JP2002064787A - Method and device for receiving digital signal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record digitally compressed information and to limit reproduction of the information. SOLUTION: An encrypted signal, a view right information, and guide information of a recorded program are recorded, and charging processing is conducted for each reproduction. Or a signal whose encryption is decoded, the view right information, and guide information of the recorded program are recorded, and the reproduction is permitted only for a prescribed period, based on the view right information. Since the reproduction can be limited readily and surely, unlimited reproduction and copy generation can be prevented for safeguarding the right of copyright holders and service suppliers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for receiving, recording and reproducing digital information signals such as movies and programs transmitted by transmission means such as coaxial cables, optical cables, telephone lines, and satellite broadcasts. More particularly, the present invention relates to a method and an apparatus for receiving a digital signal for limiting reproduction of a recorded digital information signal.

[0002]

2. Description of the Related Art As a method of prohibiting copying of a video signal in a recording / reproducing apparatus, for example, Japanese Patent Laid-Open No. Sho 61-288582 (hereinafter referred to as first publication) is known. The technique described in this first publication adds a signal immediately after a synchronization signal of a video signal, so that a television receiver does not malfunction and a video cassette recorder (hereinafter referred to as a VTR) has degraded image quality. The signal is recorded.

[0003] Japanese Patent Application Laid-Open No. 4-360068 (hereinafter referred to as a second publication) discloses a technique relating to a data recording / reproducing apparatus for restricting copying or preventing browsing.

As a method for digitally compressing a video signal with high efficiency, for example, MPEG-2 (Moving Picture Exper
The ITU-T Draft Rec. H.262 standard called ts Group) is known. The MPEG-2 Systems Working Standard is a transmission standard for video signals and audio signals compressed by MPEG-2.
Draft is known.

[0005]

The above standard describes a technique for compressing a program and performing digital broadcasting. When this compression method is used, a large compression ratio can be obtained.
It can broadcast eight times as many programs. For this reason, for example, a service called near video-on-demand, which repeatedly broadcasts the same 2-hour movie by shifting the time by 30 minutes, has already been started. However, since all programs cannot be broadcast all day near video on demand, it is necessary to record the broadcast signal, shift the time, and play it back at a convenient time, as before. There is.

As a method of recording and reproducing a digitally compressed and digitally broadcasted program, a method of expanding a received digital signal, converting the signal into an analog signal, and recording the analog signal on a conventional analog VTR can be considered. However, if the signal is converted into an analog signal and recorded on an analog VTR, the good S / N of the digital signal is impaired.

It is desired to digitally record a digitally broadcasted signal as it is.
A technique for recording a digital signal as compressed and transmitted as a standard has not yet been disclosed. Normally, when recording and reproducing a digital signal, there is an advantage that the same tape can be repeatedly viewed without deteriorating the image quality, since the error correction is sufficiently performed. However, on the other hand, if the same tape can be repeatedly watched without deterioration in image quality, the same thing as a cell video (sale cassette of a video recorded with a movie or the like) can be easily made and the rights of the copyright holder must be protected. Becomes difficult. The first technology to protect the rights of copyright holders in the case of conventional analog VTRs is
In the publication. In addition, the second publication discloses a technique relating to a data recording / reproducing device for restricting copying or preventing browsing.

[0008] However, the above-mentioned technology for recording a digital signal as compressed and transmitted according to the MPEG standard,
No technique is described for limiting the reproduction of a signal recorded in such a manner.

An object of the present invention is to compress, for example, the MPEG standard,
An object of the present invention is to provide a method and an apparatus capable of efficiently recording a transmitted signal and restricting reproduction.

[0010]

The following means are used to solve the above-mentioned problems. That is, a plurality of bit-compressed programs of a plurality of channels and guide information of a plurality of programs including guide information of the plurality of programs and at least information of date and time when the information is received are transmitted. And the guide information of a plurality of programs are received, one program is selected from the plurality of received programs, the selected program is recorded and reproduced by a recording / reproducing device, and the reproduced program is bit-expanded. Means for creating new guide information by selecting guide information and date and time information of a selected program from the received guide information of a plurality of programs, and Means for simultaneously outputting simple guide information to the recording / reproducing apparatus, means for setting the current time using date and time information included in the guide information of a plurality of received programs, and new reproduced Means for comparing the date information and the current time included in id information, if the comparison result is only a predetermined period and a means for inhibiting the bit extension of the reproduced program.

