JP2008099300A - Digital information transmitting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent recorded information from being transmitted to the Internet or the like against the intention of a producer to make the information hard to be utilized even if it is transmitted. <P>SOLUTION: Control information accompanying video/audio information includes information for copy restriction and information indicating whether the control information can be transmitted via a communication line such as the Internet. When recording information inhibited to be transmitted on a recording medium, the information is encrypted using a device key, a content key and the like. Even if the information is transmitted by removing the medium and attaching it to a personal computer, it becomes difficult to decrypt the information. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a recording apparatus for recording digital information such as video and audio, and in particular, a recording that restricts the redistribution and transmission of the recorded information to a third party by the authority of the copyright holder or the like. Relates to the device. Furthermore, the present invention relates to a transmission apparatus that suitably transmits digital information to such a recording apparatus. The present invention also relates to a transmission / reception apparatus that receives and preferably transmits information.

  In the field of television broadcasting and recording and reproducing devices, and in the field of package media such as movie software, digital broadcasting has started, and consumer-use digital recording and reproducing devices corresponding to this have been released. Package software for this device will appear in the near future. The advantage of digital broadcasting and digital recording devices is that there is no or very little quality degradation in the information transmission process and recording / reproduction process.

  In recent years, with the spread of the Internet, it has become easy to distribute and transfer digitized information to a large number of users. However, if many good quality copies of information are made and distributed around the copyright holder, distributed via the Internet, and repeatedly transferred, there is a problem that the profit is not returned to the copyright owner. .

  U.S. Pat. US Pat. No. 5,896,454 discloses a method of attaching 2-bit copy control information to information. This is to control the operation of the recording apparatus by selecting any one of copy prohibition, copy authorization, and copy authorization for only one generation according to the will of the copyright holder and information creator. The recording device does not perform the recording operation if the copy is prohibited, and performs the recording operation if the copy is authorized. If copying is permitted for only one generation, the recording apparatus rewrites the control information to information that does not permit further copying, and then performs a recording operation.

  Conventionally, further, in the case of copy authorization, the recording apparatus records information without encryption, and in the case of copy authorization for only one generation, the information is encrypted and recorded. This prevents information that is permitted to be copied only once for the purpose of time shifting or re-viewing, from being used for other purposes.

U.S. Pat. 5,896,454

  The matter disclosed in the above prior art provides an effective copyright protection method. However, the most disadvantageous for the copyright holder is that the information recorded on the medium is transmitted and distributed again without permission through the Internet or the like. Because it can be sent to a large number of users and can be easily transferred to a third party, the available profits are significantly less than the original, and the information is processed and unrelated to the original intention. There is a problem used for matters that are not. For this reason, it will be required that the copyright holder can not allow re-transmission on the Internet or the like even when the free copy is permitted as well as the information restricting the copy. In the above prior art, this matter is not described.

  In view of the above problems, an object of the present invention is to provide an effective solution to the problem. That is, the information recorded on the medium is prevented from being transmitted, distributed, and transferred to a large number of users using the communication means such as the Internet without knowing the copyright holder. In addition, the purpose is to make it difficult for a user to use received information even if the act is performed.

  In order to achieve the above object, in the digital information recording apparatus of the present invention, the input digital information is wired with copy control information indicating whether or not the digital information is allowed to be recorded on the recording medium and digital information. Or a re-transmission control information indicating whether or not to permit re-transmission to another apparatus using a wireless communication line, and a recording circuit for performing a predetermined process on the digital information and recording it on a recording medium, and Control detection circuit for detecting copy control information and retransmission control information from digital information, recording control circuit for controlling the recording operation of the recording circuit based on the detection result of the control detection circuit, and encryption of the digital information to be recorded And an encryption circuit.

  The recording control circuit controls the recording operation of the recording circuit according to the copy control information detected by the control detection circuit, indicates that the copy control information permits recording (Copy Free), and the retransmission control information When indicating that transmission is permitted again, the above encryption circuit is not operated, the copy control information indicates that recording is permitted (Copy Free), and the retransmission control information indicates that transmission is not permitted again. In this case, the digital information recorded by the encryption circuit is encrypted. If the copy control information indicates that only one generation is allowed to be recorded (Copy One Generation), the digital information to be recorded is encrypted by the encryption circuit regardless of the retransmission control information.

  The encryption circuit includes a first encryption circuit for encrypting digital information based on a content key generated randomly, and the content key based on a device key attached to each recording device. And a second encryption circuit for encrypting and recording the outputs of the first encryption circuit and the second encryption circuit on a recording medium.

  In the digital information transmitting apparatus of the present invention, the copy control information indicating whether or not digital information is allowed to be recorded on the recording medium and the digital information received by the receiving apparatus can be transmitted using a wired or wireless communication line. A transmission circuit that transmits the digital information including retransmission control information indicating whether or not to permit transmission again to the apparatus.

