JP2011096358A - Copy control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve usability while performing copy control when a digital broadcast program permitting one-generation recording (Copy One Generation) is recorded. <P>SOLUTION: There is provided a control method in a receiver which receives digital contents and copy control information of the digital contents. If a recording medium does not adapt to managing limit of the number of copies, when the received copy control information indicates copy generation information to permit one-generation copying, the digital contents are recorded in a copy-inhibited state. If the recording medium adapts to managing the limit of the number of copies, when the received copy control information indicates inhibition of a plurality of copies, the digital contents are recorded in a copy-inhibited state. When the received copy control information indicates permission of the plurality of copies, the digital contents are recorded in a copyable state until the predetermined copyable number. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The technical field relates to content copy control.

  Regarding the above technical field, Patent Document 1 states that “use of information when copying one generation (Copy One Generation) is rewritten to information prohibiting further copying (Copy No More) and recorded. As a means to solve the problem, “Copy one generation is allowed within a predetermined time after recording (Copy One Generation). In addition, it is described that two identical streams are recorded on the medium, one is used for normal viewing, and the other is moved to another medium and stored as necessary. .

JP 2002-319227 A

  In recent years, recording apparatuses capable of recording digital broadcasts have become widespread with the expansion of digital broadcast services.

  When recording a digital broadcast, the received digital broadcast is recorded on an HDD (hard disk drive) built in the recording device, and the digital broadcast program is recorded from the HDD to another recording medium (for example, an optical disk, a semiconductor memory, or another HDD). Copy is permitted when Copy is Free (Copy Free), and digital broadcast programs are permitted to be recorded for one generation (meaning that copying of copies (two or more copies) is not permitted, Copy One Generation) is Move. (Moved).

  In the recording apparatus of Patent Document 1, even when the digital broadcast program is Copy One Generation, copying can be performed within a specified time, so that it is possible to compensate for the interruption of recording.

  However, in the recording apparatus of Patent Document 1, copying is not allowed as in the conventional case if the specified time has passed. For example, in a recording device that cannot simultaneously record a program to the HDD and copy from the HDD to the optical disk, if the program to be recorded is embedded and access to the HDD is concentrated, the copying from the HDD to the optical disk is completed. It is conceivable that the specified time will pass while you cannot.

  In view of this, an apparatus or method for improving usability while performing copy control in the case of recording a digital broadcast program permitting one-generation recording (Copy One Generation) is provided.

  Specifically, for example, in the control method in the receiving apparatus that has received the digital content and the copy control information of the digital content, the recording is performed when the received copy control information indicates copy generation information that permits one generation of copying. If the medium is a recording medium that does not support copy number limit management, digital content copying is prohibited and recorded, and if the recording medium is a recording medium that supports copy number limit management When the received copy control information indicates whether or not multiple copies are made, copying of digital contents is prohibited and recorded, and when the received copy control information indicates that multiple copies are possible The digital content is recorded in a copyable state up to a predetermined copyable number.

  According to the above means, in the case of recording a digital broadcast program for which one generation recording is permitted (Copy One Generation), it is possible to improve the usability of the recorded content while performing copy control.

It is a block diagram which shows the structural example of a system. 3 is a block diagram illustrating a configuration example of a transmission device 1. FIG. It is an example of the structure of the content use descriptor which is one of copy control information. This is a description example for each field of the content usage descriptor. It is an example of the structure of the digital copy control descriptor which is one of copy control information. It is an example of the information which controls a copy generation. It is an example of the reception process in the receiver 3 of each field of the content use descriptor sent from the transmitter 1. This is an operation example of protection of program content by using the copy control information by the transmission apparatus 1. This is an example of control when the receiving device 3 stores (records) program content using copy control information. 3 is a block diagram illustrating an example of a configuration of a receiving device 3. FIG. It is a figure which shows the example of the transport packet which added the time stamp. It is a figure which shows the example which recorded the program content on the recording medium. The copy of one generation is a flowchart showing an example of a procedure for creating copy information of management information and the number of copies when permitted program contents are recorded. It is a flowchart which shows the example of the procedure which copies program content. It is a flowchart which shows the example of the procedure of moving (moving) program content. The figure which shows an example of the recording medium which can manage several copies. The copy of one generation is a flowchart showing an example of a procedure for creating copy information of management information and the number of copies when permitted program contents are recorded.

  Hereinafter, examples (examples) of the preferred embodiments of the present invention will be described. However, the present invention is not limited to this embodiment. The present embodiment mainly relates to handling of information that is permitted to be copied by one generation.

<System>
FIG. 1 is a block diagram illustrating a configuration example of a system according to the present embodiment. The case where information is transmitted / received by broadcast and recorded / reproduced is illustrated.

  1 is a transmitter installed in an information providing station such as a broadcast station, 2 is a relay device installed in a relay station or a broadcasting satellite, 3 is a receiver installed in a user's house, and 10 is a receiver 3 This is a reception recording / reproducing unit built in. The reception recording / reproducing unit 10 can record and reproduce the broadcast information.