[0011]

The present time can be reliably set from the guide information of a plurality of received programs, and the current time cannot be artificially changed because the time is set from the received information. Also, new guide information is created from the guide information received when the selected program is recorded, and the new guide information includes the date and time information when the program was received, so that it is compared with the current time at the time of reproduction. Thus, the elapsed time at the time of reproduction can be surely known. When the elapsed time exceeds a predetermined time, the reproduction of the recording tape can be restricted by prohibiting the bit expansion.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, a video distribution service using a satellite will be described with reference to FIG. In FIG. 1, 10 is a software supplier, 20 is an operation center, 30 is a program distribution center, 31 is a transmitting device, 35
Is a current broadcasting station, 36 is a transmitting device, 40 is a satellite for distributing signals, 50 is a subscriber household, 51 is a receiving device, 52
Is a receiver decoder, 53 is a VTR, 54 is a television receiver, 55 is a telephone, and 56 is a receiving device.

The video distribution service is provided by an operator who operates the operation center 20. The operator contracts with the software supplier 10 and receives necessary software from the software supplier 10 to the program distribution center 30.
Although only one software supplier 10 is shown in the embodiment shown in FIG. 1, software is usually supplied from a plurality of software suppliers.

The program distribution center 30 launches a radio wave toward a satellite 40 by a transmitting device 31 provided in the center. Satellite 40 receives the radio wave and transmits the radio wave to subscriber 50. The transmitted radio wave is received by the receiving device 51. Although the embodiment shown in FIG. 1 shows only one subscriber 50, there are actually a plurality of subscribers.

The radio wave received by the receiver 51 is input to the receiver decoder 52, and the software of the channel selected by the receiver decoder 52 is selected. The selected software is recorded on the VTR 53 as needed. The signal recorded on the VTR 53 and reproduced at any time is transmitted to the receiver decoder 5
The video signal is restored to the original video signal and output to the television receiver 54. If the user wants to view the video as it is without recording, the video signal is restored to the original video signal without passing through the VTR 53 and then output to the television receiver 54.

[0016] The subscriber sends the desired software to the telephone 55.
It is also possible to make a request to the operation center 20 for transmission. Further, the operation center 20 can check the reception / viewing status of the subscriber 30 via the telephone line from the receiver decoder 52, and can charge for the viewing / listening status.

Further, the current broadcasting station 35 transmits the signal to the transmitting device 36.
Is received by the receiving device 56, and the received signal is input to the VTR 53 and recorded. The signal reproduced by the VTR 53 is input to the television receiver 54 and can be viewed. Of course, if it is not necessary to record on the VTR 53, the signal from the receiving device 56 is input to the television receiver 54 and can be viewed as it is.

FIG. 2 is a block diagram of the embodiment showing details of the program distribution center 30. In FIG. 2, reference numeral 100 denotes an input means of the software sent from the software supplier 10;
01 is an input means for a control signal such as a broadcast program from the operation center 20, 115 is a storage medium supply device, 16
Numerals 0 to 163 are storage media, 170 to 173 are bit compression devices, 180 is a transmission processing device, 190 is a program control device, and 191 is a program guide generating device.

The embodiment shown in FIG. 2 shows a case where the data is sent from the software supply company 10 shown in FIG. 1 by a storage medium. In this case, the terminal 100 merely indicates a receiving window of the storage medium to the program distribution center 30. The received storage medium is stored in the storage medium supply device 115 and stored under the control of the program control device 190.
Supply the storage medium. The signals reproduced by the storage media 160 to 163 are transmitted to bit compression devices 170 to 17 respectively.
3 and bit-compressed according to the MPEG-2 standard or the like, and the output signal is input to the transmission processing device 180.

A control signal such as a broadcast program is input from the operation center 20 to the program control device 190 via the input means 101. A program transmission control signal from the program control device 190 is input to the storage medium supply device 115, the storage media 160 to 163, and the transmission processing device 140. In accordance with this control signal, as described above, the storage medium in the storage medium supply device 115 is supplied to the storage media 160 to 163, and the reproduction of the software of the storage media 160 to 163 is performed.
Stop and the like are controlled.

The program distribution center 30 sends the subscription household 5
0 is distributed to the program control device 19
The information is generated by the program guide generator 191 according to the information from 0 and is input to the transmission processor 180. Transmission processing device 1
At 80, for example, signal processing for transmission according to the above-described MPEG transmission standard is performed. The transmission-processed signal is transmitted to the transmission device 3
1 and output from the transmission device 31 to the satellite 40.

FIG. 3 is a block diagram showing an example of signal processing in the transmission processing device 180. In FIG.
a, 173a, 190a, 191a are input terminals,
170b to 173b and 31a are output terminals, respectively.
184 is an encryption device, 185 is a time division multiplexing device, 1
86 is an error correction code adding device, and 187 is a modulation device.

