JP4928227B2 - Scramble device, scrambling related information multiplexing method, scrambling related information multiplexing program, and descrambling device - Google Patents

Description

  The present invention relates to a scrambling technique for scrambling a transport stream distributed by broadcast waves or the like.

In recent years, in terrestrial digital broadcasting, as a broadcasting service for mobile devices, a so-called one-segment service that divides a 6 MHz broadcast wave into 13 bands (segments) and broadcasts in a band for one segment (partial reception band) Has been started. This one-seg service does not currently encrypt (scramble) broadcast programs.
On the other hand, a broadcast program in digital broadcasting is scrambled on the broadcaster side (transmission side), and the broadcast program can be viewed only by a limited viewer. A right protection method is realized in which a broadcast program can be supplied only to a receiving device that complies with the correct usage conditions.

In general, in such limited reception broadcasting, a processing unit that scrambles a transport stream of a broadcast program with a scramble key, and scramble related information for releasing scramble in a receiving device (limited reception related information such as ECM, EMM, etc.) Is separated from the processing unit that multiplexes the data into the transport stream. In this case, the process for synchronizing the update of the scramble key and the update of the scramble related information becomes complicated.
Therefore, the data stream is scrambled with the scramble key, the transmission rate of the stream is increased, and the scramble related information is multiplexed and the scramble related information is multiplexed in the increased bandwidth. A technique for easily synchronizing the update is disclosed (see Patent Document 1).
Japanese Patent Laying-Open No. 2002-77848 (paragraphs 0015 to 0020, FIG. 1)

In the above-described one-segment service, broadcast programs are not scrambled, and scramble-related information distributed by limited reception broadcasting is not distributed. On the other hand, in the 1Seg service, there is a great demand for scrambled broadcast programs from the viewpoint of copyright protection.
However, in narrow-band broadcasting such as a one-segment service, it is inefficient to separately secure a band for transmitting additional information such as scramble related information as in Patent Document 1. Further, such a band for transmitting additional information imposes pressure on a band for transmitting a broadcast program, and the quality of the broadcast program must be reduced by scrambling, which is not preferable. This problem can be said not only in the one-segment service but also in the current limited reception broadcasting, and how to effectively use the precious transmission band is a big problem.

  Also, when adding a scramble function to a one-segment service, etc., it is not desirable to change the system configuration on the transmitting side that is currently in operation, and it is easy to realize the scramble function in the current system. It may be a big problem.

  The present invention has been made to solve the above-described problems, and can use additional information (scramble related information) for scrambling a broadcast program without separately securing a band. It is another object of the present invention to provide a scramble apparatus, a scramble related information multiplexing method, a scramble related information multiplex program, and a descramble apparatus that can easily add a scramble function to a currently operated system.

  The present invention has been developed to achieve the above object, and first, the scramble apparatus according to claim 1 generates a scramble key and scramble related information in the scramble apparatus that scrambles the transport stream. Scrambling control means; packet scrambling means for scrambling packets; and related information multiplexing means for multiplexing the scramble related information in the transport stream, wherein the related information multiplexing means constitutes the transport stream The scramble related information generated by the scramble control means is inserted into the packet for time information transmission, which is a kind of packet to be transmitted, and multiplexed within the data length of the packet.

In this configuration, the scrambling device, the scrambling control means, a kind of packets constituting the scramble key for scrambling the transport stream, a scramble-related information for canceling the scramble at the receiving device, the transport stream Are generated at a predetermined time interval longer than the transmission interval of the time information transmission packet . Here, the scramble-related information is information including a descrambling key currently used for descrambling and a descrambling key to be used next, and the scramble control means determines each descrambling key. , Alternately generated and updated at predetermined time intervals.
Further, the scrambler scrambles a packet (transport stream packet) constituting the transport stream by the scramble key by the packet scramble means.

Further, the scrambler multiplexes the scramble related information in the transport stream by the related information multiplexing means.
At this time, the related information multiplexing means converts the time information into the time information transmission packet for transmitting the time information to the receiving device, for example, within 188 bytes which is the data length of the transport stream packet (TS packet) in the terrestrial digital broadcasting system. By inserting and multiplexing the scramble related information, the scramble related information can be transmitted as a part of the time information transmission packet. The time information represents PCR (Program Clock Reference) in the case of using MPEG-2 such as digital terrestrial broadcasting (ISDB-T).