  In the digital information transmitting / receiving apparatus of the present invention, received or input digital information is retransmitted to an external apparatus using a wired or wireless communication line, and the digital information is recorded on the recording medium. Copy control information indicating whether or not recording is permitted, and retransmission control information indicating whether or not digital information is allowed to be transmitted again to another device using a wired or wireless communication line. A transmission circuit for performing predetermined processing on the digital information and retransmitting it to an external device; a control detection circuit for detecting copy control information and retransmission control information from the digital information; and encrypting the digital information to be retransmitted And an encryption circuit. When the detected retransmission control information indicates that transmission is permitted again, the digital information to be transmitted again is encrypted by the encryption circuit and transmitted again by the transmission circuit, and the detected retransmission control information is not permitted to be transmitted again. Is not transmitted again by the transmission circuit.

As described above, in the present invention, the control information sent along with the information such as video and audio uses the information of the retransmission control 106 in addition to the copy control information 104, so that the encryption at the time of recording and the Internet retransmission permission / inhibition are possible. Take control. As a result, it is possible to control copying that reflects the intention of the copyright holder and re-transmission to a communication line such as the Internet. For this reason, there is an effect that it is possible to solve the problem that a large number of high-quality copies are distributed in places where the right holder does not know.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as necessary. In the embodiment of the present invention, a new control bit is provided as necessary, but the entire system to which the present invention is applied will be described before the description.

  FIG. 1 is a block diagram showing an embodiment of the entire system used in the present invention, and shows an example in which information is transmitted / received by broadcasting and recorded / reproduced. This includes an apparatus to which the method of the present invention is applied to prevent the distribution, transfer or use of information by communication means. 1 is an information providing station such as a broadcasting station, 2 is a relay station, 3 is a receiving device, 4 is a recording / reproducing device, and 5 is a display. Here, when recording a broadcast or the like, it is recorded in the recording / reproducing apparatus 4. Further, a device using a hard disk as a recording medium, for example, may be built in the receiving device 3. In the future, video disks and video tapes can be expected to be built in as recording media. This will be described below as a case where the recording / reproducing apparatus 4 is placed inside the receiving apparatus 3. Of course, a separate recording / reproducing device may be connected to the outside of the receiving device 3.

  An information providing station 1 such as a broadcasting station transmits a signal radio wave modulated by information via a relay station 2 such as a broadcasting satellite. Of course, other transmissions such as cable transmission, telephone line transmission, and terrestrial broadcast transmission may be used. This signal radio wave received by the receiving device 3 on the receiving side is demodulated to become an information signal and recorded as a signal suitable for recording in the recording / reproducing device 4 as described later. Also, it is sent to the display 5. Here, the user can directly view the information content. Further, the information reproduced by the recording / reproducing apparatus 4 is given to the display 6 through the receiving apparatus 3, and the original information such as video / audio is viewed. When a removable recording medium in which information is recorded in advance is provided, the reproducing operation and subsequent operations in the recording / reproducing apparatus 4 to which the information is attached are performed. Information is often exchanged between devices using digital signals. For example, the receiving device 3 and the display 5 may be connected using analog signals.

  FIG. 2 is a block diagram showing an example of the configuration of the information providing station 1 such as a broadcasting station in the above system. Reference numeral 11 denotes a source generation unit, 12 denotes an encoding circuit that performs compression by the MPEG method, 13 denotes a scramble circuit, 14 denotes a modulation circuit, 15 denotes a transmission antenna, 16 denotes a management information addition circuit, and 17 denotes an input terminal.

  Information such as video and audio generated by the source generation unit 11 including a camera and a recording / reproducing device is compressed by the encoding circuit 12 so that it can be transmitted in a smaller occupied band. If necessary, the scramble circuit 13 performs transmission encryption so that only a specific viewer can view. After being modulated by the modulation circuit 14 to be a signal suitable for transmission, the signal is emitted from the transmission antenna 15 as a radio wave toward the relay station 2 such as a broadcasting satellite. At this time, the management information adding circuit 16 adds information such as the current time including the copy control information described above. Further, from the input terminal 17, for example, request information is input via a telephone line, which is omitted in FIG. This is utilized in a system for determining information to be transmitted in response to a viewer's request such as video on demand.

  In practice, a plurality of information is often multiplexed in one radio wave by a method such as time division or spread spectrum. Although not shown in FIG. 2 for simplicity, in this case, there are a plurality of systems of the source generation unit 11 and the encoding circuit 12, and a multiplex for multiplexing a plurality of information between the encoding circuit 12 and the scramble circuit 13. A circuit is placed.

  FIG. 3 is a block diagram showing an example of the configuration of the receiving device 3 in the system of FIG. Reference numeral 301 denotes an RF / IF conversion circuit, 302 a demodulation circuit, 303 an error correction circuit, 304 a descrambling circuit for canceling the transmission encryption applied to the signal, 305 a first demultiplexing circuit, and 306 an input / output terminal 307 is a second demultiplexing circuit, 308 is a decoding circuit, 309 and 310 are output terminals, 311 is a control circuit for the entire receiving apparatus 3, 312 is an information management circuit, 313 is an accounting information management circuit, 314 is a modem ( MODEM) circuit, 315 is an output terminal, 316 is an input terminal, and 317 is a command input circuit. The components 313, 314, and 315 may be removed when the charging information is not transmitted as described later. In the figure, the solid line indicates the flow of main information such as video and audio, and the dotted line indicates the flow of control signal information between the components.