In FIG. 3, signals from the bit compression devices 170 to 173 are input to the encryption devices 181 to 184 via input terminals 170a to 173a, respectively. Encryption device 1
At 81 to 184, each of the inputted programs is encrypted as necessary. This encryption may be performed only for the video signal, only the audio signal, or both the video signal and the audio signal. The encrypted signal is input to the time division multiplexing device 185. A terminal 190a is an input terminal for a signal from the program control device 190, and a viewing right control signal for each program is input to the time division multiplexing device 185. This signal comprises a signal indicating whether each subscriber has the right to view the broadcasted signal. Further, the program guide information from the program guide generator 191 is also input to the time division multiplexing device 185. Each signal is packetized in a predetermined format, compressed in the time axis direction, and multiplexed. In the present embodiment, the viewing right control signal and the program guide information are shown without the encryption device, but they may also be encrypted.

Further, rate control information of each program is inputted from the terminal 190a. This is because, for example, a program input from the bit compressor 170 is bit-compressed in the range of 4 to 8 Mbps, and a program input from the bit compressor 171 is 2 bits.
Information such as bit compression in a range of up to 6 Mbps. Based on this information, the time division multiplexer 185 controls the bit rates of the bit compressors 170 to 173. Output terminals 170b to 173b are output from the time division multiplexer 185.
Control signals are output to the bit compression devices 170 to 173 via the. Thus, the bit rate of each program is controlled so that the signal rate after the time division multiplexing becomes equal to or less than a certain rate.

The output signal of the time division multiplexing device 185 is input to the error correction code adding device 186. Here, for example, an error correction code for correcting a transmission error caused by noise in a satellite line, a CATV line, or the like is added. The output signal of the error correction coding device is input to the modulation device 187,
In the case of the embodiment shown in FIG. 3, the programs of the four channels are modulated into a single carrier and become one transmission channel. The signal modulated into a single carrier is output to the transmitting device 31 via the terminal 31a.

Although the embodiment shown in FIG. 2 shows an embodiment in which four storage media are provided and four programs can be input to the transmission processing device 180, more storage media are provided, and more programs are time-division multiplexed. You may.

In the embodiment shown in FIG. 2, the processing for one transmission channel is shown, but the storage media 160 to 163,
By having a plurality of combinations of the bit compression devices 170 to 173 and the transmission processing device 180, signals of a plurality of transmission channels can be transmitted.

Here, as described above, a transmission channel refers to a signal obtained by time-division multiplexing a plurality of programs and modulating it with a single carrier, and each of the plurality of programs is simply referred to as a channel.

FIG. 4 shows a specific configuration example of the receiver decoder in the subscriber household 50. In FIG. 4, reference numeral 200 denotes an input terminal of a signal from the receiving device 51, 201 denotes a signal for requesting software to an operation center,
A signal input / output terminal for exchanging a signal for knowing the reception status of a pay broadcast, 202 is a restored signal output terminal, 203 is a VTR signal input / output terminal, and 205 is the receiving device shown in FIG. The input terminal of the signal from 56, 210 is a tuner, 220 is an error correction circuit, 230 is a program division circuit, 240 is a switching circuit, 250 is an encryption / decryption circuit, 2
Reference numeral 60 denotes a decoding circuit for bit expansion, 270 denotes a signal output processing circuit, 280 denotes a control circuit, and 290 denotes an interface circuit.

Receiving device 5 that has received a signal from satellite 40
1 inputs a reception signal to the tuner 210 via the terminal 200. The tuner 210 selects the signal of the transmission channel of the program to be watched from the received signal according to the control signal from the control circuit 280, demodulates the signal modulated by the modulator 187, and outputs it to the error correction circuit 220. The error correction circuit 220 mainly corrects an error occurring in the line according to the error correction code added by the error correction code adding device 186. The error-corrected signal is input to the program division circuit 230. The program division circuit 230 selects and outputs a required program from a plurality of programs time-division multiplexed to one transmission channel by the time division multiplexing device 185 in accordance with a control signal from the control circuit 280.

The output signal of the program dividing circuit 230 is input to the switching circuit 240 and the interface circuit 290, and further to the VTR 53 via the output terminal 203. VTR
At 53, the input digital bit stream is recorded, and at the time of reproduction, the interface circuit 290 is connected via the input terminal 203 in the same form as the input bit stream.
Is input to The output signal of the interface circuit 290 is input to the switching circuit 240. Switching circuit 240
Is an interface circuit for selecting and outputting a signal from the program dividing circuit 230 when restoring a received signal according to a control signal from the control circuit 280, and for selecting and outputting a reproduction output signal of the VTR 53. 290 is selected and output.

The output signal of the switching circuit 240 is input to the encryption / decryption circuit 250. The encryption / decryption circuit 250 decrypts the signals encrypted by the encryption devices 181 to 184. The decrypted signal output from the decryption circuit 250 is input to the decryption circuit 260, which decrypts and decompresses the bit compression performed by the bit compression devices 160 to 163 shown in FIG.