The time information can be multiplexed into a general packet such as video / audio. However, the size of the payload differs between a packet with time information multiplexed and a general packet, so in real-time data such as video and audio, it is difficult to packetize the data according to the size of the payload. It is. Further, since the transmission interval of time information is not particularly related to data such as video / audio, packetization is more difficult. For this reason, time information is generally transmitted as an independent packet (time information transmission packet). In this case, the payload of the time information transmission packet is not used for other purposes.
Therefore, in the present invention, the scramble related information is multiplexed in the time information transmission packet.

Further, the scrambling apparatus according to claim 1, prior SL-related information multiplexing means further includes a multiplex target packet detection unit, and configured to include a delay means, and a multiplexing means.

  In such a configuration, the scrambler detects the time information transmission packet to be multiplexed from the transport stream by the multiplexing target packet detection means. Then, the delay means delays the scramble related information generated by the scramble control means until a time information transmission packet is detected. Then, the scrambler multiplexes the scramble related information into the time information transmission packet by the multiplexing means.

Further, in the scramble apparatus according to claim 1 , the related information multiplexing means may insert the scramble related information into the payload of the time information transmission packet (claim 2 ), or the time It may be inserted into the private area of the adaptation field in which the time information in the information transmission packet is described (claim 3 ).
Thereby, the scramble related information can be multiplexed in the time information transmission packet.

Further, the scramble apparatus according to any one of claims 1 to 3 , wherein the scramble related information includes a descramble key for releasing scramble and information related to a broadcast program. However, common information distributed to all receiving devices may be handled (Claim 4 ), including identification information for individually identifying the receiving device and contract information for individually controlling the receiving device. Individual information may be handled (claim 5 ).
This scramble-related information represents, for example, ECM (Entitlement Control Message) that is common information and EMM (Entitlement Management Message) that is individual information in the digital terrestrial broadcasting system (ISDB-T).

The scramble related information multiplexing method according to claim 6 is a scramble device that scrambles a transport stream with a scramble key, and scrambles scramble related information for releasing the scramble in the transport stream. A related information multiplexing method comprising a key information generation step, a delay step, a packet detection step, and a multiplexing step.

In this procedure, the scramble-related information multiplexing method is a key information generation step in which a scramble control means transmits a scramble key and scramble-related information to a time information transmission packet that is a type of packet constituting a transport stream. It is generated at a predetermined time interval longer than the interval . Here, the scramble-related information is information including a descrambling key currently used for descrambling and a descrambling key to be used next, and the scramble control means determines each descrambling key. , Alternately generated and updated at predetermined time intervals.
In the scramble related information multiplexing method, the output of the scramble related information generated by the scramble control means is delayed by the delay means in the delay step.
Then, the scramble-related information multiplexing method, the packet detecting step, by multiplexing the target packet detection unit, from the transport stream, detects the time information transmission packet time.
In the scramble related information multiplexing method, in the multiplexing step, the scramble related information delayed by the delay means is multiplexed on the time information transmission packet detected by the multiplexing target packet detecting means.

The scramble-related information multiplexing program according to claim 7 is a scrambler that scrambles a transport stream with a scramble key, and multiplexes scramble-related information for releasing the scramble in the transport stream. Further, the computer is configured to function as scramble control means, delay means, multiplexing target packet detection means, and multiplexing means.

In such a configuration, the scramble related information multiplexing program determines in advance by the scramble control means that the scramble key and the scramble related information are longer than the transmission interval of the time information transmission packet which is a kind of packet constituting the transport stream. Generate at different time intervals . Here, the scramble-related information is information including a descrambling key currently used for descrambling and a descrambling key to be used next, and the scramble control means determines each descrambling key. , Alternately generated and updated at predetermined time intervals.
The scramble related information multiplexing program delays the output of the scramble related information generated by the scramble control means by the delay means. Then, the scramble-related information multiplexed program by the multiplexing target packet detecting means detects the time information transmission packet when the transport stream.
Thereafter, the scramble related information multiplexing program multiplexes the scramble related information delayed by the delay means on the time information transmission packet detected by the multiplexing target packet detection means by the multiplexing means.