  The transmission device 1 transmits the modulated signal radio wave via the relay device 2. For example, transmission by cable, transmission by telephone line, transmission by terrestrial broadcasting, etc. can be used. As will be described later, the signal radio wave received by the receiving device 3 is demodulated into an information signal, and then recorded as a signal suitable for recording as necessary. Further, the user can view the video and audio indicated by the information signal by connecting the receiving device 3 to a display (not shown) when the receiving device 3 has a built-in display, or connecting the receiving device 3 to a display (not shown). Can do.

<Transmitter>
FIG. 2 is a block diagram illustrating a configuration example of the transmission device 1 in the system of FIG.

  Reference numeral 11 denotes a source generation unit, 12 denotes an encoding unit that performs compression by the MPEG method, 13 denotes a scramble unit, 14 denotes a modulation unit, 15 denotes a transmission antenna, and 16 denotes a management information addition unit. Information such as video and audio generated by the source generation unit 11 including a camera and a recording / playback device is compressed by the encoding unit 12 so that it can be transmitted in a smaller occupied band. If necessary, the scrambler 13 performs transmission encryption so that a specific viewer can view. After modulation to be a signal suitable for transmission by the modulation unit 14, the signal is transmitted from the transmission antenna 15 to the relay device 2 as a radio wave. At this time, the management information adding unit 16 adds information such as copy control information and current time, which is information for controlling copying.

  In many cases, a plurality of pieces of information are 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 unit 12, and a multiplex for multiplexing a plurality of pieces of information between the encoding unit 12 and the scramble unit 13. Part (multiplexing part) is placed.

<Copy control information>
The copy control information is information for controlling restrictions such as whether or not copying is allowed and the number of times of copying, and is added by the management information adding unit 16, for example. Includes content usage descriptor and digital copy control descriptor.

  FIG. 8 shows an example of operation related to protection of program content by using copy control information.

  “Operation possible” indicates that the transmission side can select a generation restriction using digital copy control information for content corresponding to each service form. For example, “pay-per-view” indicates that any digital copy control information may be used. On the other hand, “pay-per-view pay broadcasting” indicates “copy prohibited” on the transmission side. Indicates that it cannot be selected.

  “Flat / Tier” refers to contracting a plurality of channels together for pay broadcasting or the like as a flat contract, and contracting for each channel as a tier contract.

  “Other than the above” includes, for example, “in the case of a program that is not a pay broadcast and does not involve content protection”.

  FIG. 3 shows an example of the structure of a content usage descriptor that is one piece of copy control information. The content usage descriptor is generated and added by, for example, the management information adding unit 16, and stored in PSI (Program Specific Information) (eg, PMT (Program Map Table)) or SI (Service Information) of MPEG-TS and transmitted. Information.

  The usage of the content usage descriptor is arranged (transmitted) when describing control information related to storage (recording) and output for the program. This means that if the 1-bit field of digital_recording_control_mode (digital copy mode bit) is “1”, even if the digital_recording_control_data of the digital copy control descriptor described in FIG. This indicates that recording is possible as "Copyable". In the case of “0”, it cannot be recorded as “Number Limited Copy Allowed”.

  The content usage descriptor is always arranged (sent) when the program is a target of output protection. This output protection means that protection is performed for the high-speed digital interface output of the content that can be copied without restriction using the output protection bit (encryption_mode) of the content usage descriptor. In other words, although it is encrypted when output via a digital interface or when copying to a recording medium, it does not limit the number of copies or generations. Retransmission to the Internet is virtually impossible. Also called “copy free with output protection” or EPN (encryption plus non-assertion).

Further, it is always arranged (sent) when the digital copy control information of the program is “one-generation copy is permitted” and is not a target of “number-limited copy is permitted”.

  FIG. 4 shows an example of the description contents of each field of the content usage descriptor.

  In “descriptor_tag”, “0xDE” indicating a content use descriptor is described. In “descriptor_length”, the descriptor length of the content use descriptor is described. In “digital_recording_control_mode”, “0” is described when the digital copy control information is “one generation copy is permitted” and is not a target of “number limited copy is possible”. If the digital copy control information is “one-generation copy is permitted” and the target is “number-limited copy is permitted”, “1” is described.

  In “encryption_mode”, “0” is described when the digital copy control information is “copying possible without restriction” and the high-speed digital interface output is protected.

  “Retention_mode” means temporary storage control bit, and “0” is written to indicate that temporary storage is possible even if “digital_recording_control_data” (digital copy control information) in the digital copy control descriptor is “copy prohibited” To do. “Retention_state” means a temporary storage allowable time, and describes “111” indicating that storage for 1 hour 30 minutes is possible. Note that “image_constraint_token”, “retention_state”, and “encryption_mode” are “1” in the default state.

