JP2007013610A - Broadcasting device, broadcasting method, broadcasting receiver and broadcast receiving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a broadcasting device, broadcasting method, broadcasting receiver and broadcast receiving method for enabling a user to immediately view and listen to different content of a jump destination when jumping to the content due to channel changing or the like. <P>SOLUTION: A stream generating part 15 generates a stream composed of a series of packets including a time stamp. A key sequence table generating part 12 generates a key sequence table in which data of scramble key is described in accordance with the time stamp. An encryption processing part 16 uses the data of the scramble key corresponding to the time stamp included in a packet for encrypted data transmission to encrypt data to be transmitted by the packet for encrypted data transmission. The stream generating part 15 generates such a stream such that the packet for key sequence table transmission is transmitted prior to transmitting a packet for encrypted data transmission. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a broadcast device, a broadcast method, a broadcast reception device, and a broadcast reception method, and more particularly, a broadcast device that transmits encrypted video data, a broadcast method, a broadcast reception device that receives encrypted video data, and the like. It relates to a broadcast receiving method.

  In digital broadcasting, video and audio data are encrypted and transmitted for content protection and viewing restriction (see, for example, Non-Patent Document 1).

FIG. 9 is a diagram for explaining an encryption method used in conventional digital broadcasting.
Referring to FIG. 9, in the broadcasting apparatus, video and audio data to be transmitted are encrypted using a scramble key. This scramble key is updated about every second. Further, the scramble key is encrypted using the work key, and an ECM (Entitlement Control Message) including the encrypted scramble key is created.

  FIG. 10 is a diagram for explaining a transmission method of encrypted video and audio data and ECM in conventional digital broadcasting.

  Referring to FIG. 10, the broadcasting apparatus multiplexes and transmits video and audio data encrypted with a scramble key and an encrypted scramble key (ECM).

  That is, before transmitting the video and audio data encrypted with the scramble key A, the scramble key A (ECM) encrypted with the work key is transmitted, and the video and audio data encrypted with the scramble key B are transmitted. A scramble key B (ECM) encrypted with a work key is transmitted before transmission, and a scramble key C encrypted with a work key before transmitting video and audio data encrypted with the scramble key C. (ECM) is transmitted. Here, as shown in FIG. 10, the interval at which the scramble key encrypted with the work key is transmitted is about 1 second.

  FIG. 11 is a diagram for explaining an encryption / decryption method used in conventional digital broadcasting.

Referring to FIG. 11, in the broadcast receiving apparatus, the encrypted scramble key is decrypted using the work key, and the encrypted video and audio data is decrypted using the decrypted scramble key. .
Video coding, audio coding and multiplexing standard in digital broadcasting ARIB STD-B32, 1.8 edition, December, H16, Japan Radio Industry Association

  By the way, in the broadcast receiving apparatus, when the user jumps to another content due to channel switching or the like, there is a problem that the user cannot immediately watch the video and audio of the jump destination content.

  FIG. 12 is a diagram for explaining a problem at the time of a jump in a conventional digital broadcast transmission method.

  Referring to FIG. 12, when the video and audio data encrypted with scramble key A is decrypted and reproduced in the broadcast receiving apparatus (time t1 in FIG. 12), encryption is performed with scramble key B by channel switching. Assume that a jump is made to the point of the converted video and audio data (time t2 in FIG. 12).

  Since the broadcast receiving apparatus has not acquired the scramble key B, it cannot decrypt the video and audio data encrypted with the scramble key B, and cannot reproduce these data. The broadcast receiving apparatus acquires the scramble key C at time t3, and then acquires video and audio data encrypted with the scramble key C, and decrypts and reproduces these data with the scramble key C.

  In this way, when jumping to another content by channel switching or the like, the user cannot immediately see the video and audio data of the frame immediately after the jump destination content, but waits for a while (the ECM is the maximum). The video and audio data after several frames from the jump destination can be seen for one second, which is the insertion interval.

  Therefore, an object of the present invention is to provide a broadcasting device, a broadcasting method, a broadcasting receiving device, and a broadcasting receiving method that allow a user to immediately view a jump destination content when jumping to another content by channel switching or the like. Is to provide.