Furthermore, the descrambling device according to claim 8 is a descrambling device that decodes the transport stream scrambled by the scrambling device according to claim 1, and includes an extraction target packet detection unit, a related information extraction unit, And a packet descrambling means.

In this configuration, the descrambling device detects the packet for time information transmission in which the scramble related information is multiplexed from the transport stream by the extraction target packet detection means. The descrambling device detects the scramble related information from the time information transmission packet when the extraction target packet detection unit detects that the scramble related information is multiplexed in the time information transmission packet. To extract. Then, the descrambling device descrambles the packets constituting the transport stream by the packet descrambling unit based on the scramble related information extracted by the related information extracting unit.

The present invention has the following excellent effects.
Claim 1, according to the invention described in 請 Motomeko 6 or claim 7, since it is not necessary to send secured separately bandwidth scramble-related information, it is possible to effectively utilize the transmission band. Further, according to the present invention, since the band for transmitting the broadcast program is not compressed, deterioration of the quality of the broadcast program due to scramble can be suppressed.
In addition, for example, even in a broadcasting format with a narrow band such as a one-segment service, it is possible to send scramble related information without squeezing a broadcast program, and it is possible to scramble a transport stream.
Further, according to the present invention, it is possible to scramble after multiplexing a transport stream and before remultiplexing or after performing remultiplexing and before performing modulation. The scramble function can be added while using the multiplexer, remultiplexer, etc.

According to the second or third aspect of the invention, since the scramble related information can be multiplexed in the time information transmission packet, the scramble related information can be used without using a separate packet for sending the scramble related information. Information can be transmitted to the receiving device. As a result, it is not necessary to secure and send the scramble related information separately, so that the transmission band can be used effectively.

According to the invention described in claim 4 or claim 5 , as the scramble related information, it is possible to send the common information and the individual information of the receiving apparatus without securing a separate band.
According to the invention described in claim 8 , it is possible to detect the scramble related information by detecting the time information transmission packet from the transport stream. Thus, it is not necessary to secure a band for specific scramble related information.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Configuration of Scrambler (First Embodiment)]
First, the configuration of the scrambler according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a schematic configuration of a scrambling apparatus according to the first embodiment of the present invention. In FIG. 1, the peripheral system (program encoder / multiplexer 2, remultiplexer 3, modulator 4) related to the scrambler 1 is described as a transmission system S.

  The scrambler 1 scrambles a transport stream (hereinafter simply referred to as TS) generated by a program encoder / multiplexer 2 and distributed by broadcast waves. Note that the scrambler 1 multiplexes scramble related information, which is information for descrambling, into a transport stream without securing a separate band. The detailed configuration of this scrambler will be described later.

  A program encoder / multiplexer (multiplexer) 2 encodes baseband data of a broadcast program (program) including video, audio, data, and the like, and multiplexes each data to obtain MPEG-2 Systems ( A TS defined in ISO / IEC 13818-1) is generated.

The remultiplexer 3 remultiplexes the TS scrambled by the scrambler 1 for each organized channel. As a result, TSs of a plurality of organization channels are combined into one TS. The synthesized TS is output to the modulation device 4.
Note that the remultiplexing apparatus 3 may remultiplex the TS scrambled by the scramble apparatus 1 for each layer. As a result, for example, a one-segment layer TS and a twelve-segment layer TS are combined into one TS.
The modulation device 4 modulates TS by a modulation method suitable for the transmission path. For example, when a TS is distributed by terrestrial digital broadcasting, the TS is modulated by an Orthogonal Frequency Division Multiplexing (OFDM) method.

  Hereinafter, the configuration of the scrambler 1 according to the first embodiment will be described in detail with reference to FIG. 2 (refer to FIG. 1 as appropriate). FIG. 2 is a block diagram showing a detailed configuration of the scrambler according to the first embodiment of the present invention. As shown in FIG. 2, the scrambler 1 includes a packet scramble unit 11, a scramble control unit 12, and a related information multiplexing unit 13.

  The packet scramble means 11 sequentially inputs TS packets constituting the TS from the program encoder / multiplexer 2 and scrambles the TS packets with the scramble key generated by the scramble key generation means 12a of the scramble control means 12 described later. To do. The scrambled TS packet is output to the related information multiplexing means 13.