  Each field will be described later with reference to FIG.

  FIG. 5 shows an example of the structure of a digital copy control descriptor that is one piece of copy control information. The digital copy control descriptor is information that is generated and added by, for example, the management information adding unit 16 and stored and transmitted in MPEG-TS PSI (such as PMT) or SI.

  The digital copy control descriptor represents information for controlling the copy generation by a 2-bit field of “digital_recording_control_data” (digital copy control information).

  FIG. 6 shows an example of digital copy control information. When the digital copy control information is “00”, it indicates that copying is possible without restriction, when it is “01”, it indicates that it is defined by the broadcaster, and when it is “10”, it is one generation copy. “11” indicates that copying is prohibited. Note that “1st generation copying is possible” means that the received broadcast signal can be recorded (first generation copy), but the broadcast signal cannot be copied (copied) after recording.

  The content use descriptors in FIGS. 3 and 4 are also called copy number restriction information, and the digital copy control information in FIGS. 5 and 6 is also called copy generation restriction information.

<Receiving device>
FIG. 10 is a block diagram illustrating a configuration example of the receiving device 3 in the system of FIG. In FIG. 10, it is assumed that a place where lines representing flows of information, PCR and the like intersect is not in contact. However, the portion marked with a black circle is in contact and indicates that it has branched from there.

  The receiving device 3 is a receiving device that receives a digital broadcast or an IP (Internet Protocol) broadcast via a network, and performs recording and reproduction. A case will be described in which a signal encoded by the Moving Picture Experts Group (MPEG) system and multiplexed by the MPEG2-TS system is handled as an image compression technique.

  The receiving device 3 includes a reception recording / reproducing unit 10, a control unit 114 (for example, a CPU (Central Processing Unit)), and a user interface unit 115 (for example, a keyboard, a mouse, or a remote controller as an input device).

  In this configuration example, each is described as a hardware element, but a part may be realized by software. Further, the present invention may be applied to transmission and reception of video content, audio content, and the like to a specific user such as VOD (Video On Demand) via a network. These are collectively called distribution.

  The control unit 114 is connected to each unit (including the reception recording / reproducing unit 10) of the reception device via a bus unit, and controls the operation of the entire reception device. In addition, various processing signals are received by receiving various command signals from the user via the remote control of the user interface unit 115 and controlling each unit connected via the bus unit based on the command signals.

  The reception recording / reproducing unit 10 includes a tuner decoding unit 101, a selector 102, a separation / extraction unit 103 (for example, a demultiplexer), an input buffer 104, a decoding unit 105 (for example, an MPEG decoder), a network interface unit 106, and a buffer management unit 107. , Clock reproduction unit 108, time stamp comparison / output unit 109, time stamp addition unit 110, reading unit 111, writing unit 112, built-in recording medium 113, output unit 116, fixed clock generation unit 117 (for example, crystal oscillator), content A management information creation unit 119 and a content management information analysis unit 120 are included.

  The built-in recording medium 113 (also referred to as a first recording medium) and the removable recording medium 118 (also referred to as a second recording medium) are random accesses such as a hard disk drive (HDD), a semiconductor memory, a magnetic disk, an optical disk, and a magneto-optical disk. Is a possible medium.

  The output unit 116 is a display unit using a CRT (Cathode Ray Tube), an LCD (Liquid Crystal Display), a PDP (Plasma DISPLAY Panel), an audio output unit such as a speaker, or other analog or digital display devices. An HDMI (High Definition Multimedia Interface) output terminal for outputting video data / audio data. The output unit 116 reproduces the decoded video / audio on the display unit / audio output unit which is an output device. Alternatively, video / audio content data or the like is output to another display device or the like via an output terminal (for example, HDMI).

  The tuner decoding unit 101 receives a digital broadcast signal transmitted from the transmission device 1 via a broadcast transmission network such as a radio (satellite, terrestrial) or cable. Channel selection and detection processing are performed on the frequency of a physical or virtual channel designated via a user operation unit such as a remote controller of the user interface unit 115 and the control unit 114. Also, the MPEG2-TS (transport stream) after digital demodulation and error correction processing is output to the selector 102.

  The selector 102 performs a 3-input 1-output selection process in accordance with control from the control unit 114, and outputs the output to the separation / extraction unit 103.

  The separation / extraction unit 103 separates / extracts the transport packet of the channel (program) designated via the user operation unit such as a remote controller of the user interface unit 115 and the control unit 114 from the input MPEG2-TS, The separated / extracted transport packet is output to time stamp adding section 110. Also, the separation / extraction unit 103 is a video and audio PES (Packetized Elementary Stream) from a transport packet of a channel (program) designated via a user operation unit such as a remote controller of the user interface unit 115 and the control unit 114. Alternatively, ES (Elementary Stream) is separated and extracted and output to the input buffer 104.