The signal expanded by the decoding circuit 260 is input to the output processing circuit 270 as a component signal composed of a luminance signal and two color difference signals. Output processing circuit 27
In the case of 0, two input color difference signals are subjected to quadrature two-phase modulation and converted into carrier color signals, and the obtained carrier color signals and luminance signals are output. The output signal is input to the television receiver 54 via the output terminal 202. Because the television receiver 54 has only a composite input terminal, the output processing circuit 270
May add a luminance signal and a carrier chrominance signal to output a composite signal. Further, all of the signal including the luminance signal and the carrier chrominance signal and the composite signal may be output.

The signal from the receiving device 56 input from the input terminal 205 is recorded by the VTR 53 as necessary.
When no reproduction signal or recording is performed, an input signal or a signal equivalent to the input is output to the television receiver 54. In the embodiment shown in FIG.
, It is not always necessary to decrypt the data when recording to the VTR 53, so that the recording process can be performed free of charge at the time of recording, every time the data is reproduced.

FIG. 5 is an embodiment showing another specific example of the receiver decoder shown in FIG. FIG. 5 is partially common to the embodiment shown in FIG. 4, and the common parts are denoted by the same reference numerals and detailed description thereof will be omitted.

In the embodiment shown in FIG. 5, the switching circuit 240 is moved after the encryption / decryption circuit 250 in the embodiment shown in FIG. That is, the output signal of the decryption circuit 250 is VTR5
3 is input to the switching circuit 240, and the output signal of the VTR 53 is input to the switching circuit 240. Then, the output signal of the switching circuit 240 is input to the decoding circuit 260.

In the embodiment shown in FIG.
This is a case where a signal decrypted and decrypted with 0 is recorded. In this case, since the decrypted signal is recorded in the VTR 53, charging processing for decrypting is performed at the time of recording, and reproduction can be performed without being charged during reproduction.

Although the encryption / decryption circuit 250 is provided after the program division circuit 230 in the embodiment shown in FIG. 5, the program division processing may be performed after the encryption / decryption is performed first.

FIG. 6 is a block diagram showing an embodiment of the VTR 53. 6, reference numeral 300 denotes an input / output terminal of a signal from the receiver decoder 52 shown in FIG. 1, 302 denotes an input terminal of a signal from the receiver 56 shown in FIG. 1, 303 denotes an output terminal thereof, 305 denotes an interface circuit, and 311 denotes an interface circuit. Parity addition circuit, 312 is a modulation circuit, 320 is a tape transport system, 330 is a demodulation circuit, 331 is an error correction circuit, 340 is an analog video signal recording processing circuit, 340 is an analog video signal reproduction processing circuit, and 360 is an analog audio signal. The recording processing circuit 370 is an analog audio signal reproduction processing circuit.

The signal input from the input terminal 300 is sent to the parity adding circuit 311 via the interface circuit 305.
Is input to The parity adding circuit 311 adds a parity code for correcting an error generated in the tape transport system 320. The output signal of the parity addition circuit 311 is input to the modulation circuit 312. The modulation circuit 312 modulates the digital signal in a form suitable for the tape transport system 320. Examples of modulation schemes are NRZ, NRZI, 8
Methods such as -10 conversion, MFM, and M2 are known. The modulated signal is input to the tape transport system 320 and recorded on a magnetic tape.

At the time of reproduction, the reproduced signal is supplied to the demodulation circuit 3
The demodulation signal is inputted to the demodulation circuit 30 and demodulated corresponding to the modulation circuit 312. The output signal of the demodulation circuit 330 is an error correction circuit 331.
The error generated in the tape transport system 320 is corrected based on the parity code added by the parity adding circuit 311. The output signal of the error correction circuit 331 is input to the interface circuit 305, and the input terminal 300
After being converted into a signal of the same format as the signal input from the terminal 300, the signal is output from the terminal 300. The signal output from terminal 300 is input to receiver decoder 52 shown in FIG.

As shown in the embodiment of FIG. 6, the bit compression devices 170 to 173 shown in FIG. 2 are not required inside the VTR 53, and a digital signal recording VTR with a small circuit scale can be realized. In addition, since it is not necessary to have a bit compression device in each VTR and it is sufficient to have it in the program distribution center 30, the circuit scale becomes large and the price becomes large, but a high performance bit compression device can be used. Since the bit compression ratio can be relatively high, the data rate of the digital signal to be transmitted can be reduced. Therefore, the VTR 53 used by the subscriber can achieve high image quality, low cost, and long-time recording.

An analog signal from the receiving device 56 is input from the terminal 302 and is input to the analog video signal recording processing circuit 340 and the analog audio signal recording processing circuit 360. Here, for example, VHS standard, β standard, 8mmV
Signal processing such as TR standard is performed. The processed signal is input to the tape transport system 320. In the tape transport system 320, signals are recorded in accordance with the respective formats, similarly to the conventional VTR.