  In order to solve the above problems, the broadcasting apparatus of the present invention includes a stream generation unit that generates a stream composed of a series of packets including a time stamp, and a table that describes scramble key data corresponding to the time stamp. A table generation unit for generating, and an encryption processing unit for encrypting data transmitted in the packet for encrypted data transmission using data of a scramble key corresponding to a time stamp included in the packet for encrypted data transmission. The stream generation unit generates a stream such that the transmission time of the packet for table transmission precedes the packet for encrypted data transmission, and the table transmission packet includes the data of the table, The encrypted data transmission packet includes a data obtained by encrypting the data transmitted in the packet by the encryption processing unit. The inclusion of data.

Preferably, the packet is a TS packet with a time stamp added to the beginning.
Also, the broadcasting method of the present invention uses a step of generating a table describing scramble key data corresponding to a time stamp, and scramble key data corresponding to the time stamp included in the encrypted data transmission packet. Encrypting data to be transmitted in a packet for encrypted data transmission, and generating a stream composed of a series of packets including a time stamp, and the stream generation step includes table transmission A stream is generated so that the transmission time of the packet for the packet is earlier than the packet for the encrypted data transmission. The table transmission packet includes the data of the table, and the packet for the encrypted data transmission is included. Includes data obtained by encrypting data transmitted in the packet.

Preferably, the packet is obtained by adding a time stamp to the beginning of the TS packet.
In addition, the broadcast receiving apparatus of the present invention includes a receiving unit that receives a stream composed of a series of packets including a time stamp, and, when the received packet is a packet for table transmission, from the data of the packet for table transmission. A table processing unit that generates a table describing scramble key data corresponding to a time stamp, and if the received packet is a packet for encrypted data transmission, the time stamp included in the packet for encrypted data transmission A corresponding scramble key data is extracted from the generated table, and the encrypted scramble key data is used to decrypt the encrypted data included in the encrypted data transmission packet using the extracted scramble key data, When there is a jump specification, the encryption / decryption processing unit encrypts the encrypted data immediately after the jump destination packet. The packet for transmission to a decoding start packet after the jump, and executes decryption.

Preferably, the packet is obtained by adding a time stamp to the beginning of the TS packet.
Also, the broadcast receiving method of the present invention includes a reception step of receiving a stream composed of a series of packets including a time stamp, and, when the received packet is a packet for table transmission, from the data of the packet for table transmission. A step of generating a table describing scramble key data corresponding to a time stamp, and corresponding to a time stamp included in the packet for encrypted data transmission when the received packet is a packet for encrypted data transmission An encryption / decryption step including extracting the scramble key data from the generated table and decrypting the encrypted data included in the encrypted data transmission packet using the extracted scramble key data. If a jump is specified for a processing step, immediately after the jump destination packet The packet for transmission the encrypted data and the decoding start packet after the jump, and executes decryption.

  Preferably, the packet is a TS packet with a time stamp added to the beginning.

  According to the present invention, when jumping to another content by channel switching or the like, the user can immediately view the jump destination content.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Configuration of broadcasting device)
FIG. 1 is a functional block diagram of a broadcasting apparatus according to an embodiment of the present invention.

  Referring to FIG. 1, this broadcasting apparatus 10 includes a scramble key storage unit 11, a key sequence table generation unit 12, a key sequence table storage unit 13, a content storage unit 14, an encryption processing unit 16, and a stream generation. Part 15.

  The stream generation unit 15 generates a stream composed of TTS (Timestamped Transport Stream) packets.

FIG. 2 is a diagram illustrating a configuration of a TTS packet.
Referring to FIG. 2, a TTS packet is a TS (Transport Stream) packet with a time stamp added to the head, and includes a time stamp, a header, and a payload.

  The time stamp represents the transmission order of TTS packets. The time stamp of the first TTS packet is 0 (0x0000 — 0000), and the time stamp of the subsequent TTS packet is incremented by one.

  The header is the same as the header of the TS packet. The header includes a PID (packet identifier). The PID represents the type of data transmitted by the TTS packet.