  The ES is compressed / encoded image / audio data, and the PES is a packet obtained by dividing the image ES or audio ES into appropriate sizes. Further, the separation / extraction unit 103 extracts a PCR (Program Clock Reference) from a transport packet of a channel (program) designated via the user operation unit such as a remote controller of the user interface unit 115 and the control unit 114, The data is output to the clock reproduction unit 108.

  The separation / extraction unit 103 records on a built-in recording medium 113 or a removable recording medium 118 from a transport packet of a channel (program) designated via a user operation unit such as a remote controller of the user interface unit 115 and the control unit 114. Channel title (program) title, start / end date / time of the program, copy generation control information and information indicating whether or not multiple copies are possible are detected, and an encryption key for the data is created, and the contents management information creation unit 119 is sent. Output. The title, the start / end date / time of the program, the copy generation control information and the information indicating whether or not a plurality of copies can be made are stored in, for example, MPEG-TS PSI or SI information and transmitted from the transmission apparatus 1.

  The input buffer 104 temporarily stores the video / audio PES or ES from the separation / extraction unit 103. The decoding unit 105 compares the DTS (Decoding Time Stamp) / PTS (Presentation Time Stamp) corresponding to the PES or ES stored in the input buffer 104 with the STC (System Time Clock) count value from the clock reproduction unit 108. By taking the decoding / display timing, the video / audio PES or ES stored in the input buffer 104 is extracted and decoded, and the decoded video / audio is output to the output unit 116.

  The buffer management unit 107 monitors the amount of unprocessed transport packets by the decoding unit 105 in the input buffer 104, and controls the reading start and stop of the reading unit 111 according to the amount.

  The clock recovery unit 108 uses PCR to reproduce, for example, the system clock of the receiver whose frequency matches the system clock of the encoding / multiplexing unit (not shown) on the transmitting apparatus 1 side. The reproduced system clock is output to the STC counter in the clock recovery unit 108, the time stamp addition unit 110, and the like. In addition, the STC count value of the STC counter that operates based on the reproduced system clock is output to the decoding unit 105.

  The time stamp adding unit 110 generates a time stamp by a counter that operates based on, for example, a system clock reproduced by the clock reproducing unit 108 or a crystal oscillator (not shown), and is separated and extracted by the separation / extraction unit 103. A time stamp is added to each transport packet and output to the writing unit 112.

  FIG. 11 shows an example of the structure of a transport packet to which a time stamp is added. A transport packet (TSP) with a length of 188 bytes according to the MPEG standard has a 4-byte time stamp (for example, the time when the receiver receives the transport packet) added to the beginning, and a packet with a length of 192 bytes Become. The time stamp holds time stamp information when the transport packet arrives. The MPEG standard TS is composed of a header of the first 4 bytes, followed by a payload of 184 bytes (or an adaptation field).

  A content management information creation unit (content information creation unit) 119 includes a title from the separation / extraction unit 103, a start / end date / time of a program, copy generation control information and copy number control information (indicating whether multiple copies are possible), Management information is created based on the key information and output to the writing unit 112. The copy generation control information and the copy number control information may be received from the transmitter 1 as the content use descriptor and the digital copy control descriptor described with reference to FIGS. May be created as new information.

  The writing unit 112 performs an encryption process on the management information created by the content management information creating unit 119 and the transport packet with the time stamp added by the time stamp adding unit 110 based on the key information in the management information. The encrypted data subjected to the processing is recorded on the built-in recording medium 113 or the removable recording medium 118. As a result, the transport packet to which a plurality of time stamps including video / audio data of a certain channel (in other words, a certain program content and downloaded content) is added is subjected to encryption processing. One stream having encrypted data is stored in the internal recording medium 113 or the removable recording medium 118 as one data file or two or more fragment data files obtained by dividing the data file.

  The time stamp can also be said to be time information related to the temporal position of the transport packet to which the stamp is attached. For example, the time when the transport packet from the separation / extraction unit 103 is input to the time stamp adding unit 110, or a certain transport packet (for example, the immediately preceding or first transport packet) It can also be said that this is a time difference. As described above, this time stamp is different from a time stamp (for example, PCR, DTS, or PTS) included in advance in the transport packet.

  FIG. 12 shows an example in which program content is recorded on the internal recording medium 113 or the removable recording medium 118.

  For each program content, management information indicating the contents of the program content and data (video / audio) that is the substance of the program content are recorded in the management information area 501 and the data area 502, respectively. The management information includes, for example, a file number 503 indicating the title of the program content, a date 504 indicating the start / end date and time of the program, a data area start address and recording size 505, copy information 507, copy number 508, key information 506, and the like. Record. In the data area 502, program contents are written from an address corresponding to the head address 505 recorded in the management information area 501. Each time program content is newly recorded, file number 1, file number 2,..., File number n, management information, and program content are sequentially recorded.