At the time of reproduction, the tape transport system 32
0 is reproduced by the analog video signal reproduction processing circuit 3
50, are input to the analog audio signal reproduction processing circuit 370, and the reproduction signal processing corresponding to the analog video signal recording processing circuit 340 and the analog audio signal recording processing circuit 360, respectively, is performed. The reproduced signal is output to an output terminal 303 as appropriate.
Is input to the television receiver 54 shown in FIG. Thus, digital broadcasting and conventional analog broadcasting can be recorded using the same tape transport system.

FIG. 7 shows the embodiment shown in FIG.
(Or output terminal 31 shown in FIG. 3).
It is a schematic diagram which shows an example of (output signal of a). The embodiment shown in FIG. 7 shows a case where four programs are transmitted on one transmission channel in accordance with the embodiment shown in FIG. Also, the case of n transmission channels (1) to (n) is shown. In FIG. 7, V1, V2, V3, and V4 are video signals of four programs, A1, A2, A3, and A4 are audio signals of four programs, PG is a signal indicating program guide information, and VECM and AECM are each This is a control signal indicating a viewing right relationship. Each of them represents a signal of one packet.

In the embodiment shown in FIG. 2, the four programs generally have different transmission rates. In addition, when viewed instantaneously, the data amount increases or decreases.
To efficiently control this, each piece of information is packetized and time-division multiplexed as shown in FIG. The details of the signal in the packet are described in the above-mentioned transmission standard. Although not shown in detail in the schematic diagram shown in FIG. 7, as described with reference to FIG. 3, the signals in each packet are encrypted by encryption devices 181 to 184 as necessary, and error correction is performed. An error correcting code in the code adding device 186,
The time division multiplexing device 185 adds header information such as a synchronization signal.

In the embodiment shown in FIG. 4 and FIG.
7 (1)... (N) are input, and the tuner 210 selects one of the transmission channel signals. Here, it is assumed that FIG. 7A has been selected.
The selected signal shown in FIG.
And is input to the program dividing circuit 230. It is assumed that the program indicated by appendix 1 is selected from the four time-division multiplexed programs in the program division circuit 230.
At this time, the program guide information PG and the viewing right control signals VECM and AECM are separately output at the same time as the video signal V1 and the audio signal A1. FIG. 8B shows the signal obtained by dividing the program. FIG.
(1) is a rewrite of FIG. 7 (1).

The switching circuit 2 in the embodiment shown in FIGS.
Reference numeral 40 first describes a case where a signal from the tuner 210 is directly selected instead of a reproduction signal of the VTR 53. FIG.
The signal obtained by dividing the program shown in (2) is transmitted to the decryption circuit 250.
Is decrypted. This is performed based on the viewing right control signals VECM and AECM signals shown in FIG. That is, if the subscribing household has the right to view the currently selected program, the encryption is decrypted. If the subscriber does not have the right to view, the decryption is not performed. Is output from the terminal 202. The output of this information is what is called an OSD, and the output processing circuit 270 adds this information to the video signal and outputs it.

The decrypted signal is input to a decryption circuit 260. The decoding circuit 260 corresponds to the bit compression devices 170 to 173 shown in FIG. 2, and decodes a signal input according to, for example, the MPEG-2 standard. The decoded signal is output from the terminal 202 via the output processing circuit 270.

In the embodiment shown in FIG. 4, the output signal of the program dividing circuit 230 is input to the VTR 53 via the interface circuit 290 and the terminal 203 in the embodiment shown in FIG. . The signal shown in FIG. 8B is input to the interface circuit 290. VTR
At 53, a signal corresponding to FIG. 8B is recorded as shown in the embodiment shown in FIG.

Next, a case where the switching circuit 240 is connected to the reproduction signal side from 53 in the embodiment shown in FIGS. The signal reproduced by the VTR 53 is reproduced according to the embodiment shown in FIG. 6, and is input to the switching circuit 240 via the terminal 203 and the interface circuit 290. This input signal is a signal substantially equal to a signal input from another input terminal of the switching circuit 240. Therefore, the output signal from the switching circuit 240 is input to the encryption / decryption circuit 250 in the case of the embodiment shown in FIG. 4, and to the decryption circuit 260 in the case of the embodiment shown in FIG. VTR53 in the same way as when restoring
Can be restored.

Next, a method for restricting the reproduction of the signal recorded by the VTR 53 will be described. Table 1 shows an example of the contents described in the program guide information PG shown in FIGS.