  The payload is the same as the payload of the TS packet. The key sequence table, video data of the same content (same channel), audio data of the same content (same channel), and section data of the same type are divided and transmitted in TTS packets having the same PID.

The scramble key storage unit 11 stores scramble key data.
The key sequence table generation unit 12 generates a key sequence table using the scramble key data in the scramble key storage unit 11.

  The key sequence table describes scramble key data corresponding to the time stamp attached to the TTS packet. When the payload of a TTS packet is encrypted video or audio data, the scramble key data corresponding to the time stamp of the TTS packet is described in the key sequence table.

FIG. 3 is a diagram illustrating an example of a key sequence table.
Referring to FIG. 3, when the time stamp of the TTS packet for transmitting video data or audio data is 0x0000 — 0010 to 0x0000 — 001f, the scramble key data for encrypting the payload portion is the first odd key data column. If the time stamp is 0x0000 — 1010 to 0x0000 — 101f, the scramble key data for encrypting the payload portion is described in the data field of the first even key, and the time stamp is 0x0000 — 2010 to 0x0000 — 201f. In this case, the scramble key data for encrypting the payload part is described in the second odd key data field, and the time stamp is 0x0000 — 3010 to 0x0000 — 301f, the payload part Data scramble key for encrypting are described in the column of data in the second even key.

  The key sequence table storage unit 13 stores the key sequence table generated by the key sequence table generation unit 12.

  The content storage unit 14 stores a plurality of content data to be multiplexed and transmitted (that is, content data of a plurality of channels in the same time zone) and section data (program guide etc.). In the embodiment of the present invention, the content data is assumed to consist of video data and audio data. It is assumed that video data and audio data are encoded in accordance with MPEG (Moving Picture Experts Group) -2 standard.

  The encryption processing unit 16 encrypts data that requires encryption, that is, video data and audio data with a scramble key. That is, the encryption processing unit 16 extracts the scramble key data corresponding to the time stamp included in the TTS packet for transmission of data that requires encryption, that is, video data or audio data, from the key sequence table. The data transmitted by the TTS packet in the video data in the content storage unit 14 or the data transmitted by the TTS packet in the audio data in the content storage unit 14 is encrypted with the key data.

FIG. 4 is a diagram illustrating an example of a TTS stream.
Referring to FIG. 4, a TTS stream is composed of a series of TTS packets. The key sequence table is divided and inserted into the payload of the first 16 TTS packets, that is, the payloads of TTS packets having time stamps of 0x0000 — 0000 to 0x0000 — 000f. Subsequent TTS packets, that is, payloads of TTS packets having a time stamp of 0x0000_0010 or later, include a plurality of content data (that is, content data of a plurality of channels in the same time zone) and section data (to be multiplexed). Program guide etc.) are divided and inserted. However, the video data and audio data constituting the content data are encrypted and inserted.

The transmission unit 17 transmits the generated TTS stream.
(Broadcaster operation)
FIG. 5 is a flowchart showing the operation procedure of the broadcasting apparatus.

  Referring to FIG. 5, key sequence table generation unit 12 generates a key sequence table that describes scramble key data in association with a time stamp attached to a TTS packet, and stores it in key sequence table storage unit 13. (Step S101).

The stream generation unit 15 sets the control variable NT to 0 (step S102).
When the stream generation unit 15 has not read all the data in the key sequence table in the key sequence table storage unit 13 (YES in step S103), the stream generation unit 15 reads 184 bytes of data from the top of the unread portion. When the unread portion is less than 184 bytes, the stream generation unit 15 reads all the unread portions and zero-pads the read data to generate 184 bytes of data (step S104).

  When all the data in the key sequence table has been read (NO in step S103), the stream generation unit 15 generates 184 bytes of data with all bits set to 0 (step S105).

  The stream generation unit 15 generates a TTS packet for key sequence table transmission. That is, the stream generation unit 15 generates a TTS packet having the time stamp as a control variable NT, the header part PID as an ID representing a key sequence table, and the payload part as 184-byte data generated or read as described above. (Step S106).

The transmission unit 17 transmits the generated TTS packet (step S107).
The stream generation unit 15 increments the control variable NT by 1 (step S108).