The copy information 507 is copy generation control information included in the management information created by the content management information creation unit 119. For example, the copy information 507 is a 2-bit signal,
00 = Copy Free
10 = Allow one generation of recording (Copy One Generation)
11 = Copy Never
Such a designation is conceivable. In this case, it is defined that the program content recorded with “Copy One Generation” in the receiving device 3 cannot be copied any more than 01 = Copy One Generation (No More Copies). The designation method may be the same operation as that of the digital copy control information described with reference to FIG.

  The copy number 508 is copy number control information included in the management information created by the content management information creation unit 119. The number of copies 508 is information created by the content management information creation unit 119 based on the copy generation control information received from the separation / extraction unit 103 and information indicating whether or not multiple copies are possible. If the copy generation control information permits one-generation recording (Copy One Generation) and the information indicating whether or not multiple copies are possible is “possible”, the program content is recorded as “No More Copies”, and the same or different recording medium Then, information indicating the permitted number of copies for enabling copying in the same or different format is stored, and for example, “8” indicating the meaning of permitting eight copies is input. This numerical value should conform to a standard or the like. On the other hand, if the copy generation control information permits one-generation recording (Copy One Generation) and the information indicating whether or not multiple copies are possible is “No”, the program content is recorded as “No More Copies”, indicating that copying is not possible. "0" (indicating that copying is not permitted) is input as information indicating the permitted number of copies for copying.

  Note that the copy generation that is stored in the PSI or SI of the MPEG-TS and transmitted from the transmission apparatus 1 is the actual data of the program content in which the program content of “Copy One Generation” is recorded as “No More Copies”. The control information and information indicating whether or not multiple copies are possible are not changed.

  The copy information 507, the copy number 508, and the key information 506 are encrypted, for example, so as not to be tampered with.

  Returning to the description of FIG. 10, the content management information analysis unit 120 reads the management information stored in the internal recording medium 113 or the removable recording medium 118 via the reading unit 111, analyzes the content of the management information, and When reproducing, copying, or moving the program content stored in the recording medium 113 or the removable recording medium 118, the program content can be selected via the user operation unit such as a remote controller of the user interface unit 115 and the control unit 114. The title of the program content, the start / end date / time of the program, the copy information, the number of copies, and the like are passed to the control unit 114 so that they can be performed. Also, key information for decrypting the encrypted data is passed to the reading unit 111.

  The reading unit 111 is controlled via the buffer management unit 107 or the control unit 114, reads management information from the built-in recording medium 113 or the removable recording medium 118, outputs the management information to the content management information analysis unit 120, and incorporates encrypted data A transport packet, which is read one after another from the recording medium 113 or the removable recording medium 118, and appended with a time stamp obtained by decrypting the encrypted data based on the key information passed from the content management information analysis unit 120, The data is output to the time stamp comparison / output unit 109.

  The time stamp comparison / output unit 109 includes a counter value of a counter that operates based on a fixed clock recovery unit 117 such as a crystal oscillator, and a time stamp of a transport packet to which the time stamp read by the reading unit 111 is added. If they match, the time stamp is deleted (removed) from the transport packet and output to the selector 102 and the network interface unit 106. As described above, when the remaining amount of the input buffer 104 is monitored by the buffer management unit 107 and the reading unit 111 is controlled according to the amount, the transport is performed without comparing the counter value with the time stamp. The time stamp may be deleted from the packet and output to the selector 102 and the network interface unit 106. In particular, it is preferable to output by this method at the time of reproduction other than normal reproduction (single speed reproduction).

  The network interface unit 106 is connected to another device (recorder, display, personal computer, or server outside the home) that is the output destination / input source via a line (IEEE1394 cable, LAN cable, wireless, etc.). Connected. The time stamp comparison / output unit 109 receives a transport packet such as video / audio from which the time stamp has been deleted, and converts the transport packet into a format according to each transmission standard via a line. Output to another device that is the output destination. Also, data such as video / audio is input from another device as an input source via a line in a format according to each transmission standard, converted into a transport packet, and output to the selector 102. Note that there may be a plurality of network interface units 106.

<Reception and recording processing related to copy control information>
A detailed example of processing of the receiving apparatus 3 related to the copy control information described with reference to FIGS. 3 to 6 sent from the transmitting apparatus 1 will be described.

  FIG. 7 shows an example of processing for each field of the content usage descriptor in the receiving apparatus 3.

  If “descriptor_tag” is “0xDE”, it is determined that the descriptor is a content use descriptor. Based on “descriptor_length”, it is determined as the descriptor length of the content use descriptor. If “digital_recording_control_mode” is “1”, if the digital copy control information is “one-generation copy is permitted”, it is determined that the number of copies is permitted. If it is “0”, if the digital copy control information is “one-generation copy is permitted”, it is determined that the number of copies is not permitted. With regard to “image_constraint_token”, it is determined that the resolution of the video signal output is not limited no matter what value is entered. Regarding “retention_mode”, it is determined that temporary storage is possible regardless of any value. Regarding “retention_state”, it is determined that the temporary storage allowable time is 1 hour 30 minutes regardless of any value. If “encryption_mode” is “1”, it is determined that the high-speed digital interface output is not protected when the digital copy control information is “Copyable without constraint”. If it is “0”, if the digital copy control information is “copying possible without restriction”, it is determined that the high-speed digital interface output is protected.