  The scramble control means 12 generates a scramble key for scramble TS (TS packet) and scramble related information for releasing the scramble. Here, the scramble control unit 12 includes a scramble key generation unit 12a, an ECM generation unit 12b, a work key generation unit 12c, and an EMM generation unit 12d.

The scramble key generating means 12a is for generating a scramble key for scramble the TS packets constituting the TS in the packet scramble means 11. The scramble key generating unit 12a generates a scramble key periodically (for example, at intervals of 1 second) while the TS is scrambled in the packet scramble unit 11. The generated scramble key is output to the packet scramble means 11.
Further, the scramble key generation means 12a uses a descramble key that is currently used in advance and a descramble key to be used next to the descramble key after the descramble key is reliably distributed to the receiving device. And output to the ECM generation means 12b. Here, each scramble key is realized by alternately using an Even key (even key) and an Odd key (odd key). Here, for example, an Even key and an Odd key are alternately generated and updated every second. A scramble key and a descramble key are a pair, and a key used for scramble is called a scramble key, and a key used for descrambling is called a descramble key. When a symmetric key cryptosystem is used, the same key is used as the scramble key and the descramble key.

  The ECM generation unit 12b generates common information (ECM: Entitlement Control Message, hereinafter referred to as ECM) that is commonly distributed to all receiving apparatuses. Here, the ECM generation means 12b is the ECM, the descrambling key (Even key, Odd key) generated by the scramble key generation means 12a, and program information related to the broadcast program (for example, program type, viewing fee, etc.) ) Is encrypted using the work key generated by the work key generation means 12c to generate an ECM. The ECM is output to the related information multiplexing means 13 as scramble related information.

  The work key generating unit 12c generates a work key used for encrypting the ECM in the ECM generating unit 12b. The work key generation unit 12c updates the work key in about one month, for example. The generated work key is output to the ECM generation unit 12b and the EMM generation unit 12d.

  The EMM generating unit 12d generates individual individual information (EMM: Entitlement Management Message, hereinafter referred to as EMM) for each receiving device. Here, the EMM generation means 12d has the same master key Km as the key held by the receiving device, the work key, the identification information for individually identifying the receiving device, and the contract information for individually controlling the receiving device. Is used to generate an EMM. The EMM is output to the related information multiplexing means 13 as scramble related information.

The related information multiplexing means 13 multiplexes the scramble related information into the TS packet scrambled by the packet scramble means 11. The TS packet (transport stream) in which the scramble related information is multiplexed is output to the remultiplexing apparatus 3. The related information multiplexing means 13 adds scramble related information to a TS packet (time information transmission packet: hereinafter referred to as PCR packet) in which time information (PCR: Program Clock Reference, hereinafter referred to as PCR) is inserted. insert.
Here, the related information multiplexing unit 13 includes a PCR packet detection unit 13a, a delay unit 13b, and a multiplexing unit 13c.

The PCR packet detection means (multiplexing target packet detection means) 13a detects a TS packet (PCR packet) including a PCR to be multiplexed with scramble related information from the TS output from the packet scramble means 11. It is. This PCR packet can be detected when the packet identifier (PID) of the TS packet has the same value as the time information identifier (PCR_PID) of the program map table (PMT).
The PCR packet detecting means 13a detects the PCR packet while the scramble related information is delayed by the delay means 13b. When a PCR packet is detected, the PCR packet detection unit 13a notifies the multiplexing unit 13c together with the PCR packet and the fact that the PCR packet has been detected. If no PCR packet is detected, the PCR packet detection means 13a outputs the TS packet to the multiplexing means 13c as it is.

  The delay means 13b delays the output of the scramble related information (ECM, EMM) generated by the scramble control means 12. The delay means 13b temporarily stores scramble related information in a storage means such as a memory (not shown). The scramble related information delayed by the delay means 13b is read by the multiplexing means 13c.

  The multiplexing unit 13c reads the scramble related information delayed by the delay unit 13b at the timing when the PCR packet detecting unit 13a detects the PCR packet, and then inserts the scramble related information into the PCR packet for multiplexing. It is.