  When the control variable NT is less than 16 (NO in step S109), the stream generating unit 15 returns to step S103, and when the control variable NT is 16 or more (YES in step S109), the stream generating unit 15 proceeds to step S110.

  Next, when the stream generation unit 15 has not read all of the plurality of content data and section data to be multiplexed and transmitted in the content storage unit 14 (YES in step S110), the stream generation unit 15 performs a predetermined process from the content storage unit 14. In accordance with the order, unread data of either a plurality of content data (video data and audio data) or section data to be multiplexed is read. That is, the stream generation unit 15 receives 184 bytes of data from the beginning of the unread portion of the section data, 184 bytes of data from the beginning of the unread portion of the video data, or 184 bytes of data from the beginning of the unread portion of the audio data. Read out. When the unread portion is less than 184 bytes, the stream generation unit 15 reads all the unread portions and zero-pads the read data to generate 184 bytes of data (step S111).

  When the data read or generated as described above includes section data (YES in step S112), the stream generation unit 15 generates a TTS packet for section data transmission. That is, the stream generation unit 15 generates a TTS packet having the time stamp as the control variable NT, the header part PID as the ID indicating the type of the section data read out, and the payload part as the data generated or read out as described above. (Step S113).

  When the read data includes video data (NO in step S112, YES in step S114), the stream generation unit 15 refers to the key sequence table and extracts the scramble key data corresponding to the control variable NT. (Step S115) The encryption processing unit 16 is instructed to encrypt the read video data with the extracted scramble key data (Step S116).

  Next, the stream generation unit 15 generates a TTS packet for video data transmission. That is, the stream generation unit 15 sets the time stamp as the control variable NT, the PID of the header portion as the ID indicating the type of the read video data (representing the channel and video), and the TTS as the video data obtained by encrypting the payload portion. A packet is generated (step S117).

  When the read data includes audio data (NO in step S114), the stream generation unit 15 refers to the key sequence table and extracts scramble key data corresponding to the control variable NT (step S118). The encryption processing unit 16 is instructed to encrypt the read voice data with the extracted scramble key data (step S119).

  Next, the stream generation unit 15 generates a TTS packet for audio data transmission. That is, the stream generation unit 15 uses the time stamp as the control variable NT, the PID of the header part as the ID indicating the type of audio data (representing the channel and audio), and the payload part as the encrypted audio data TTS. A packet is generated (step S120).

  After steps S113, S117, and S120, the transmission unit 17 transmits the generated TTS packet and returns to step S110 (step S121).

  If NO in step S110, that is, if all the content data and section data belonging to the multiplex transmission target in the content storage unit 14 have been read, the process ends.

(Configuration of broadcast receiver)
FIG. 6 is a functional block diagram of the broadcast receiving apparatus according to the embodiment of the present invention.

  Referring to FIG. 6, this broadcast receiving apparatus 20 includes a receiving unit 21, a TTS decoder 22, a key sequence table processing unit 23, a key sequence table storage unit 24, a section processing unit 25, and an encryption / decryption process. Unit 26, video decoder 27, audio decoder 29, video playback unit 28, and audio playback unit 30.

The receiving unit 21 receives a TTS stream composed of continuous TTS packets.
The TTS decoder 22 checks the type of sequentially received TTS packets during normal reproduction, and the type of TTS packets sequentially received after the jump destination TTS packet when a jump is designated. The TTS decoder 22 outputs a TTS packet for key sequence table transmission to the key sequence table processing unit 23, and the TTS packet outputs a TTS packet for encrypted data transmission to the encryption / decryption processing unit 26 for section data transmission. Are output to the section processing unit 25.

  When the key sequence table processing unit 23 receives the TTS packet for key sequence table transmission from the TTS decoder 22, the key sequence table processing unit 23 extracts the data of the payload part of the TTS packet to construct the key sequence table, and the key sequence table storage unit 24 Save to.

  The key sequence table storage unit 24 stores the key sequence table constructed by the key sequence table processing unit 23.

  When the section processing unit 25 receives a TTS packet for section data transmission from the TTS decoder 22, the section processing unit 25 extracts the data of the payload portion of the TTS packet to construct section data, and performs various processes based on the section data, for example, a program Display the table.