  In addition, when a content utilization descriptor is not arrange | positioned (sent) for some reason, it is good to interpret each field as the following values. digital_recording_control_mode = '1', image_constraint_token = '1', retention_mode = '0', retention_state = '111', encryption_mode = '1'.

  FIG. 9 shows an example of control in which the receiving device 3 stores (records) program content using copy control information.

  For example, when program content is stored, if digital_recording_control_data of the digital copy control descriptor is “10” and “one-generation copying is possible”, the content shown in FIG. Accumulate as "copy prohibited". However, when digital_recording_control_mode is “1”, it is stored as “number limited copy allowed”. Even when accumulation is performed with “recopy prohibited”, the value of digital_recording_control_data in the digital copy control descriptor does not need to be changed.

  If digital_recording_control_data of the digital copy control descriptor is “10” and “one-generation copying is possible”, a plurality of copies must not be generated. However, storage in areas where the user cannot access for backup purposes is excluded. In addition, the above restriction is imposed on each broadcast reception unit, and when there are a plurality of broadcast reception units, the above restriction is imposed on each broadcast reception unit.

  Regarding the number-limited copy permitted, N copies can be generated from the program content stored as “number-limited copy permitted”. The value of N may be based on a standard, for example. When a copy is generated via the high-speed digital interface output, the copy may be performed when the number of copies to be generated can be determined by using a move function or the like. For example, it can be recognized that the interface is IEEE 1394 and the output destination is a device compatible with the DTCP standard. The generated copy is set to “recopy prohibited” or an equivalent state.

  Also, when reproducing and outputting program content stored as “Number Limited Copy Allowed”, the high-speed digital interface performs output of No More Copies defined in DTCP (Digital Transmission Content Protection). . The analog video output and digital audio output can be output as “one generation copy permitted”.

  When the recording medium is a removable recording medium, there is another limitation in addition to FIG. For digital recording of program content to a removable recording medium, digital_recording_control_data of the digital copy control descriptor is “10” and “one generation can be copied” in TV, data service digital recording, or audio service digital recording. When receiving and recording content, even if it is the first generation of the received content, three or more copies are not allowed (for example, when receiving and recording a broadcast on three or more recording media at the same time). Is not recorded). This value (three or more examples) may be based on a standard, for example. In addition, a plurality of one-generation copies having the same recording format are not generated. However, digital recording to an area that the user cannot access for backup purposes is excluded. In addition, the restriction on recording on a digital recording medium is imposed on each broadcast reception unit. When there are a plurality of broadcast reception units, the above restriction is imposed on each broadcast reception unit. If the receiving device has a recording method that does not support digital_recording_control_mode, the program content whose copy_control_type in the digital copy control descriptor is '01' and digital_recording_control_data is '10' is affected by the value of digital_recording_control_mode in the content usage descriptor. First of all, digital recording is performed in the manner of "one generation copy is possible".

  FIG. 13 is a flowchart illustrating an example of a procedure for creating copy information and the number of copies of management information in the case where program content for which one-generation copying is permitted (Copy One Generation) is recorded in the receiving device 3.

  Based on the copy generation control information from the separation / extraction unit 103 and the information indicating whether or not multiple copies are possible, the content management information creation unit 119 determines whether or not multiple copies can be made with “Copy One Generation permitted”. If it is recognized that the program content is added with the indicated information, “01” is input to the copy information of the management information as no more copying, that is, “No More Copies” (SA01).

  For example, the control unit 114 notifies the content management information creating unit 119 whether the recording medium for recording the program content is built-in or removable (SA02).

  If it is removable, for example, “0” is entered as the number of copies of the management information, and the program content cannot be copied, but it can be moved (SA04). Note that the relationship with the operation that does not allow three or more copies described above is copy control when the above is received and recorded (for example, when the first generation copy is generated), for example. The description of FIG. 13 is different in that it is a story of copy control after recording on a recording medium (after the first generation copy is generated).

  If it is built-in, the content management information creation unit 119 determines whether the information indicating whether or not a plurality of copies is possible is “permitted” or “not permitted” (SA03).

  In the case of “No”, for example, “0” is input as the number of copies of the management information, and the program content cannot be copied, but it can be moved (SA04). Of course, deletion is also possible.

  In the case of “permitted”, “N” is input as the number of copies of the management information so that N copies of the program content can be made (SA05).

