JP3983649B2 - Digital broadcast receiver - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital multi-channel broadcasting system, and more specifically to a program transmission / reception method and its reception / playback apparatus.
[0002]
BACKGROUND OF THE INVENTION
Digital multi-channel broadcasting can broadcast 4 to 8 channels in one carrier frequency band by multiplexing and transmitting program data obtained by compression-coding video and audio signals. Currently, a CS digital multi-channel broadcasting system using a communication satellite (hereinafter referred to as CS) as a relay station is in operation. In this system, by using data compression according to the MPEG2 standard for program data, video broadcasting of 50 channels or more and audio broadcasting of 100 channels or more can be distributed by one CS. For reception, a dedicated reception / playback apparatus is required, and the digital data of the program desired by the user is decoded from the received signal in real time to reproduce the video / audio signal of the program.
[0003]
In the CS digital multi-channel broadcasting system, there is a distribution method called pay-per-view (hereinafter referred to as PPV) in which a program viewed by a user is charged in units of one or time. The viewing information of the PPV program is stored in an IC card set in the IC card interface unit of the reception / playback apparatus, and is transmitted to the broadcasting station via a telephone line at an appropriate communication opportunity. The broadcasting station collects a viewing fee by a method such as automatic transfer based on this viewing information. This makes it possible to view video software as if it were a rental video while at home.
[0004]
Further, Japanese Patent Laid-Open No. 6-204954 discloses a method for receiving a user request and distributing a PPV program. In this case, a broadcast station receives a user's request via a telephone line connected to the reception / playback apparatus, and the broadcast station transmits program data in the order of request. For distribution, data is distributed in a short time by using the entire carrier frequency band of one transponder. Alternatively, different program data is distributed simultaneously for each channel. Then, the distributed program data is stored in the data storage unit of the reception / playback apparatus. The user reads out and reproduces the stored program data as appropriate.
[0005]
DISCLOSURE OF THE INVENTION
The present invention was created based on the recognition of the technical situation and the social situation as described above. According to the program transmission / reception method of the present invention, on the transmission side of a digital multi-channel broadcasting system, program data formed by compressing and encoding video / audio signals constituting a program is divided into a number of blocks and block numbers are assigned to the blocks. As a format of the added program block, it is repeatedly transmitted serially at a low bit rate over a longer time than the recording time of the program, and on the receiving side, the program block is repeatedly transmitted serially at a low bit rate. A first storage process for receiving a sequence from a block number in the middle of a program to a block number at the end of the program in a storage unit, and a first storage process for storing from the block number at the beginning of the program to the block program in the middle of the program in a storage unit. After the storage process of 2 and a large number of program blocks constituting the program are arranged in the storage unit, The these program blocks being decrypted by reading in the order of block numbers, it is characterized in that for reproducing video and audio signals constituting a program.
[0006]
The digital broadcast receiving apparatus according to the present invention is specified by the following items (1) to (11).
(1) The reception demodulating means, the demultiplexing means, the decoding / reproducing means, the control means, the storage means, and the digital broadcast receiving apparatus provided with the user interface. (2) The reception demodulating means is the control means. (3) The demultiplexing means demultiplexes the television program stream and the low bit rate data stream multiplexed in the television program stream from the output of the receiving demodulation means. (4) The decoding / playback means can decode the TV program stream output from the demultiplexing means and output a video / audio signal, and can also decode the video / audio program stream read from the storage means under the control of the control means. (5) The low bit rate data stream constitutes a video / audio program. (1) A video / audio program stream including a low-bit-rate video / audio program stream that includes compression-encoding of the video / audio signal is included (6) One video / audio program is composed of a number of blocks included in the low-bit-rate data stream (7) ) A large number of blocks constituting one video / audio program include a common program number for specifying the video / audio program and a block number for defining an arrangement order of the blocks, and the block is defined in the low bit rate data stream. Appearing periodically and repeatedly over a longer time than the recording time of the video / audio program (8) The control means enables collection processing, notification processing, and reproduction processing (9) The collection processing is stored in the storage means. When program number A is stored as a reserved viewing program, the program number A is blocked from the low bit rate data stream output by the demultiplexing means. (10) The notification process indicates that the reserved program can be viewed through the user interface when blocks having all block numbers of program number A are stored in the storage means. (11) In the reproduction process, when a viewing request for the program number A that can be viewed is input from the user interface, each block of the program number A is read from the storage means in the order of the block number at a high bit rate. Supplying to the decoding / reproducing means, and outputting the video / audio signal from the decoding / reproducing means.