  First, the flow of information such as video and audio indicated by solid lines will be described with respect to the components 301 to 310. For example, radio waves from a relay station such as a broadcasting satellite are input to the RF / IF conversion circuit 301. Here, the radio wave in the RF band is frequency-converted to an IF band (Intermediate Frequency) and becomes a signal in a certain band that does not depend on the reception channel, and the modulation operation performed for transmission by the demodulation circuit 302 is demodulated. Further, after an error in the code generated during transmission is detected and corrected by the error correction circuit 303, the descrambling circuit 304 releases the transmission cipher. Thereafter, the data is sent to the first and second demultiplexing circuits 305 and 307. As described above, particularly in the case of digital broadcasting, a plurality of pieces of information are often multiplexed on one channel by a method such as time division or spread spectrum. The demultiplexing circuit separates only desired information from this. The reason for providing the first and second and two is not only to enable so-called back program recording, but also to remove information not worth recording in the first demultiplexing circuit 305. In other words, additional information such as weather forecasts, program broadcast schedules, etc. is often included in the information, which is good to see at the time of broadcasting, but it is not worth recording and seeing at a later date. It can also be removed.

  The output of the first demultiplexing circuit 305 is given to the input / output terminal 306, and exchanges signals with the recording / reproducing apparatus 4 connected thereto. The input / output terminal 306 is a bidirectional terminal, and exchanges information to be recorded / reproduced with the recording / reproducing apparatus 4 as digital data, for example. Of course, one information line does not necessarily have to be bidirectional, and may be composed of a plurality of unidirectional or bidirectional information lines. In general, connection according to the IEEE 1394 standard is often used. The information sent from the descrambling circuit 304 or the information reproduced by the recording / reproducing apparatus 4 from the input / output terminal 306 is connected to the second demultiplexing circuit 307, and either of them is viewed. The desired information is selected and the desired information is separated. In the next decoding circuit 308, the data compression of the moving image performed before transmission is decoded and sent to the external display 5 via the output terminal 309. Two output terminals 309 and 310 may be provided, one for digital output and the other for analog output.

  Next, control signals indicated by dotted lines will be described. The control circuit 311 exchanges control signals with the components 305, 307, and 308 from the above 301, and controls the entire receiving apparatus 3 to perform a desired operation. The information management circuit 312 supplies management data when the control circuit 311 performs control in response to a request. For example, reception contract information is managed here. When the user designates a channel to be viewed, this designation is input from the input terminal 316 and sent to the control circuit 311 via the command input circuit 317. The control circuit 311 requests the reception contract information from the information management circuit 312. When it is determined that there is a contract with the channel designated by the user, a control signal is sent to each of the above-described components to instruct the receiving operation of the corresponding channel. The information management circuit 312 manages timer reservation information by the user. When it is time to reserve viewing, the control circuit 311 sends a control signal to each component described above to start a receiving operation.

  The control circuit 311 also exchanges control signals with the accounting information management circuit 313. The billing information management circuit 313 stores billing information for pay broadcasts, and this information is given to the modem circuit 314 when billing to the user occurs. Here, the information is further output to the output terminal 315 as information suitable for transmission to a communication transmission line such as a telephone line. After that, it is sent to the copyright holder, the financial institution or the information providing station 1 shown in FIG. 1 through the communication transmission path so that a prescribed amount can be obtained from the user. Of course, the communication transmission path may be wireless.

  Next, FIG. 4 is a block diagram showing a configuration example of a control information signal recorded on a recording medium by the recording / reproducing apparatus 4 of FIG. 1 in the present embodiment. This is formed by adding or rewriting information to the control information generated and transmitted by the management information adding circuit 16 of the information providing station 1 of FIG. For example, in the case of a tape medium, it is sufficient that one piece is recorded on one recording track, but it is naturally recorded in a fixed relationship with information data such as video and audio, and can be easily separated during reproduction.

  The program number 100 indicates the number of the program on the medium. The sector information 101 is a sector number obtained by dividing the program by a predetermined unit. The division may be a fixed unit, for example, a unit of 2 kbytes, or a fixed unit of information, for example, a unit for division when encoding. The number may be given in the program or may be a serial number for the entire recording medium. Information such as a recording time 107 to be described later is added in units of sectors. The time information 102 indicates how long the recorded part has passed since the start of the program. The type 103 indicates attribute information such as whether the program is sold, rented, self-made, or broadcast.

  The copy control 104 is important in the present invention and indicates whether or not the information can be recorded on the medium. Generally, Copy Never (copy prohibited), Copy One Generation (only one copy is allowed), Copy No More (copied once with Copy One Generation, no more can be copied), Copy Free ( You can copy).

  The designation of Copy Never, Copy One Generation, and Copy Free is determined by the copyright holder, such as the creator of the information, by selecting one of the three, and is given by the management information adding circuit 16 in broadcasting. There are many cases. If the information software is provided on a recording medium, the right holder records it at the time of creation. Copy No More is what was originally rewritten on the device when copying what was originally Copy One Generation. Since there are four states in total, it can be transmitted with 2-bit information. Copy Never is (1, 1), Copy One Generation is (1, 0), Copy No More is (0, 1), Copy free is (0, 0), and so on.

  Since Copy Never cannot be recorded, and Copy One Generation is rewritten and recorded as Copy No More, there are basically two states on the recording medium: Copy No More and Copy Free. Although the present applicant has proposed to record the copy prohibition information under the condition of “temporary recording”, the description is omitted here.