[0053]

[Table 1]

As shown in Table 1, the program guide information PG includes information V PID for identifying a video signal packet corresponding to a channel, and information A for identifying an audio signal packet.
Information for identifying PID and viewing right information packet VE P
The ID, the AE PID, the title of the program, the start time of the program, the completion time, and the like are described. Also, the date and time when the program guide information packet is received by the subscriber 50 are described. As shown in FIG. 2, in order to multiplex and transmit a plurality of programs on one transmission channel, it is necessary to further select a program of a desired channel from the transmission channels selected by the tuner 210. Therefore, it is necessary to add different identification information to each channel. Also, different identification information PIDs are added to identify the video signal and the audio signal as well as the program guide information and the viewing right information packet. Therefore, different identification information PIDs are added to packets of different channels in the same transmission channel, but the same packet identification information PID can exist in packets of channels between different transmission channels.

The program guide packet PG is decoded by the decoding circuit 260 and output to the TV receiver 54 via the output processing circuit 270 and the terminal 202 to select a channel of a program to be watched.

When one program is recorded on the VTR 53 and reproduced, the program recorded for the first time is not restored by selecting a channel from the program guide. If only one program is recorded, the program is left as it is. Should be regenerated. For this purpose, instead of recording the program guide information as it is at the time of recording, the program guide information is converted into program information matching the information of the program to be recorded, and the program information packet is recorded. FIG.
(3) shows an example of the recording signal in that case. In FIG. 8B, the program information packet PG is, for example, an interface circuit 290.
As shown in Table 2, recording is limited to the channel information of the program to be recorded. In FIG. 8C, the converted program information packet is represented by MPG.

[0057]

[Table 2]

FIG. 9 is a block diagram of an embodiment showing further details of the encryption / decryption circuits 250 and 260 shown in FIG. 9, reference numeral 400 denotes an input terminal of a signal from the switching circuit 240, 401 denotes an output terminal, 404 denotes an input / output terminal of a control signal with the control circuit 280, 405 denotes an input terminal of a control signal from the control circuit 280, and 410 denotes a control signal. Selection circuit,
420 is a program guide information reading circuit, 421 is a program information decoding circuit, 440 is a viewing permission determining circuit, 450 and 45.
1 is an encryption / decryption circuit, 460 is a video signal decompression circuit, 461
Is an audio signal decompression circuit, and 470 is a selection circuit.

First, a case where a signal received by tuner 210 is input will be described. A signal corresponding to FIG. Since the program information packet PG has the same packet identification information regardless of the transmission channel, the program guide information packet PG having the information shown in Table 1 is selected by the selection circuit 410 based on the packet identification information, and the program information packet PG is selected. The information is input to the information reading circuit 420. The program guide information as shown in Table 1 is input to the program guide decoding circuit 421, decodes the program guide information, and inputs to the selection circuit 470. A control signal from a control circuit 280 is input from a terminal 404 to a latitude reading circuit 420 and a selection circuit 470. When the program guide information is selected, the signal input from the program guide decoding circuit 421 is selected from the selection circuit 470 and output through the terminal 401, and further, the output processing circuit 27
0, a program guide can be viewed on the television receiver 54 via the terminal 202.

When selecting which channel of the program is to be watched while viewing the program guide information, the channel information is input from the control circuit 280 via the terminal 404 to the program guide reading circuit 420 and corresponds to the input channel. The packet identification information is read and input to the selection circuit 410. In the selection circuit 410, the video packet V1, the audio packet A1, and the viewing right information packets VECM and AECM are respectively converted into the video decompression circuit 46 according to the input packet identification information.
0, which is input to the audio decompression circuit 461 and the viewing permission determination circuit 440.

The viewing permission judging circuit 440 exchanges control signals with the control circuit 280 via the terminal 405. Based on the input viewing right information packets VECM and AECM, it is determined whether the encryption of the packets input to the encryption / decryption circuits 450 and 451 may be decrypted. If the recorded program indicates a pay program, a control signal indicating that the program is a pay program is sent to the control circuit 280 via the terminal 405. The control circuit 280 stores the amount of money corresponding to the program, and inputs a viewing permission control signal to the viewing permission determination circuit 440 via the terminal 405. The viewing permission determination circuit 440 creates information for decrypting the encryption using information from the viewing right information packets VECM and AECM as necessary, and inputs the information to the decryption circuits 450 and 451. Encryption / decryption circuit 450,
At 451, the encrypted video packet V1 and audio packet A1 are decrypted based on the input signal from the viewing permission determination circuit 440. The decrypted video packet V1 and audio packet A1 are input to the video expansion circuit 460 and the audio expansion circuit 461, respectively.

Video expansion circuit 460, audio expansion circuit 461
The video signal and the audio signal that have been bit-compressed by the above are respectively decompressed and input to the selection circuit 470. The selection circuit 470 outputs the expanded video signal and audio signal via the terminal 401 in accordance with the control signal input from the terminal 404.