DETAILED DESCRIPTION OF THE INVENTION
A CS digital multichannel broadcasting system using CS as a relay station will be described as an embodiment of a digital multichannel broadcasting system including a program transmission / reception method and a reception / playback apparatus according to the present invention. FIG. 1 is a basic configuration diagram thereof, which includes a broadcasting station 1, a CS 10, and a reception / playback device 20. The broadcasting station 1 and the receiving / reproducing apparatus 20 are connected by a telephone line 40. These basic configurations are exactly the same as in conventional CS digital multi-channel broadcasting.
[0008]
FIG. 2 is a configuration diagram of the data stream 100 distributed by the program transmission / reception method according to the embodiment of the present invention. A large number of program blocks 110 and a program list 120 inserted as appropriate between the program blocks 110 are included. The program block 110 is obtained by dividing program data obtained by compressing and encoding a video / audio signal of a program by the MPEG2 system into a plurality of data for each fixed data length. A program number 111 and a block number 112 are added to the program block 110. A large number of program blocks with the same program number are serially distributed in the order of the block numbers. The program list 120 is list data of programs distributed during a predetermined period. Corresponding to the program number, classification information such as program name and genre, distribution time information indicating the total number of program blocks to be distributed and the distribution start and end times of the program blocks are added.
[0009]
Furthermore, in this embodiment, the transfer speed at the time of distribution is sent at a low bit rate over a very long time compared to the recording time of the program. Therefore, about 5 to 8 programs are distributed in about 120 hours. When the distribution of the program blocks of all the programs is completed, the same program block is distributed again by returning to the first program number. During the predetermined period, the same program is continuously distributed in this way. The program list is appropriately inserted between program blocks at intervals of about 5 seconds. Of course, the distribution time information in the program that is being transmitted or has been transmitted is rewritten and distributed to the time information distributed in the next cycle.
[0010]
The distribution of a plurality of programs in one carrier frequency band is basically the same as the conventional CS digital multi-channel broadcasting. The concept of the multiple processing system is shown in FIG. The data stream consisting of the program block and program list distributed in this embodiment is multiplexed together with various auxiliary data such as video / audio data such as ordinary TV programs and program identification codes, and sent out on one channel. The A plurality of channels transmitted in the same carrier frequency band are multiplexed. Here, scramble data is added as necessary. These digital data are QPSK modulated and sent to CS. Here, the data stream is transferred at a low bit rate because it is multiplexed with other data such as a TV program broadcast on one channel. Of course, a plurality of the above-described data streams may be multiplexed on one channel.
[0011]
FIG. 4 is a block diagram of the reception / playback apparatus 20 in this embodiment. An intermediate frequency (IF) signal received / converted by a parabolic antenna or the like is input, and a central control device 21 including a RAM and a ROM controls peripheral devices and the like through a bus 22 to input / output data. The reception / playback apparatus 20 is controlled. Hereinafter, control of the reception / reproduction device 20 by the central control device 21 will be described. When a user's program selection operation is received from the remote controller 34 or the operation input unit 24, the tuning unit 25, the demodulation unit 26, and the demultiplexing unit 27 are controlled. It tunes to the IF of the carrier wave containing the selected program, demodulates the program multiplexed data in which a plurality of programs are multiplexed from the carrier wave, and demultiplexes it into the program data of each channel. The demultiplexer 27 is controlled so as to perform error correction and descrambling as necessary. Then, the MPEG2 decoding unit 28 is caused to decode the video / audio signal. The video / audio signals are input to a TV receiver or the like via the video / audio control units 29 and 30, respectively. The above is the reproduction control of normal TV program data.