  The APS 105 is copy control information (APS; Analogue Protection System) for an analog recording device, and controls whether copying is possible by adding a pseudo sync pulse to an analog video signal.

  The retransmission control 106 is important in the present invention. This indicates whether or not it is permitted to transmit and transfer information again over the Internet as described above. Alternatively, in order to achieve this purpose, when information is recorded on a medium, it may indicate whether or not the information needs to be encrypted. This is also often given by the management information adding circuit 16 in broadcasting. If the information software is provided on a recording medium, the right holder records it at the time of creation.

  A description will be given of how recording on the medium is controlled by a combination of the copy control 104 and the retransmission control 106. When the copy control 104 is Copy Never, recording other than so-called temporary recording is prohibited, and in this case, the retransmission control 106 has no particular meaning. In Copy One Generation, encryption is performed at the time of recording, and information is retransmitted according to retransmission control 106. In Copy Free, it was generally interpreted that strict management was not required, and it was recorded without encryption. In the present invention, encryption is performed according to the retransmission control 106. As will be described later, it is difficult to view the contents even if re-transmission is performed if encryption is applied in addition to simply indicating that re-transmission is prohibited, and a positive blocking effect can be expected.

  As the recording time 107, for example, the time given by the management information adding circuit 16 in FIG. 2 is recorded. Recording at the recording time 107 is performed, for example, in units of sectors. The broadcast system 108 indicates a broadcast system used by the information, such as HD information (HD; High Definition) and SD information (SD; Standard Definition). The encryption 109 indicates whether or not the recorded information has been encrypted. The user identification 110 is recorded when a user-specific code is used so that information recorded on the medium can be reproduced only by the same device or the same user as when recording.

  The encrypted information 111 is used when reproducing the information recorded by encryption and decrypting the encryption. When the data amount of the information itself is large, a code number may be recorded, and the corresponding information stored in advance by the playback device may be extracted and used.

  The above is recorded at relatively fine time intervals such as every frame of video or every fixed amount of data as necessary. Of the above-described components, those indicated by 103 to 108 are often added in advance on the transmission side in the case of broadcasting. The configuration of the control information signal shown in FIG. 4 is an example, and various configurations such as the configuration, the recording position on the medium, and the frequency can be applied. Further, in the present invention, all of the contents are not essential, and some of them may be omitted. Of course, the order is not limited to this.

  The recording positions of these control signals on the medium will be described with reference to FIG. FIG. 5 schematically shows a recording position of a control information signal and information data such as video and audio on a recording medium. In the figure, (a) is suitable for a tape medium. In this case, it is desirable that the control signal block be provided for each recording track, for example. Therefore, a block of control information is arranged in the header portion or the like, for example, preceding information such as video and audio for each track. (b) is suitable for a digital video disc or the like. In this case, it is desired that there is a certain amount of information for each sector. Therefore, each sector is arranged in its header portion. (c) is suitable for a hard disk or the like. In this case, it is preferable that information such as video and audio and control information are recorded at positions distant from each other on the disc so that the entire control information can be read within a short time at startup.

  Next, the recording / reproducing operation of the recording / reproducing apparatus 4 will be described with reference to FIGS. 6 and 7, and the encryption operation according to the present invention will be described. First, the recording / reproducing apparatus 4 is suitable for recording a digitally transmitted or broadcast compressed bit stream as it is, mainly by a recent or future digital recording method. In this case, information exchange with the receiving apparatus 3 is preferably performed digitally according to the IEEE 1394 standard as described above. The recording medium is not limited to a tape, but can be a variety of media such as a removable disk such as a digital video disk and a disk built in a device such as a hard disk.

  FIG. 6 is a circuit block diagram of the recording / reproducing apparatus 4. In particular, it is suitable for a recording medium using a disk. Reference numeral 41 denotes a recording circuit, 4101 denotes a recording signal input terminal, 4102 denotes a storage means such as a semiconductor memory, 4103 denotes an encryption circuit, 4104 denotes an encryption key input terminal, 4105 denotes a recording encoding circuit, and 4106 denotes a recording medium. A recording signal output terminal, 4107 is a medium detection circuit, 4108 is a control detection circuit, 4109 is a recording control circuit, 4110 is a control signal input / output terminal, and 4111 is a control signal output terminal. 42 is a reproduction circuit, 4201 is a reproduction signal input terminal, 4202 is a reproduction / decryption circuit, 4203 is a block reproduction circuit, 4204 is a storage means such as a semiconductor memory, 4205 is an error correction circuit, 4206 is an encryption / decryption circuit, 4207 is Key input terminal for decrypting encryption, 4208 is a signal output circuit, 4209 is an output terminal for sending a reproduction signal to a receiver, 4210 is a control signal detection circuit, 4211 is a clock, 4212 is a reproduction control circuit, 4213 is a control signal The input / output terminal 4214 is a control signal output terminal.

  FIG. 7 is a block diagram showing the periphery of the recording medium of the recording / reproducing apparatus. 43 is a recording / reproducing unit, 4301 is an input terminal, 4302 is a recording amplifier, 4303 is a recording medium drive equipped with a recording medium such as a hard disk, digital video disk, and video tape, 4304 is a reproduction amplifier, 4305 is an output terminal, and 4306 is a mechanism. A control circuit and 4307 are input terminals.