Next, there is a case where a signal reproduced by the VTR 53 is inputted. In this case, a signal corresponding to 8 (3) is inputted from the terminal 400. The converted program guide information packet MPG is the program guide information packet PG before conversion.
Since the packet identification information has the same packet identification information as described above, it is input from the selection circuit 410 to the program guide reading circuit 420. Terminal 4
When the signal for selecting the program guide information is inputted from 04, the processing is performed in the same manner as when the signal is inputted from the tuner 210, and as shown in Table 2 reproduced on the VTR 53 by the television receiver 54. You can see program information.

If the program guide information is not selected from the terminal 404, the program guide reading circuit 420 selects the packet identification information of the video packet V1, audio packet A1, viewing right information packet VECM and AECM of the program being reproduced. The packets are input to the circuit 410, and the respective packets are input to the encryption / decryption circuits 450 and 451 and the viewing permission determination circuit 440. As shown in Table 2, since the converted program guide information packet has only the information of the recorded program, it is possible to input the packet identification information from the program guide reading circuit 420 to the selection circuit 410 without having to specify a channel. it can.

At the time of playback, the viewing permission determination circuit 440 determines whether or not playback is possible based on the viewing right information packets VECM and AECM, and performs a charging process if necessary. Therefore, the recorded tape cannot be reproduced without limitation, and the rights of the copyright holder and the service provider can be protected.

Next, FIG. 10 shows an embodiment of a decoding circuit corresponding to the embodiment shown in FIG. FIG. 10 is partially the same as the embodiment shown in FIG. 9, and the common parts are denoted by the same reference numerals and detailed description thereof will be omitted. 10, 430 is a time setting circuit, 431 is a comparison circuit, and 441 is a viewing permission determination circuit.

First, a case where a signal received by tuner 210 is input will be described. A signal corresponding to FIG. Since the program information packet PG has the same packet identification information regardless of the transmission channel, the program guide information packet PG having the information shown in Table 1 is selected by the selection circuit 410 based on the packet identification information, and the program information packet PG is selected. The information is input to the information reading circuit 420. From the program information reading circuit 420, date and time information when the program information packet PG is received are input to the time setting circuit 430. The time setting circuit 430 sets the current time based on the input date and time information.
Also, the program guide information as shown in Table 1 is input to the program guide decoding circuit 421, which decodes the program guide information and inputs it to the selection circuit 470. A control signal from the control circuit 280 is input via the terminal 404, and when program guide information is selected, the decoded program guide information is output from the selection circuit 470.

When a control signal for selecting a desired channel is input from the terminal 404 as in the embodiment shown in FIG. 9, packet identification information is input from the program guide reading circuit 420 to the selection circuit 410, and Are input to the video expansion circuit 460 and the audio expansion circuit 461, respectively. The bit-compressed signals are respectively decompressed, input to the selection circuit 470, and output from the terminal 400 in accordance with the control signal input from the terminal 404.

When a reproduction signal is input from the VTR 53, the converted program guide information packet MPG as shown in Table 2 is input to the program guide information reading circuit 420 as in the embodiment shown in FIG. From the middle, date and time information is input to the comparison circuit 431. The date and time information input at this time is information at the time of recording on the VTR 53. On the other hand, the current date and time are input to the comparison circuit 431 from the time setting circuit 430. Where the current date and time
The date and time when the video was recorded on the VTR 53 is compared. Also,
The viewing right information packets VECM and AECM of the reproduced program are selected and input from the selection circuit 410 to the viewing permission determining circuit 441, and the viewing permission information packets VECM and AECM are determined as to whether the program is restricted or unrestricted. Is input to the comparison circuit 431. The comparison circuit 431 does not output a control signal for restricting decompression to the video decompression circuit 460 and the audio decompression circuit 461 in the case of a program having no reproduction restriction. In the case of a program having a reproduction restriction, the condition is input to the comparison circuit 431. The reproduction restriction condition is, for example, only on the day of recording, 3 days after recording.
Reproduction is permitted with a time limit such as days or one week of viewing. According to this condition, the comparison circuit 43
By taking the difference between the current date and time and the recorded date and time compared in step 1, it is determined whether or not reproduction is possible. Depending on whether this playback is possible,
If reproduction is impossible, a signal for restricting expansion is input to the video expansion circuit 460 and the audio expansion circuit 461. This allows
It is no longer possible to play the recorded tape indefinitely, and the rights of the copyright holder and the service provider can be protected.

According to the present invention, for example, even if a recorded tape is duplicated, only a tape having the same conditions can be reproduced. You can't, and you can't make pirated tapes.

Since the current time is set in accordance with the received signal, the current time does not shift and the current time cannot be artificially shifted. Further, for the same reason, the elapsed time after the recording can be accurately and indicated, and cannot be changed artificially, so that the above right can be surely protected.