[0012]
In addition to the above-described TV program playback function, the reception / playback apparatus 20 in this embodiment also has a function of processing data streams multiplexed on the same channel. Upon receiving a list display command from the remote controller 34 or the operation input panel 24, the central control unit 21 displays the program list in the data stream separated together with the TV program data by the demultiplexing unit on a display such as a TV receiver. At the same time, a list is also displayed on the display panel installed in the receiving / reproducing apparatus 20. Since the program list is sent out at intervals of about 5 seconds as described above, the user can see the list after waiting for about 5 seconds at the maximum. When the user operates the remote controller 34 or the operation input unit 24 to specify a program to be viewed from the list, the central control device 21 stores the program number and stores the program block with the program number in the hard disk device 23. . If the program data is already being distributed at the time of reservation, program blocks from the middle are accumulated. Since the transmission cycle of all program blocks is about 120 hours (5 days), all program blocks of the program to be viewed are surely stored in the hard disk device 23 after 5 days. When all the program blocks of the reserved program are accumulated, the fact is notified to the user. In this embodiment, a storage completion lamp installed in the operation input unit is turned on. When the program list is displayed on the display, the program column is displayed in reverse video to notify that viewing is possible. Furthermore, control is performed so that duplicate reservations for the program are not accepted. Then, the program data including all the program blocks is read from the hard disk device 23 in the order of the block numbers in response to the user's operation input, and transferred to the MPEG2 decoding unit 28 at the same transfer speed as that of normal TV broadcasting. The MPEG2 decoding unit 28 decodes the video / audio signal and reproduces the program.
[0013]
On the other hand, the receiving / reproducing apparatus 20 according to the present embodiment also has a function of obtaining the viewable date / time of the program distributed from the distribution time information included in the program list and displaying it in the list of the program list. FIG. 5 shows a list displayed on the display. In the figure, the No. 7 program is being distributed, and when No. 7 is reserved, the subsequent program blocks are accumulated in the hard disk device 23. Then, the first program block before the reservation time is accumulated at the time of delivery of the next cycle in which all programs have completed one cycle.
[0014]
Further, it has a function of searching and reserving a program desired by the user using the classification information in the program list as a key. FIG. 6 shows a program reservation screen using the search function. When the user selects and inputs a desired genre, the title is displayed if the desired genre is in the distribution schedule. The classification information is not limited to the genre, but can be freely set by simply adding it to the program list, such as the performer and the country of production (production company in the case of Japanese movies). In this case, a free search such as a logical product search or a logical sum search is possible using a plurality of classification information as keys.
[0015]
It is assumed that most of the programs distributed in this embodiment are distributed by the PPV method. Next, the reception / reproduction control linked to the billing system in the case of PPV will be described. FIG. 7 shows a flowchart of processing performed by the central control device 21 of the reception / playback device 20 when the PPV program is distributed. In the program list, information indicating whether the program is PPV and the viewing deadline information of the program are added. If the program reserved for viewing by the user is PPV, deadline time information is acquired from the program list, and program blocks of the program are accumulated in the hard disk device 23 (201 to 204). When all the program blocks stored by the user's operation are reproduced, the program data stored in the hard disk device 23 is deleted. Then, it is determined whether the reproduction end date has passed the deadline (205-208). If it exceeds, the excess charge is calculated according to a predetermined rule (209). The viewing fee information is written into the IC card 31 via the IC card interface unit 32 and transferred to the broadcasting station at an appropriate communication opportunity (211 and 212). Note that the information written in the IC card 31 may be only the viewed program and the viewing time. In this case, the viewing fee is calculated by the broadcasting station.
[0016]
In this embodiment, a hard disk device is used as means for storing program data and the like, but a rewritable DVD or the like may be used as a larger capacity storage medium.