  First, the operation will be described with reference to FIG. The recording circuit 41 will be described. Information to be recorded is input from the input terminal 4101. This is supplied from the input / output terminal 306 of FIG. The information after the transmission cipher is decrypted by the descramble circuit 304 is, of course, within the scope of the present invention when it is supplied without being decrypted. Note that the output from the output terminal 4209 of information reproduced by the reproduction circuit 42 described later is also given to the input / output terminal 306 in FIG. Therefore, 4101 and 4209 may be combined into one input / output terminal. Of course, this does not necessarily mean that there is only one signal line, but it may be a plurality of unidirectional or bidirectional signal lines. It may be defined by the IEEE 1394 standard.

  The input information is temporarily stored in the storage unit 4102 for each block. In addition to digital information such as video and audio, various control information as shown in FIG. In the case of broadcasting, for example, it is given by the management information giving circuit 16 of FIG. This is given to the control detection circuit 4108 to detect the control information as shown in FIG. 4 including the copy control 104 and the retransmission control 106 described above. Based on this, the recording control circuit 4109 determines whether or not this signal can be recorded, whether or not to encrypt the signal, and the result is determined by the encryption circuit 4103 and the recording encoding circuit 4105. Send to.

  On the other hand, information such as video and audio in the storage unit 4102 is encrypted in the encryption circuit 4103 according to the control signal from the recording control circuit 4109 as necessary. Encryption is performed based on information from the input terminal 4104, for example. This is a device key such as an identification number of the device, a user key such as a personal ID read by attaching an IC card held by the user to the device, or content randomly generated for each information (content) to be recorded. Keys are used.

  FIG. 9 is a circuit block diagram showing one configuration example of the encryption circuit 4103. 41031 is an input terminal, 41032 is a first encryption circuit, 41033 is a second encryption circuit, 41034 is a multiplexing circuit, 41035 is an input terminal, and 41036 is an output terminal. The input terminal 4104 is the same as that shown in FIG. The content key input from here is given to the first encryption circuit 41032 and the second encryption circuit 41033. Information to the input terminal 41031 is given from the storage means 4102 in FIG. 6, and is encrypted by the first encryption circuit 41032 based on the content key. On the other hand, the device key is given from the input terminal 41035 and sent to the second encryption circuit 41033. The content key is encrypted based on the device key by the second encryption circuit 41033. This is multiplexed with the previous information by the multiplexing circuit 41034, that is, stored in the encrypted information 111 of FIG. Therefore, the information to be recorded is supplied from the output terminal 41036 to the recording encoding circuit 4105 in FIG. 6 together with the key information. In this way, the content key can be decrypted only by a predetermined device, and the information can be decrypted and viewed, thereby preventing the use of unspecified majority.

  Further, for example, when the recorded information is played back and the viewing period is limited, it may be required to be deleted after it expires. In the present invention, the encrypted content on the recording medium is required. The purpose can be achieved only by erasing the key, and the operation can be simplified. Encryption may be performed in units of programs (contents), but in the same content, the key may be changed over time, for example, the key may be changed in units of sectors.

  According to the above embodiment, information recorded on a disk or the like may be reproduced by the device, or information recorded on a removable disk or the like may be reproduced by a disk drive of a personal computer and transmitted again via the Internet or the like. If this is contrary to the will of the copyright holder, it will be difficult for other devices or users to view.

  The encrypted information is given to the recording encoding circuit 4105. In the recording encoding circuit 4105, based on the control information from the recording control circuit 4109, when recording is prohibited, the information is blocked here, and when permitted, modulation suitable for the medium to be used is performed, and the output terminal 4106 Output to. If the copy control information is Copy Never or Copy No More, the information is blocked here. If it is Copy Free, it is modulated as it is and sent to the output terminal 4106. In the case of Copy One Generation, this copy control information is modulated by the recording encoding circuit 4105 after being rewritten as Copy No More and sent to the output terminal 4106.

  From the recording control circuit 4109 to the recording encoding circuit 4105, in addition to the copy control information, the current time of recording output from the clock 4211 is also given. If recording is possible, if necessary, This is also recorded at the same time. This is used when the recorded information is played back and a time limit is set for viewing. If the current time is included in the received information, the current time may be used, or the clock 4211 may be calibrated with the received information.

  Further, the recording encoding circuit 4105 sets the encryption information 109 of FIG. 4 to “1” when encryption is performed, for example, and “0” when it is not performed. In this way, it is possible to easily determine whether or not decryption of encryption is required when performing reproduction.

  Further, the information signal at the output terminal 4106 is given to the input terminal 4301 of the recording / reproducing unit 43 shown in FIG. This is amplified by the recording amplifier 4302 so that the laser generating element and the magnetic head can be driven, and then recorded on the recording medium as described above by the recording medium drive 4303. Reference numeral 4306 denotes a mechanism control circuit such as a motor for driving the recording medium drive 4303, which controls the recording medium with a control signal from the input terminal 4307.