[0072]

According to the present invention, input digital information can be recorded efficiently, and reproduction can be restricted simply and reliably.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a digital broadcasting and analog broadcasting system according to the present invention.

FIG. 2 is a block diagram showing one embodiment of a program distribution center according to the present invention.

FIG. 3 is a block diagram showing one embodiment of a transmission processing device according to the present invention.

FIG. 4 is a block diagram showing one embodiment of a receiver decoder according to the present invention.

FIG. 5 is a block diagram showing one embodiment of a receiver decoder according to the present invention.

FIG. 6 is a block diagram showing one embodiment of a VTR according to the present invention.

FIG. 7 is a waveform diagram of a signal according to the present invention.

FIG. 8 is a waveform diagram of a signal according to the present invention.

FIG. 9 is a block diagram showing one embodiment of the present invention.

FIG. 10 is a block diagram showing one embodiment of the present invention.

[Explanation of symbols]

 52 receiver decoder 53 VTR 171 to 173 bit compression device 180 transmission processing device 181 to 184 encryption device 185 time division multiplexing device 186 error correction code adding device 187 modulation device 220, 331 error correction Circuit 230 ... Program division circuit 250 ... Encryption / decryption circuit 260 ... Decryption circuit 311 ... Parity addition circuit 410,470 ... Selection circuit 420 ... Program guide reading circuit 430 ... Time setting circuit 431 ... Comparing circuit 440,441 ... Viewing permission judgment circuit

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H04N 5/92 H04N 5/92 H 5D110 7/025 7/08 A 7/03 5/782 Z 7/035 7/16 (72) Inventor Kyoichi Hosokawa 1410 Inada, Hitachinaka-shi, Ibaraki Prefecture Personal Media Equipment Division, Hitachi, Ltd. (72) Inventor Keiji Noguchi 1410 Inada, Hitachinaka-shi, Ibaraki Prefecture Personal Media Equipment Division, Hitachi, Ltd. ) 5C018 HA09 5C053 FA13 FA22 GA11 GB05 GB15 GB38 JA21 JA22 KA08 KA24 KA26 LA06 LA07 5C063 AB03 AB07 CA23 DA01 DA05 DA07 DA20 5C064 BA07 BB02 BB10 BC04 BC06 BC10 BC17 BC18 BC20 BC22 BC23 BC25 BD02 BC08 BD09 DE04 CC04 GK08 GK10 GK12 GK17 HH15 HL11 JJ07 5D110 AA04 AA27 AA29 BB16 DA06 DA11 DA17 DB09 DC16 DE01 FA08

Claims (4)

[Claims] 1. Transmitting a plurality of bit-compressed programs of a plurality of channels and guide information of the plurality of programs, receiving the transmitted plurality of programs and guide information of the plurality of programs, In a system in which one program is selected from a plurality of programs, the selected program is recorded and reproduced by a recording / reproducing device, and the reproduced program is bit-expanded, restored, and watched. Selecting the guide information of the selected program from the guide information of the program to create new guide information; outputting the selected program and the new guide information to the recording / reproducing device simultaneously; A digital signal receiving method, characterized in that the reproduced program is bit-expanded and restored on the basis of new guide information reproduced from the computer. 2. The method according to claim 1, wherein at least two of the plurality of programs and guide information of the plurality of programs are packetized, time-division multiplexed and transmitted, and the guide information includes at least identification information of each packet. Receiving a digital signal, wherein packet identification information is read from the reproduced new guide information, and a packet of the reproduced program is selected and bit-extended based on the read packet information. Method. 3. The guide information of a plurality of programs according to claim 1, including information on the date and time at which the guide information of the plurality of programs is received, and information on the date and time included in the guide information of the received programs. The new guide information includes the date and time information included in the received guide information of the plurality of programs, and the date and time information included in the reproduced new guide information and the current time. A digital signal receiving method comprising comparing times and prohibiting bit expansion of the reproduced program when the result of the comparison exceeds a predetermined period. 4. A plurality of bit-compressed programs of a plurality of channels and guide information of the plurality of programs including guide information of the plurality of programs and at least information on the date and time when the information is received are transmitted. Receiving the transmitted plurality of programs and the guide information of the plurality of programs, selecting one program from the plurality of received programs, recording and reproducing the selected program with a recording / reproducing device, In a system in which a reproduced program is bit-expanded, restored, and viewed, a new guide information is created by selecting the guide information of the selected program and the information of the date and time from the guide information of the plurality of received programs. Means for simultaneously outputting the selected program and the new guide information to the recording / reproducing apparatus; and the current time using the date and time information included in the received guide information of the plurality of programs. Means for setting the time; means for comparing the current time with the date and time information included in the reproduced new guide information; and bits of the reproduced program if the comparison result exceeds a predetermined period. A digital signal receiving device comprising means for inhibiting decompression.