  When receiving the TTS packet for encrypted data transmission from the TTS decoder 22, the encryption / decryption processing unit 26 extracts the scramble key data corresponding to the time stamp of the TTS packet from the key sequence table, and the extracted scramble key The data of the payload part of the TTS packet is decoded with the data. When there is a jump specification, the encryption / decryption processing unit 26 receives a TTS packet for encrypted data transmission immediately after the jump-target TTS packet from the TTS decoder 22, and executes decryption using the TTS packet as a decryption start packet. To do.

The video decoder 27 decodes video data according to the MPEG2 standard.
The audio decoder 29 decodes audio data in accordance with the MPEG2 standard.

The video playback unit 28 plays back the decoded video data.
The audio reproducing unit 30 reproduces the decoded audio data.

(Broadcast receiver operation)
FIG. 7 is a flowchart showing an operation procedure of TTS stream reception processing of the broadcast receiving apparatus.

  First, the reception unit 21 receives a TTS stream composed of continuous TTS packets (step S201).

  The TTS decoder 22 checks the type of sequentially received TTS packets during normal reproduction, and the type of TTS packets sequentially received after the jump destination TTS packet when a jump is designated.

  When the TTS packet is a key sequence table transmission packet, that is, when the time stamp of the TTS packet is (0x0000 — 0000 to 0x0000 — 000f) (YES in step S202), the TTS decoder 22 transmits the TTS packet to the key sequence table processing unit 23. (Step S203).

  Next, the key sequence table processing unit 23 extracts the data of the payload part of the TTS packet, constructs a key sequence table, and stores it in the key sequence table storage unit 24 (step S204).

  On the other hand, when the TTS packet is a packet for transmitting encrypted data (video data and audio data), that is, when the time stamp of the TTS packet is (0x0000 — 0010−) (NO in step S202), the TTS decoder 22 If the PID of the TTS header corresponds to the video data or audio data of the designated channel (YES in step S205), the TTS packet is output to the encryption / decryption processing unit 26 (step S206).

  Next, the encryption / decryption processing unit extracts the scramble key data corresponding to the time stamp of the TTS packet output from the TTS decoder 22 from the key sequence table (step S207), and uses the extracted scramble key data as a TTS packet. In the case of video data, it is output to the video decoder 27, and in the case of audio data, it is output to the audio decoder (step S208).

  If the decrypted data is video data (YES in step S209), the video decoder 27 decodes the video data output from the encryption / decryption processing unit and outputs the decoded video data to the video playback unit 28 (step S210).

  Next, the video reproduction unit 28 constructs video data from the data output from the video decoder 27 and reproduces the video data (step S211).

  If the decrypted data is audio data (NO in step S209), the audio decoder 29 decodes the audio data output from the encryption / decryption processing unit and outputs it to the audio reproduction unit 30 (step S212).

  Next, the audio reproducing unit 30 constructs audio data from the data output from the audio decoder 29, and reproduces the audio data (step S213).

  Further, the TTS decoder 22 determines that the TTS packet is a packet for section data transmission, that is, when the time stamp of the TTS packet is (0x0000 — 0010−) (NO in step S202), and the PID of the TTS header is converted to the section data. If it corresponds (NO in step S205), the TTS packet is output to the section processing unit 25 (step S214).

  Next, the section processing unit 25 extracts the data of the payload portion of the TTS packet to construct section data, and performs various processes based on the section data, for example, display of a program guide (step S215).

  After steps S204, S211, S213, and S215, if there is an unprocessed TTS packet in the received TTS stream (YES in step S216), the process returns to step S202.

(Concrete example)
FIG. 8 is a diagram for explaining an operation at the time of a jump in the transmission method according to the embodiment of the present invention.

  Referring to FIG. 8, when a broadcast receiving apparatus decodes and reproduces a TTS packet with a time stamp of 0x0000 — 0102 (t1 in the figure), a TTS packet with a time stamp of 0x0000 — 0105 (in the figure) is switched by channel switching. It is assumed that a jump is made to t2).