  Note that the output of the recording control circuit 4109 shown in FIG. 6 is given to the output terminal 4111. If necessary, this may be given to the input terminal 4307 in FIG. 7 to instruct the mechanism control circuit 4306 to stop the recording operation when, for example, information for which recording is prohibited is input. In addition, an input / output terminal 4110 in FIG. 6 inputs and outputs control signals to and from an external device. For example, there is a method in which the control information as described above is not detected by the control detection circuit 4108 but is provided from the outside separately from data such as video and audio. It can also be shared with the input terminals 4101 and 4209 in accordance with the IEEE 1394 standard.

  Next, an operation when reproducing recorded information will be described. The information signal reproduced from the recording medium drive 4303 in FIG. 7 is amplified to a level at which the signal processing in the subsequent stage can be performed by the reproduction amplifier 4304 and then output to the output terminal 4305. A control signal from the output terminal 4214 in FIG. 6 is input to the input terminal 4307 to control the mechanism control circuit 4306. This is generated by the reproduction control circuit 4212. The recording control circuit 4109 and the reproduction control circuit 4212 are usually on the same semiconductor device. In this case, the output terminals 4111 and 4214 can be shared.

  The information signal at the output terminal 4305 in FIG. 7 is supplied to the input terminal 4201 of the reproduction circuit 42 in FIG. This is supplied to the reproduction decoding circuit 4202. Here, the modulation applied on the recording side for recording / reproducing on the medium is demodulated, the waveform is equalized, and the data is determined by the clock. Next, the block reproduction circuit 4203 detects a synchronization signal, an ID signal, etc., and the reproduction data is temporarily stored in a predetermined position of the storage means 4204 based on the detection. The error correction circuit 4205 detects a code error generated in the recording / reproducing process by a calculation operation from the stored data and corrects it to a correct value. The data after error correction is given to the encryption / decryption circuit 4206. This is for decrypting the recording encryption performed by the encryption circuit 4103 at the time of recording. Here, decryption is performed using a device key of the apparatus from the input terminal 4207, a user key such as a personal ID, or a content key. If this is not a predetermined one, normal decryption is not performed and viewing is impossible. Therefore, the recorded device or user can view it, but after the recorded medium is attached to a disk drive of a personal computer, retransmitted via the Internet, etc., and distributed to a third party, the other device Or it will be played back by the user, making it extremely difficult to view. This achieves one object of the present invention. Note that the decryption key from the input terminal 4207 may be obtained from the encryption information 111 of FIG. 4 on the recording medium or obtained by decrypting the encryption from here.

  On the other hand, the control signal detection circuit 4210 detects, for example, copy control information, recording time, and the like from the data subjected to the error correction. Next, the reproduction control circuit 4212 determines whether or not reproduction output is possible based on the detected information and the current time from the clock 4211 and controls the output of the signal output circuit 4208. Alternatively, the encryption / decryption circuit 4206 is operated or stopped. For example, if there is a time limit for the playback and viewing period and this has passed, or if it can be determined that the copy control information was recorded illegally by indicating Copy One Generation, etc., the signal output circuit From 4208, at least information that can be normally viewed is not output. If necessary, control information may be sent from the output terminal 4214 to the input terminal 4307 in FIG. 7 to stop the reproducing operation of the recording medium drive 4303 itself.

  When it is permitted to output the reproduced information, this information is given to the output terminal 4209 and supplied to the display 5 via the receiving device 3 of FIG. The data amount compression operation by MPEG or the like performed by the encoding circuit 12 of FIG. 2 is restored to the original by the decoding circuit 308 of the receiving device 3. For this reason, the user can view the information content. The decoding circuit 308 may be built in the display 5.

  Note that when copy control information or the like is different from what has been described so far, the same control may be performed using information detected from the digital watermark at the time of reproduction when the digital watermark is embedded in the video information. .

  Of course, the watch 4211 is required to have a certain degree of accuracy. Anything that can be easily changed by the user's malicious intentions will not serve the purpose. It is desirable that the time information from a broadcasting station or the like be controlled. If the time is changed intentionally, the apparatus may not be operated thereafter.

  The input / output terminal 4213 exchanges control information with an external device. For example, it is used when the reproduced information is recorded on an external recording device. The input / output terminals 4110 and 4213 can be shared. Further, for example, according to the IEEE 1394 standard, information including the input terminal 4101 and the output terminal 4209 can be transmitted / received in a single system or wirelessly using infrared rays or the like.

  A control signal given from the reproduction control circuit 4212 to the recording encoding circuit 4105 instructs, for example, erasure of information during reproduction. This is not directly related to the present invention, but there are cases where the number of reproductions is limited to one and erasure is required after reproduction. At this time, in accordance with this control signal, the recording / coding circuit 4105 generates a meaningless signal as information, and the information is erased by recording on the medium. In this case, the recording medium must be erasable. The medium detection circuit 4107 is provided for this purpose, and prevents the above-described information from being recorded on or reproduced from a medium such as a CD-R where the recorded information cannot be erased. .

  The above is the basic operation description of FIG. 6 and FIG. Here, the operation of the recording / encryption circuit 4103 in the present invention will be described in more detail. If the copy control information detected by the control detection circuit 4108 is (1, 1), that is, Copy Never, the recording control circuit 4109 sends a control signal to the recording encoding circuit 4105 to record the information on the recording medium. Stop. Of course, in this case, the encryption circuit 4103 does not need to perform an encryption operation. In other cases, several operations are possible.

