast sent from the head office is replaced with another commercial by using a cue information at a branch office, and that the digital broadcast is transmitted by a VTR device or the like. 9 shows a basic process of the digital data transmission method according to the present invention, which detects a commercial portion during recording / reproduction and processes the data so that it cannot be skipped, and transmits the processed data.

The broadcast signal transmitted from the head office includes the signals shown in FIG.
As shown in (a), the commercial part CM is inserted, and prior to this, the queue information 102 including the information of the In (In) point and the Out (Out) point of the commercial part CM is sent. The broadcast signal from the head office is transmitted to the branch office by a private program transmission means.

On the other hand, on the branch side, as shown in FIG. 1B, the position of the commercial CM is specified using the queue information 102, and the commercial CM is replaced with a local commercial CM 'for each region. It performs a process called an application.

The broadcast signal subjected to the commercial insertion is included in the broadcast signal as shown in FIG. 1 (c) when the broadcast signal is transmitted from the branch station to the viewer in the broadcasting area in charge. Queue information 102 is deleted. The elimination of the cue signal is performed by deleting the original cue signal 102 and stuffing appropriate dummy data 103 or filling in 0 (Null) information, so that information on the in-point and out-point is transmitted from the branch station to the viewer. This is processing to prevent transmission.

By performing the above processing at the branch station, it is possible to prevent the commercial portion from being skipped by using the cue information when the viewer records / reproduces the digital broadcast using a VTR device or the like.

FIG. 2 shows an example of the configuration of a digital data transmission apparatus according to the present invention for preventing the above-described commercial skip from functioning on the digital broadcast viewer side.

The broadcast signal transmitted from the main station by the private program transmission means and received by the branch station is first input to the commercial insertion device 21. The commercial (CM) insertion device 21 converts a broadcast signal sent from the head office and a commercial (CM) server 22 storing local commercial materials prepared at the branch office side into a commercial (CM) insertion described later. It operates as a switch that switches according to a control signal.

The broadcast signal received by the branch station is also supplied to a cue information detection circuit 23, and from the cue information detected here, information on the in-point and out-point of the commercial part is sent to the system controller 24. Sent.

The system controller 24, in accordance with the result of the cue information detection by the cue information detection circuit 23, controls a commercial insertion control signal for switching the commercial insertion device 21 and a cue information deletion block to be described later. A queue information deletion signal for controlling the operation is output.

The broadcast signal output from the CM insertion device 21 contains cue information. For this reason, the above-described process of crushing the cue information is further performed to make the broadcast signal finally transmitted to the viewer.

More specifically, the system controller 24
Sends a cue information deletion signal to the cue information deletion block 25 and deletes the cue information by performing an operation such as crushing the cue information in the stream of the broadcast signal by stuffing.

Then, the broadcast signal generated in this way is transmitted to a broadcast area covered by the own station.

Next, the actual operation of the commercial insertion described above will be described.

FIG. 3 shows how cue information is used when performing a commercial insertion.

The commercial C of the main broadcast sent from the head office
In order to replace M with a local commercial CM 'at the branch office (local office), commercials from the main office (In)
Cue information 10 indicating a point and an out point
2 is PSI (Program Specific Information) 101
As a special information packet to the branch office.

On the branch station side, the main broadcast portion A from the main station is transmitted as it is while the P corresponding to the cue information 102 is transmitted.
Upon receiving the SI packet 101, the PSI packet 101
, The position of the in-point and out-point of the commercial part CM is specified using information such as pointers to the in-point and the out-point included in. Then, by referring to these pieces of information, only the portion between the specified in-point and out-point is replaced with the local commercial CM 'and transmitted. As a result, commercial insertion at the branch office is realized.

On the other hand, in order to realize the function of skipping the commercial part inserted in the transport stream on the receiving side, (1) broadcast reception is performed continuously, and the commercial part is skipped during reproduction; 2) There are two types of systems, namely, a system in which a commercial portion is specified and skipped during broadcast reception and recorded. In the following, the digital data transmission according to the present invention will be described by taking the above-mentioned method (1) in which a broadcast program is received as usual, continuously recorded on a recording medium, and only a commercial portion is skip-reproduced during reproduction. A method and a case where a digital data device is applied will be described.

FIG. 4 shows an operation in which the VTR device on the receiving side uses the cue information to skip the commercial part inserted in the transport stream of the digital broadcast and reproduce it.

In this system, a broadcast program is continuously received and recorded on a recording medium as it is. At this time, FIG.
As shown in (a), a packet in which the queue information 11 is written (PSI packet) and a commercial part CM are also:
All are recorded on a recording medium.