  When the broadcast receiving apparatus receives the TTS packet for encrypted data transmission immediately after the jump destination TTS packet, the broadcast receiving apparatus recognizes that the time stamp of the TTS packet is 0x0000 — 0106, and the broadcast receiving apparatus corresponds to the time stamp of 0x0000 — 0106. The scramble key data to be extracted is extracted from the key sequence table. Then, the broadcast receiving apparatus decrypts the payload of the TTS packet with the extracted scramble key.

  As described above, in the embodiment of the present invention, when jumping to another content by channel switching or the like, the key sequence table is used from the time stamp of the encrypted data transmission TTS packet immediately after the jump destination TTS packet. Since the scramble key data obtained by encrypting the payload of the encrypted data transmission TTS packet immediately after that can be extracted, the encrypted data transmission TTS packet immediately after that can be decrypted, and the user does not feel the waiting time. You can watch the content of the jump destination. As a result, it is possible to avoid the problem that the content at the jump destination cannot be viewed unless waiting for a maximum of 1 second (interval at which ECM is inserted) as in the prior art.

(Modification)
The present invention is not limited to the above embodiment, and includes, for example, the following modifications.

(1) About Key Sequence Table In the embodiment of the present invention, the broadcasting device first generates a key sequence table including scramble key data, and then encrypts the scramble key data from the key sequence table when performing encryption. Although extracted, it is not limited to this.

  The broadcasting device creates a table that defines only the correspondence between the time stamp and the scramble key (or stores the table created in advance), and specifies the scramble key based on this table when performing encryption. The specified scramble key data may be read from the scramble key storage unit.

(2) Time stamp In the embodiment of the present invention, the time stamp of a TTS packet is incremented by one as the subsequent one is not limited to this, and the correspondence between the time stamp and the scramble key is not limited to this. Any time stamp may be used as long as a predetermined table is transmitted. Therefore, the number to be increased may be an arbitrary number or may vary. Or it may decrease as the subsequent ones decrease.

(3) TTS packet In the embodiment of the present invention, the packet to be transmitted is a packet with a time stamp added to the beginning of the TS packet. However, the present invention is not limited to this, and any packet including a time stamp may be used. . However, it is necessary to prevent the packet size from being too large in order to reduce the waiting time for viewing at the time of jumping. Specifically, in order to reduce the waiting time at the time of jumping as compared with the prior art, it is necessary to set the packet size such that the packet transmission time = (packet size / transmission speed) does not exceed 1 second.

(4) Intra-program jump In the embodiment of the present invention, the case where an inter-program jump occurs due to channel switching has been described. However, a decoding process can also be performed in the same way when a intra-program jump occurs. it can.

(5) Extraction of scramble key from key sequence table In the embodiment of the present invention, at the time of jump processing, a TTS packet for encrypted data transmission immediately after the jump destination TTS packet is received (that is, after jumping). The time stamp of the TTS packet is examined, the scramble key data corresponding to the time stamp is extracted from the key sequence table, and the payload of the received TTS packet is decrypted with the extracted scramble key. is not. For example, in a program jump in which time is specified, the time stamp of the TTS packet for encrypted data transmission immediately after the jump destination TTS packet may be calculated. In such a case, the key sequence table before the jump is calculated. The scramble key data may be extracted from.

  That is, when the time stamp of the TTS packet for encrypted data transmission immediately after the jump destination TTS packet can be calculated, the scramble key data corresponding to the time stamp calculated from the key sequence table is extracted. Alternatively, the encrypted data transmission TTS packet immediately after the jump destination TTS packet may be received (that is, after jumping), and the payload of the TTS packet may be decrypted with the extracted scramble key.