  First, the first case will be described. This is a case where the retransmission control 106 is determined to function at the time of Copy Free. When (0, 0), that is, Copy Free, and the retransmission control 106 in FIG. 4 detected by the control detection circuit 4108 allows retransmission on the Internet, the encryption circuit 4103 does not perform the encryption operation. The information is transferred to the recording encoding circuit 4105. On the other hand, when the retransmission control 106 in FIG. 4 does not permit the retransmission on the Internet, the encryption circuit 4103 performs recording encryption and then passes the information to the recording encoding circuit 4105. In this case, what was recorded on the medium after performing recording encryption is decrypted on the receiving side even if the medium is removed and played back on the drive of a personal computer and transmitted to the Internet, etc. Watching is extremely difficult.

  Next, the second case will be described. This is a case where the retransmission control 106 is determined to function during Copy One Generation. If (1, 0), that is, Copy One Generation, encryption is performed by the encryption circuit 4103 regardless of the contents of the retransmission control 106, and the copy control information is (0, 1), that is, the recording encoding circuit 4105. Rewrite Copy No More and record. The retransmission control 106 is used for the control at the stage of actual retransmission.

  The third case is a case where the retransmission control 106 is determined to function during both Copy Free and Copy One Generation. Copy Free (0,0) information is handled in the same manner as in the first case, and Copy One Generation (1,0) information is handled in the same manner as in the second case. In any case, the information of the encryption 109 in FIG. 4 is, for example, “1” when recording with encryption and “0” when recording without encryption.

  It has been described so far that 2-bit copy control information and 1-bit reproduction control information are separately recorded on the recording medium. As described above, on the recording medium, the copy control information has only (0, 0) indicating Copy Free and (0, 1) indicating No More Copy. Therefore, the remaining (1, 0) and (1, 1) may be used to reduce the number of bits. For example, (0,0) allows retransmission with Copy Free, (1,0) does not allow retransmission with Copy Free, (0,1) allows retransmission with No More Copy, (1,1) Suppose that No More Copy does not allow retransmission. If re-transmission is not allowed at all for No More Copy, this should be set to (0, 1), and the above two cases should be provided only for Copy Free. In any case, the number of bits can be reduced.

  Next, another embodiment of the receiver 3 using the present invention will be described with reference to FIG. Compared with the configuration of FIG. 3, an encryption circuit 318 and a decryption circuit 319 are added to the figure, and the signal is input from, for example, an input / output terminal 306 via a modem circuit 314 and an output terminal 315 (also an input terminal here). The reproduction information of the recording / reproducing apparatus 4 can be transmitted to the Internet or the like through a telephone line or the like. Therefore, in this case, the receiving device 3 of FIG. 8 has a function as a transmitting / receiving device. The communication line may be wireless. Here, detection of control information as shown in FIG. 4 and control based thereon are performed by the control circuit 311.

  Control information such as the copy control 104 and the retransmission control 106 as described above is attached to the playback information of the recording / playback apparatus 4 input from the input / output terminal 306. The encryption applied at the time of recording has already been decrypted. Since it is reproduction information, the copy control 104 is Copy Free (0, 0) or Copy No More (0, 1).

  First, a case where the relationship between the copy control 104 and the retransmission control 106 is the above-described first case will be described. If it is Copy Free (0, 0) and the retransmission control 106 permits re-transmission over the Internet, the encryption circuit 318 sends information via the modem circuit 314 and the output terminal 315. At this time, the encryption operation may not be performed. On the other hand, when the retransmission control 106 does not recognize the retransmission on the Internet, the encryption circuit 318 stops its operation and blocks the information signal here.

  Next, a case where the relationship between the copy control 104 and the retransmission control 106 is the above-described second case will be described. When the copy control 104 is Copy No More (0, 1) and the retransmission control 106 allows re-transmission over the Internet, the encryption circuit 318 sends information via the modem circuit 314 and the output terminal 315. At this time, an encryption operation is performed. On the other hand, if the retransmission control 106 does not permit retransmission over the Internet, the encryption circuit 318 stops operating and shuts down the information signal here.

  In the third case described above, the information (0, 0) is handled in the same manner as the first case, and the information (0, 1) is handled in the same manner as the second case.

  The decoding circuit 319 in FIG. 8 is used when the receiving device 3 receives information via the Internet or the like. If the information is encrypted, it is decrypted according to a command from the control circuit 311, sent to the decoding circuit 308, and can be viewed on the external display 5. In this case, of course, a key for decrypting the encryption is required.

  The above description is about the case where the reproduction information of the recording / reproducing apparatus 4 is input from the input / output terminal 306 and is retransmitted. However, the present invention is not limited to this. The same applies to the case of retransmitting the information received from.