  By doing so, it is possible to copy a plurality of recorded program contents of one generation without being restricted by time, and the usability can be improved. Further, by determining whether or not a plurality of copies can be made depending on whether the recording medium is built-in or removable, in the case of built-in, the program content is locally encrypted as described above, and among the management information, key information, The copy information and the copy number program can be protected from being illegally falsified by managing them with encryption. On the other hand, in the case of removable, various management methods are conceivable, and there are things that cannot be managed as in the case of the built-in described above, and therefore it is possible that illegal tampering is inevitable. Thus, there is an effect of protecting the content while improving the convenience for the user.

<Copy processing related to copy control information>
FIG. 14 is a flowchart illustrating an example of a procedure for copying program content by the receiving device 3.

  When copying a program content whose management information copy information is “01” (No More Copies) and whose number of copies is “N” (N ≠ 0), it is monitored whether the copy processing has been completed. (SB01).

  If it has been completed, “N−1” (N ≠ 0) is input as the number of copies of the management information of the copy source recording medium so that N−1 copies of the program content can be made, and the copy destination “01” (No More Copies) is entered in the copy information of the management information of the recording medium to make the recopy prohibited state, and “0” is entered in the number of copies of the management information, but the program content cannot be copied, but the move ( (Movement) is possible (SB04).

  If not completed, it is monitored whether the copy process is interrupted (SB02).

  If not interrupted, it is monitored whether the copy process has been completed (SB01).

  If it is interrupted, “N−1” (N ≠ 0) is input as the number of copies of the management information of the copy source recording medium so that N−1 copies of the program content can be made, and the copy destination If a plurality of recording media can be recorded, the program content being copied is erased (SB03). However, in the case of a recording medium that can be recorded only once, the erasure process is not executed because it cannot be erased.

  By doing so, there is an effect that copy generation management of the program content at the copy destination can be reliably performed. Further, even when the copy process is interrupted for some reason, unnecessary program content does not remain at the copy destination, so that it is possible to save the trouble of erasing later and improve usability. In the above erasure, the data on the recording medium may be physically erased, or the management information is erased so that the data on the recording medium exists but cannot be reproduced (indirectly erased). You may do it.

<Move processing related to copy control information>
FIG. 15 is a flowchart illustrating the procedure for moving the program content of the receiving apparatus according to the embodiment.

When the program information whose management information copy information is “01” (No More Copies) and the number of copies is “0” is being moved, it is monitored whether the move process has been completed (SC01).

  If it has been completed, the program content of the recording medium of the move source and the management information related to the program content are deleted, and “01” (No More Copies) is added to the copy information of the management information of the move destination recording medium. The re-copying prohibited state is entered and "0" is entered as the number of copies of the management information, and the program content cannot be copied but moved.

  If not finished, it is monitored whether the move process is interrupted (SC02).

  If it is not interrupted, it is monitored whether the move process has been completed (SC01).

  If it is interrupted, the program content of the part that has not yet been moved to the recording medium of the moving destination and the management information related to this program content during the movement of the moving source recording medium are stored, and the recording of the moving destination has already been performed. Reproduction of program content moved to the medium is disabled. Save the program content in the middle of the move destination recording medium, enter “01” (No More Copies) in the copy information of the management information to prohibit recopying, and enter “0” in the number of copies of the management information Thus, the program content cannot be copied, but can be moved (SC03).

  By doing this, there is an effect that copy generation management of program content at the move destination can be performed reliably. In addition, even if the move process is interrupted for some reason, the program content is stored in each of the recording media of the move source and the move destination, and the program content cannot be viewed by the interrupt, so that the usability is improved. is there. In the above erasure, the data on the recording medium may be physically erased, or the management information is erased so that the data on the recording medium exists but cannot be reproduced (indirectly erased). You may do it.

  In the above description, the recording medium at the copy destination or the move destination is a recording medium that can be managed as re-copying prohibition (No More Copies). If it cannot be managed, copy or move processing is prohibited.

  In the above description, the case of program content transmitted from a broadcasting station has been described. However, the present invention can also be applied to program content other than the broadcasting station such as a program content provider.

  Moreover, the removable recording medium means a recording medium that has an independent form that can be detached from the receiving apparatus and that can be reproduced even by an apparatus having other reproducing functions.

  Also, “move” refers to the movement of program content by disabling playback after copying “No More Copies” program content recorded on a recording medium to another recording medium. Means to do. Here, the disabling of reproduction means that the reproduction cannot be performed by deleting the program content itself, deleting the encryption key, deleting the management information, or the like. In the middle of the move process, it is preferable that program content having a length exceeding 1 minute is not present in both the move source and the move destination in a reproducible state.

  In the above description, for a program content in which “Copy One Generation” is “Allowed to copy a plurality of copies” and the information indicating whether copying is permitted is “possible”, it is determined that a recording medium can be copied. The determination is made depending on whether it is built-in or removable. However, it may be determined that a plurality of copies can be made on a recording medium that can manage a plurality of copies and a recording medium that cannot manage a plurality of copies. Good. Here, the recording medium capable of managing a plurality of copies is, for example, information on the copy information 507, the number of copies 508, and the key information 506 in the management information indicating the contents of the program content described in FIG. File number 503, date and time 504, and the start address of data area and recording size 505 may be included). This means a recording medium that can be managed so that it cannot be tampered with.