(6) Repetitive transmission of key sequence table In the embodiment of the present invention, the key sequence table is transmitted before the content data is transmitted by transmitting the key sequence table with the first 16 TS packets in the stream. However, the key sequence table may be transmitted by being embedded in the stream periodically or randomly. As a result, the content can be viewed from the middle.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a functional block diagram of the broadcasting apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of a TTS packet. It is a figure showing the example of a key sequence table. It is a figure showing the example of a TTS stream. It is a flowchart showing the operation | movement procedure of a broadcasting apparatus. It is a functional block diagram of the broadcast receiving apparatus which concerns on embodiment of this invention. It is a flowchart showing the operation | movement procedure of the reception process of the TTS packet of a broadcast receiver. It is a figure for demonstrating the operation | movement at the time of the jump in the transmission system of embodiment of this invention. It is a figure for demonstrating the encryption system used by the conventional digital broadcasting. It is a figure for demonstrating the transmission method of the image | video or audio | voice data and ECM which were encrypted in the conventional digital broadcasting. It is a figure for demonstrating the encryption / decryption system used by the conventional digital broadcasting. It is a figure for demonstrating the problem at the time of the jump in the transmission system of the conventional digital broadcast.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Broadcast apparatus, 11 Scramble key memory | storage part, 12 Key sequence table production | generation part, 13 Key sequence table memory | storage part, 14 Content storage part, 15 Stream production | generation part, 16 Encryption processing part, 17 Transmission part, 20 Broadcast reception apparatus, 21 Reception Unit, 22 TTS decoder, 23 key sequence table processing unit, 24 key sequence table storage unit, 25 section processing unit, 26 encryption / decryption processing unit, 27 video decoder, 28 video playback unit, 29 audio decoder, 30 audio playback unit.

Claims (8)

A stream generation unit that generates a stream composed of a series of packets including a time stamp;
A table generation unit for generating a table describing scramble key data corresponding to the time stamp;
An encryption processing unit that encrypts data to be transmitted in the encrypted data transmission packet using scramble key data corresponding to a time stamp included in the encrypted data transmission packet;
The stream generation unit generates a stream such that a time for transmitting a packet for table transmission is earlier than a packet for encrypted data transmission, and the table transmission packet includes data of the table. However, the encrypted data transmission packet includes data obtained by encrypting data transmitted in the packet by the encryption processing unit.   The broadcasting apparatus according to claim 1, wherein the packet is a TS packet with the time stamp added to a head thereof. Generating a table describing scramble key data corresponding to a time stamp;
Encrypting data to be transmitted in the encrypted data transmission packet using scramble key data corresponding to a time stamp included in the encrypted data transmission packet,
A stream generation step of generating a stream composed of a series of packets including the time stamp,
The stream generation step generates a stream in which a packet for table transmission is transmitted earlier than a packet for encrypted data transmission, and the table transmission packet includes the data of the table. A broadcast method in which the encrypted data transmission packet includes data obtained by encrypting data transmitted in the packet.   The broadcasting method according to claim 3, wherein the packet is a TS packet with the time stamp added to a head thereof. A receiving unit for receiving a stream composed of a series of packets including a time stamp;
When the received packet is a table transmission packet, a table processing unit that generates a table describing scramble key data corresponding to a time stamp from the data of the table transmission packet;
When the received packet is an encrypted data transmission packet, the scramble key data corresponding to the time stamp included in the encrypted data transmission packet is extracted from the generated table, and the extracted scramble key An encryption / decryption processing unit for decrypting encrypted data included in the packet for encrypted data transmission using the data of
When the jump designation is made, the encryption / decryption processing unit executes the decryption using the encrypted data transmission packet immediately after the jump destination packet as a decryption start packet after the jump.   The broadcast receiving apparatus according to claim 5, wherein the packet is obtained by adding the time stamp to a head of a TS packet. A receiving step of receiving a stream composed of a series of packets including a time stamp;
When the received packet is a packet for table transmission, generating a table describing scramble key data in correspondence with a time stamp from the data of the table transmission packet;
When the received packet is an encrypted data transmission packet, the scramble key data corresponding to the time stamp included in the encrypted data transmission packet is extracted from the generated table, and the extracted scramble key And decrypting the encrypted data included in the packet for encrypted data transmission using the data of
The broadcast receiving method, wherein when the jump is designated, the encryption / decryption processing step uses the encrypted data transmission packet immediately after the jump destination packet as a decryption start packet after the jump, and executes the decryption.   The broadcast receiving method according to claim 7, wherein the packet is obtained by adding the time stamp to a head of a TS packet.

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