1 is a block diagram showing an embodiment of an entire digital information transmission / reception recording system to which the present invention is applied. The block diagram which shows an example of a structure of the information provision station 1 (transmission apparatus) in FIG. The block diagram which shows an example of a structure of the receiver 3 in FIG. The block diagram which shows an example of a structure of the control information signal in this invention. The figure which shows the recording position of the control information signal and information data on a recording medium. (A) is an example of a tape, (b) is a video disk, and (c) is an example of a hard disk. The block diagram which shows an example of a structure of the recording / reproducing apparatus 4 in FIG. The block diagram which shows the periphery of the recording medium of the recording / reproducing apparatus of FIG. The block diagram which shows an example of a structure of the receiver 3 in FIG. FIG. 9 is a block diagram showing an example of the configuration of the encryption circuit 4103 in FIGS. 6 and 8.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Information provision station (transmission apparatus) 16 ... Management information addition circuit 104 ... Copy control 106 ... Retransmission control 109 ... Encryption 110 ... User identification 111... Encryption information 2... Relay station 3... Receiver 314... Modem (MODEM) circuit 318. Decryption circuit 4 ··· Recording / reproducing device 41 ··· Recording circuit 4103 ··· Encryption circuit 41032 ··· First encryption circuit 41033 ··· Second encryption circuit 4105 ··· Recording encoding circuit 4108 ... Control detection circuit 4109 ... Recording control circuit 42 ... Reproduction circuit 4206 ... Encryption / decryption circuit 43 ... Recording / reproduction unit 5 ... display

Claims (8)

In a digital information recording apparatus for recording digital information including input video information or audio information on a recording medium,
In the digital information, copy control information indicating whether or not the digital information is allowed to be recorded on a recording medium, and the digital information is transmitted again to another apparatus using a wired or wireless communication line. Retransmission control information indicating whether or not to allow,
A recording circuit for performing a predetermined process on the digital information and recording it on a recording medium;
A control detection circuit for detecting the copy control information and the retransmission control information from the digital information;
A recording control circuit for controlling the recording operation of the recording circuit based on the detection result of the control detection circuit;
An encryption circuit for encrypting digital information to be recorded,
The recording control circuit controls the recording operation of the recording circuit according to the copy control information detected by the control detection circuit;
If the copy control information indicates that recording is permitted (Copy Free) and the detected retransmission control information indicates that transmission is permitted again, the encryption circuit is not operated,
If the copy control information indicates that recording is permitted (Copy Free) and the detected retransmission control information indicates that transmission is not permitted again, the digital information to be recorded is encrypted by the encryption circuit. A digital information recording apparatus characterized by the above. In a digital information recording apparatus for recording digital information including input video information or audio information on a recording medium,
In the digital information, copy control information indicating whether or not the digital information is allowed to be recorded on a recording medium, and the digital information is transmitted again to another apparatus using a wired or wireless communication line. Retransmission control information indicating whether or not to allow,
A recording circuit for performing a predetermined process on the digital information and recording it on a recording medium;
A control detection circuit for detecting the copy control information and the retransmission control information from the digital information;
A recording control circuit for controlling the recording operation of the recording circuit based on the detection result of the control detection circuit;
An encryption circuit for encrypting digital information to be recorded,
The recording control circuit controls the recording operation of the recording circuit according to the copy control information detected by the control detection circuit;
When the copy control information indicates that only one generation can be recorded (Copy One Generation), the digital information recorded by the encryption circuit is encrypted regardless of the detected retransmission control information. A digital information recording apparatus characterized by the above. The digital information recording apparatus according to claim 1 or 2,
The digital information recording apparatus, wherein the recording circuit records the detected retransmission control information on the recording medium. The digital information recording apparatus according to claim 1 or 2,
The encryption circuit is:
A first encryption circuit for encrypting digital information based on a randomly generated content key;
A second encryption circuit for encrypting the content key based on a device key attached to each recording device;
A digital information recording apparatus for recording outputs of the first encryption circuit and the second encryption circuit on a recording medium. The digital information recording apparatus according to claim 1 or 2,
The digital information recording apparatus, wherein the recording circuit records information on the recording medium including information indicating whether or not the digital information to be recorded is encrypted. In a digital information transmitting apparatus for transmitting digital information including video information or audio information to a receiving apparatus,
Copy control information indicating whether the digital information is allowed to be recorded on a recording medium; and
Retransmission control information indicating whether or not the receiving device allows the received digital information to be retransmitted to another device using a wired or wireless communication line;
A digital information transmission apparatus comprising a transmission circuit for transmitting the digital information included in the digital information. In a digital information transmitting / receiving apparatus that receives or inputs digital information including video information or audio information, and transmits the digital information again to an external apparatus using a wired or wireless communication line.
In the digital information, copy control information indicating whether or not the digital information is allowed to be recorded on a recording medium, and the digital information is transmitted again to another apparatus using a wired or wireless communication line. Retransmission control information indicating whether or not to allow,
A transmission circuit that performs predetermined processing on the digital information and transmits the digital information again to an external device;
A control detection circuit for detecting the copy control information and the retransmission control information from the digital information;
An encryption circuit for encrypting digital information to be transmitted again,
When the detected retransmission control information indicates that transmission is allowed again, the digital information to be transmitted again is encrypted by the encryption circuit and transmitted again by the transmission circuit, and the detected retransmission control information is permitted to be transmitted again. A digital information transmitting / receiving apparatus characterized by not transmitting again by said transmitting circuit when it indicates that there is no data. The digital information transmitting / receiving apparatus according to claim 7,
A digital information transmitting / receiving apparatus, wherein when the detected copy control information is information that allows recording (Copy Free), encryption by the encryption circuit is not performed.

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