Here, with reference to FIG. 3 (refer to FIG. 2 as appropriate), an area where the multiplexing means 13c inserts the scramble related information into the TS packet will be described. FIG. 3 is a data structure diagram showing the structure of a TS packet including PCR.
As shown in FIG. 3, the TS packet has a fixed length of 188 bytes, and includes a 4-byte header part, a variable-length adaptation field, and a variable-length payload. Conventionally, when PCR is transmitted, the adaptation field of the TS packet has a minimum length of 8 bytes including a 2-byte area including a field length and a flag indicating the presence / absence of an area, and a 6-byte area that is a PCR area. Only the area for the remaining minutes is used, and the remaining maximum 176 bytes of the TS packet are not used.
Therefore, the multiplexing means 13c inserts the scramble related information into the payload A of the TS packet as shown in FIG. Note that the scramble related information may be inserted into the private area B area.

  By configuring the scrambler 1 in this way, the scrambler 1 can multiplex the scramble related information by using an area that is not conventionally used in the PCR packet when the transport stream is scrambled. .

Here, the scrambler 1 has been described as being provided between the program encoder / multiplexer 2 and the remultiplexer 3 as shown in FIG. 1, but as shown in FIG. good even be provided between the multiplexer 3 a modulator 4 (transmission system S _B). FIG. 4 is a configuration diagram showing another arrangement configuration of the scrambler. As shown in FIG. 4, the scrambler 1 scrambles the final multiplexed transport stream performed in the remultiplexer 3.
According to the configuration shown in FIG. 1 or FIG. 4 described above, the scrambler 1 can scramble individual TSs, no matter how the TSs of a plurality of organized channels are multiplexed. Also, according to these configurations, the timing relationship between TSs is maintained for services that perform multiplexing and re-multiplexing, and therefore, TS timing management becomes easy.

[Operation of Scrambler (First Embodiment)]
Next, the operation of the scrambler 1 will be described with reference to FIG. FIG. 5 is a flowchart showing the operation of the scrambler according to the first embodiment of the present invention. Here, as an example of the scramble related information, an operation of multiplexing ECM (scramble related information multiplexing method) will be described.

(Key information generation step)
First, the scrambler 1 determines whether or not the scramble key generation unit 12a has reached the timing for updating the scramble key at a predetermined time interval (for example, 1 second) by a timer (not shown) (step S1).
Here, when it is time to update the scramble key (Yes in step S1), the scramble device 1 generates a scramble key (Even key or Odd key) by the scramble key generation means 12a (step S2). Proceed to step S3. On the other hand, if it is not yet time to update the scramble key (No in step S1), the scrambler 1 proceeds to step S3 without generating a scramble key.

Then, the scrambler 1 determines whether or not the TS packets constituting the sequentially input TS are scrambled TS packets by the packet scramble unit 11 (step S3). Yes), the TS packet is scrambled with a scramble key (Even key or Odd key) (step S4), and the process proceeds to step S5.
On the other hand, when the TS packet is not a scramble target (No in step S3), the scrambler 1 proceeds to step S5 without performing scramble.

(Delay step)
Subsequently, the scrambler 1 determines whether the timing for generating the ECM is reached by the scramble key generating unit 12a by the ECM generating unit 12b (step S5).
Here, when it is time to generate the ECM (Yes in step S5), the scrambler 1 uses the work key generated in advance by the work key generation unit 12c by the ECM generation unit 12b to scramble key generation unit. The ECM is generated by encrypting the scramble key (Even key, Odd key) generated in 12a and the program information related to the broadcast program (step S6). Then, the scrambler 1 delays the ECM generated in step S6 by the delay unit 13b (step S7). Then, the process proceeds to step S8.
On the other hand, when it is not time to generate the ECM (No in step S5), the scrambler 1 proceeds to step S8 without generating the ECM.

(Packet detection step)
Then, the scrambler 1 determines whether there is a delayed ECM by the PCR packet detector 13a (step S8).
If there is a delayed ECM (Yes in step S8), the scrambler 1 determines whether the TS packet output from the packet scrambler 11 is a PCR packet by the PCR packet detector 13a. (Step S9).