On the other hand, when reproducing the transport stream of the above-mentioned broadcast program recorded on the recording medium, the cue information 11 is monitored simultaneously with the reproduction, as shown in FIG. The information of the in-point and the information of the out-point described in (1) are extracted, and the area from the in-point to the out-point is skipped by a fast forward (FF) operation. As a result, only the main broadcast part A and the main broadcast part A 'are reproduced.

FIG. 5 shows an example of the configuration of a conventionally proposed digital data recording / reproducing apparatus for realizing the commercial skipping system described above.

All the information sent from the broadcasting station is received by the receiving circuit 30 and is transmitted to the tape drive 3 such as a VTR device.
1 is recorded on the magnetic tape 35. At the time of reproduction, the stream is read from the magnetic tape 35 by the tape drive 31, decoded by the decoder 33,
The reproduced signal is output to the monitor 36 or the like.

At this time, the reproduction data read by the tape drive 31 is also supplied to the cue information detection circuit 32. The cue information detection circuit 32 checks the positions of the in-point and out-point of the commercial part from the cue information in the reproduction data stream to generate a read control signal,
The tape drive 31 is controlled so as to skip the commercial part.

According to such a digital data recording / reproducing apparatus, a commercial skip at the time of reproduction is realized on the digital broadcast receiving side. However, since a broadcaster that sends out a broadcast program is in a position to obtain advertising revenue by sending a commercial to a viewer, it is necessary to suppress or prevent the above-described commercial skip from being easily realized.

In the above case, if the present invention is applied, the broadcast signal is processed so that the commercial skip is not realized on the receiving side with almost no change in the conventional digital data transmission method and digital data apparatus. It can be sent.

[0063]

As described above, according to the digital data transmission method and digital data transmission apparatus of the present invention, the editing position included in the stream of the broadcast signal transmitted from the head office to the branch station (local station) is indicated. Queue information,
Since the data is transmitted to the receiving side after being deleted at the branch station, it is possible to prevent the receiving side from easily processing the digital broadcast data.

It should be noted that the application of the present invention is not limited to the example of preventing the commercial skip on the receiving side of digital broadcast data as described above, and the receiving side utilizes the edit signal included in the transmitted digital data. This is effective for suppressing various editing operations that can be performed.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a basic process of a digital data transmission method according to the present invention.

FIG. 2 is a diagram showing a configuration example of a digital data transmission device according to the present invention.

FIG. 3 is a diagram for explaining how queue information is used when performing a commercial insertion.

FIG. 4 is a diagram for explaining an operation of reproducing by skipping a commercial part inserted into a transport stream of digital broadcasting using cue information.

FIG. 5 is a diagram showing a configuration example of a digital data recording / reproducing apparatus for realizing a commercial skipping method.

FIG. 6 is a diagram schematically showing a configuration of a conventional terrestrial broadcast.

FIG. 7 is a diagram for describing stream joining processing;

FIG. 8 is a diagram illustrating a configuration example of a multiplexing system using a transport stream.

FIG. 9 is a diagram for explaining how a video stream and an audio signal are multiplexed to form a transport stream.

FIG. 10 is a diagram for explaining how a video signal and an audio signal are reproduced from a transport stream.

[Explanation of symbols]

21 commercial (CM) insertion device, 2
2 commercial (CM) server, 23 queue information detection circuit, 24 system controller, 25 queue information deletion block

Claims (10)

[Claims] A detecting step of detecting position information indicating a position of the program material inserted in the digital data; and an erasing step of erasing the detected position information.
A digital data transmission method comprising transmitting digital data from which the position information has been deleted. 2. The digital data transmission method according to claim 1, wherein the position information includes start point position information and end point position information of the inserted program material. 3. The system according to claim 1, further comprising a material replacement step of replacing the program material with another program material, wherein the digital data in which the program material is replaced with another program material is transmitted. Digital data transmission method. 4. The digital data processing system according to claim 1, further comprising a replacement step of replacing the erased position information with other information, and transmitting digital data in which the position information is replaced with other information. Data transmission method. 5. The digital data transmission method according to claim 1, wherein the inserted program material is a commercial material. 6. A detecting means for detecting position information indicating a position of a program material inserted in digital data, and an erasing means for erasing the detected position information,
A digital data transmission device for transmitting digital data from which the position information has been deleted. 7. The digital data transmission apparatus according to claim 6, wherein the position information includes start point position information and end point position information of the inserted program material. 8. The system according to claim 6, further comprising material replacement means for replacing said program material with another program material, and transmitting digital data in which said program material is replaced with another program material. Digital data transmission equipment. 9. The digital data processing system according to claim 6, further comprising a replacement unit for replacing the erased position information with another information, and transmitting digital data in which the position information is replaced with other information. Data transmission device. 10. The digital data transmission apparatus according to claim 6, wherein said inserted program material is a commercial material.