[0017]
【The invention's effect】
According to the present invention, since the program data obtained by compressing and encoding the audio / video signals constituting the program is transmitted at a low bit rate over a longer time than the recording time of the program, it is occupied for the distribution of the program data. Since the frequency band to be used is small, it is possible to greatly reduce the communication cost, and it is possible to multiplex and distribute together with a normal TV program as necessary.
[0018]
In addition, program data in the form of a program block that is divided into a large number of blocks and each added with a block number is repeatedly transmitted serially at a low bit rate over a longer time than the recording time of the program. The receiving side receives a program block sequence that is repeatedly transmitted serially at a low bit rate, and stores in the storage unit from the block number in the middle of the program to the block number at the end of the program, and the program head Through a second accumulation process for accumulating in the storage section from the block number of the program to the block program in the middle of the program, after the program blocks constituting the program are arranged in the storage section, the program blocks are arranged in block number order. Since the video and audio signals that make up the program are played back and decoded, the program data start time It is not necessary to start data accumulation after waiting for the program to start, and data accumulation can be started at any time while program data is being distributed, and the shortage at the beginning of the program is replenished at the time of distribution repeatedly. Blocks can be aligned, and instead of distributing program data at a low bit rate over a longer time than the program recording time, the waiting time until the program can be viewed can be shortened.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a digital multi-channel broadcasting system in an embodiment of the present invention.
FIG. 2 is a data structure diagram of a program distributed in the embodiment.
FIG. 3 is a system diagram showing a method for multiplexing programs distributed in the embodiment.
FIG. 4 is a configuration diagram of a reception / playback apparatus according to an embodiment of the present invention.
FIG. 5 is a schematic diagram showing a program list display screen including a viewable date and time in the receiving and reproducing apparatus of the present embodiment.
FIG. 6 is a schematic diagram showing a display screen for searching for a program in the receiving and reproducing apparatus of the present embodiment.
FIG. 7 is a flowchart showing reception / reproduction control linked to a charging system in the reception / reproduction apparatus of the present embodiment.
[Explanation of symbols]
1 Broadcast Station 20 Reception / Playback Device 21 Central Control Device 23 Hard Disk Device 28 MPEG2 Decoding Unit 100 Data Stream 110 Program Block 120 Program List

Claims (1)

A reception device for receiving a demodulating signal, a demultiplexing unit, a decoding / reproducing unit, a control unit, a storage unit, and a user interface,
The reception demodulation means receives and demodulates the broadcast stream of the designated channel according to the control of the control means,
The demultiplexing means separates the television program stream and the low bit rate data stream multiplexed in the television program stream from the output of the receiving demodulation means,
The decoding / playback means can decode the TV program stream output from the demultiplexing means and output a video / audio signal, and can also decode the video / audio program stream read from the storage means under the control of the control means to output the video / audio signal. Output is possible,
The low bit rate data stream includes a video / audio program stream in which a video / audio signal constituting a video / audio program is compression-coded and the bit rate is reduced,
One video / audio program is composed of a number of blocks included in a low bit rate data stream,
A large number of blocks constituting one video / audio program include a common program number for specifying the video / audio program and a block number for defining an arrangement order of the blocks, and the video is included in the low bit rate data stream. Appears repeatedly over a longer period of time than the recording time of the audio program,
The control means enables collection processing, notification processing, and reproduction processing,
Collection process, if the turn group number A in the storage means is stored as the viewing reserved program sequentially stored in the storage unit to extract a block of program number A from the low bit rate data stream output from the demultiplexing means ,
The notification process notifies that the reserved program can be viewed through the user interface when the blocks of all the block numbers of the program number A are stored in the storage means ,
In the reproduction process, when a viewing request for the program number A that has become viewable is input from the user interface, each block of the program number A is read from the storage unit in the order of the block number at a high bit rate and supplied to the decoding / reproducing unit. A digital broadcast receiver for outputting a video / audio signal from the decoding / reproducing means .

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