(Multiplexing step)
If the TS packet is a PCR packet (Yes in step S9), the scrambler 1 multiplexes the ECM delayed in step S7 on the PCR packet by the multiplexing unit 13c (step S10). Then, the process proceeds to step S11.
On the other hand, if there is no delayed ECM (No in step S8), or if the input TS packet is not a PCR packet (No in step S9), the scrambler 1 proceeds directly to step S11.

Then, the scrambler 1 outputs the TS packet in which the ECM generated in step S10 is multiplexed or the TS packet in which the ECM is not multiplexed to the outside (step S11).
Thereafter, when the input of the TS is continued (No in step S12), the scrambler 1 returns to step S1 and continues the operation. On the other hand, when the input of the TS is completed (Yes in step S12), the scrambler 1 ends the operation.
Through the above operation, the scrambler 1 can generate a scrambled TS by multiplexing the ECM with the TS packet including the PCR.

(Example of timing for multiplexing scramble related information)
Here, referring to FIG. 6 (refer to FIG. 2 as appropriate), the timing at which the scrambler 1 multiplexes the scramble related information in the TS in the operation described in FIG. 5 will be described. FIG. 6 is a schematic diagram for explaining the timing at which the scramble related information is multiplexed in the TS in the scramble apparatus according to the first embodiment of the present invention.

As shown in FIG. 6A, TS packets (PCR packets) including PCR are added to the transport stream (TS) input to the scrambler 1 at predetermined intervals.
According to the MPEG-2 Systems (ISO / IEC 13818-1) standard, this PCR transmission interval is an interval of 100 milliseconds or less. Also, in the digital terrestrial broadcasting (ISDB-T) transmission scheme (ARIB STD-B31), the number of PCRs to be transmitted is determined by the mode in one remultiplexed TS (one multiplexed frame). . In mode 1, 1 packet per multiplex frame, in mode 2 2 packets in 1 multiplex frame, and in mode 3 4 packets in 1 multiplex frame must be transmitted at equal intervals. This corresponds to a transmission interval of more than 50 milliseconds.

Thereafter, as shown in FIG. 6B, the scrambler 1 updates the scramble key (Even key E1) at the Ks update timing (E1) and scrambles the TS packet with the new scramble key by the packet scramble means 11. To do.
Here, the packet scramble means 11 alternately uses an Even key (E1, E2,... In the figure) and an Odd key (O1, O2,... In the figure) which are scramble keys Ks generated by the scramble control means 12. And scramble the TS packet.

  Then, as shown in FIG. 6C, at the generation timing of the ECM in accordance with the generation timing of the scramble key Ks, the scramble control means 12 has, for example, two scramble keys when the scramble key Ks “E1” is generated. As described above, an ECM including the scramble key (E1) used this time and the scramble key (O1) generated before is generated. Then, the ECM transmission is delayed until the PCR packet is detected, and when the PCR packet is detected, the ECM packet in which the ECM is multiplexed with the PCR packet is transmitted.

For example, as shown in FIG. 6B, at the update timing of the scramble key (Even key E1), the ECM including “E1 / O2” in FIG. 6C as the scramble key is multiplexed into the PCR packet. In this case, there is a delay in scrambling with the scramble key E1 and transmission of the ECM. However, since the ECM including the scramble key E1 (“E1 / O1”) has already been transmitted before the ECM including “E1 / O2” as the scramble key, the scramble should be normally released in the receiving apparatus. Can do.
Also, as shown in FIG. 6B, when the update timing of the scramble key (Odd key O2) occurs simultaneously with the transmission of the PCR packet, “E2 / O1” in FIG. 6C is used as the scramble key. The containing ECM need not be delayed.

  As described above, even if the ECM transmission is delayed in synchronization with the PCR packet, the scramble key used in the receiving apparatus is not delayed.

  Thereafter, as shown in FIG. 6B, the scrambler 1 updates the scramble key (Even key E1) at the Ks update timing (E1) and scrambles the TS packet with the new scramble key by the packet scramble means 11. To do.

  Here, although all the TS packets other than the PCR packet are scrambled, the program specific information (PSI: Program Specific Information) / program arrangement information (SI: Service Information) Since TS packets of other organization channels are included, there are TS packets that are not scrambled. These can be identified by looking at the PID of the TS packet in the packet scramble means 11.