  FIG. 16 shows a configuration example of a recording medium (security removable medium) capable of managing such a plurality of copies (also called copy number control or number control copy). In this configuration, a normal area accessible to the user and a tamper-resistant area not accessible to the user are combined in one recording medium. Confidential information stored in the tamper-resistant area can be accessed when authentication is confirmed by an authentication process with a device that can handle this recording medium, so that confidential information can be managed. It has become. By storing and managing the information of the copy information 507, the number of copies 508, and the key information 506 in this tamper resistant area, unauthorized tampering is not performed.

  On the other hand, a recording medium that cannot manage a plurality of copies is information of copy information 507, number of copies 508, and key information 506 (other file number 503, date 504, data area) in the management information indicating the contents of the program content. A recording medium that can not be managed so as to prevent unauthorized tampering.

  FIG. 17 shows copy information of management information in the case of recording a program content for which one-generation copying of a receiving device is permitted (Copy One Generation) in consideration of a recording medium capable of managing a plurality of copies and a recording medium that cannot. 5 is a flowchart illustrating an example of a copy number creation procedure. The difference from FIG. 13 is SD02. 13 may be combined. For example, SD02 may be executed when SA02 is “removable”.

  For example, the control unit 114 determines whether the recording medium for recording the program content is a recording medium that can manage a plurality of copies or a recording medium that cannot manage a plurality of copies, and notifies the content management information creation unit 119 (SD02). ).

  In the case of a recording medium that cannot manage a plurality of copies, for example, “0” is input as the number of copies of the management information, and the program content cannot be copied, but can be moved (SD04). ).

  In the case of a recording medium capable of managing multiple copies, the content management information creation unit 119 determines whether the information indicating whether multiple copies are possible is “possible” or “no” (SD03). In this case, for example, “0” is input as the number of copies of the management information, and the program content cannot be copied, but can be moved (SD04). In the case of “permitted”, “N” is input as the number of copies of the management information, and the program content can be copied N times (SD05).

  By doing so, it is possible to copy a plurality of recorded program contents of one generation without being restricted by time, and the usability can be improved. In addition, a plurality of recording media that cannot manage multiple copies are determined by determining whether or not multiple copies can be made based on whether the recording medium is a recording medium that can manage multiple copies or a recording medium that cannot manage multiple copies. Copy permission can be avoided, and program content can be protected more reliably.

DESCRIPTION OF SYMBOLS 10 ... Reception recording / reproducing part 101 ... Tuner decoding part 102 ... Selector 103 ... Separation / extraction part 104 ... Input buffer part 105 ... Decoding part 106 ... Network interface part 107 ... Buffer management part 108 ... Clock reproduction part 109 ... Time stamp comparison / Output unit 110 ... Time stamp adding unit 111 ... Reading unit 112 ... Writing unit 113 ... Built-in recording medium 114 ... Control unit 115 ... User interface unit 116 ... Output unit 117 ... Fixed clock generating unit 118 ... Removable recording medium 119 ... Content management information Creation unit 120 ... content management information analysis unit

Claims (3)

A control method in a receiving apparatus that has received digital content and copy control information of the digital content,
When the received copy control information indicates copy generation information that permits one generation of copying,
If the recording medium is a recording medium that does not support copy number limit management, recording the digital content in a prohibited state,
When the recording medium is a recording medium corresponding to the management of the copy number limit,
If the received copy control information indicates whether or not to copy a plurality of copies, the digital content copy is prohibited and recorded,
A recording control method for recording digital content in a copyable state up to a predetermined number of copies when the received copy control information indicates that a plurality of copies can be made. The control method according to claim 1, comprising:
When copying the digital content from the recording medium corresponding to the copy number limit management to another recording medium when the received copy control information indicates that N copies can be made as the predetermined number of copies possible If the copy process is interrupted before the copy process is completed, the digital content of the recording medium corresponding to the management of the copy number limit is updated so that up to N-1 copies can be made, and the other recording medium can be updated. A control method for erasing copied digital content. The control method according to claim 1, comprising:
When the received copy control information indicates whether or not to copy a plurality of copies, or when the received copy control information indicates that a plurality of copies can be made but the number of copies that can be made is 0, the copy number limit management When copying digital content from a recording medium compatible with the recording medium to another recording medium, copying digital content from the recording medium corresponding to the management of the copy number restriction to another recording medium, before the transfer process is completed If the transfer process is interrupted, the digital content portion transferred to another recording medium is stored, and the digital content that has not been transferred to the other recording medium is stored in the recording medium corresponding to the copy number limit management. Control method to save the part of.

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