[Configuration of Scrambler (Second Embodiment)]
Next, the configuration of the scrambler according to the second embodiment of the present invention will be described with reference to FIG. FIG. 7 is a block diagram showing the configuration of the scrambler according to the second embodiment of the present invention. In FIG. 7, the peripheral device associated with the scrambling device 1B (program encoder multiplexer 2, re-multiplexer 3, modulator 4) is described as the delivery system S _C that together. As shown in FIG. 7, the scrambler 1B arranges the packet scrambler 11 and the related information multiplexing unit 13 in the configuration of the scrambler 1 (see FIG. 1) in reverse, the packet scrambler 11B, and the related information This is configured as multiplexing means 13B.

The packet scramble unit 11B and the related information multiplexing unit 13B have the same functions as the packet scramble unit 11 and the related information multiplexing unit 13 described with reference to FIGS. 1 and 2 except that the input source and the output destination are different. Since there is, explanation is omitted.
According to the configuration of the scrambler 1B, the packet scramble unit 11B scrambles the TS after the scramble related information is multiplexed by the related information multiplexing unit 13B.

The scrambler 1B may be provided between the program encoder / multiplexer 2 and the remultiplexer 3 as shown in FIG. 7, or the remultiplexer 3 as shown in FIG. It is good also as providing between the modulation | alteration apparatuses 4 (transmission system _SD ).
Note that the operation of the scrambler 1B is different from the operation of the scrambler 1 (see FIG. 2) described in FIG. 5 only in that the operation of scrambling the TS packet in step S3 is performed immediately before step S11. Therefore, description of the detailed operation is omitted.

(Example of timing for multiplexing scramble related information)
Here, the timing at which the scrambler 1B multiplexes the scramble related information in the TS will be described with reference to FIG. FIG. 9 is a schematic diagram for explaining the timing at which the scramble related information is multiplexed in the TS in the scramble apparatus according to the second embodiment of the present invention.

  As shown in FIG. 9A, TS packets (PCR packets) including PCR at predetermined intervals are added to the transport stream (TS) input to the scrambler 1B.

  Then, as shown in FIG. 9 (b), the scrambler 1B, for example, at the generation timing of the scramble key Ks “E1”, the scramble control means 12 at the generation timing of the ECM matched with the generation timing of the scramble key Ks. As two scramble keys, an ECM including the scramble key (E1) generated this time and the scramble key (O1) generated before is generated. Then, the ECM transmission is delayed until the PCR packet is detected, and when the PCR packet is detected, the ECM packet in which the ECM is multiplexed with the PCR packet is transmitted.

Thereafter, as shown in FIG. 9C, the scrambler 1B updates the scramble key (Even key E1) at the Ks update timing (E1) and scrambles the TS packet with the new scramble key by the packet scramble unit 11B. To do.
Here, the packet scramble unit 11B scrambles the TS packet by alternately using the Even key and the Odd key, which are scramble keys Ks generated by the scramble control unit 12.
The scrambler 1B delays the transmission of the ECM in synchronization with the PCR packet, but this does not delay the scramble key used in the receiver as described with reference to FIG.

In this way, the scrambler 1B can perform ECM multiplexing and scramble key update at the same timing as the scrambler 1 described in FIG.
In the scrambler 1B, the packet scramble unit 11B can scramble the TS in which the scramble related information is multiplexed. Thereby, the packet scramble means 11B can perform an operation based on the scramble related information. For example, the packet scramble means 11B can control the timing of scramble with information via the TS without receiving control from the scramble control means 12.

[Application of scrambler (second embodiment)]
Here, as an example, a method will be described in which the scrambler 1B controls the scramble timing based on the scramble related information.
In this case, the packet scrambler 11B of the scrambler 1B has the configuration shown in FIG. FIG. 10 is a block diagram showing a configuration of packet scramble means of the scramble apparatus according to the second embodiment of the present invention.
As shown in FIG. 10, the packet scramble unit 11B includes an ECM packet detection unit 11a, a delay unit 11b, and a scramble unit 11c.

The ECM packet detecting means (scramble related information detecting means) 11a detects the scramble related information multiplexed on the TS by the related information multiplexing means 13B. Here, it is assumed that the ECM packet detection means 11a detects scramble related information as an ECM and detects a TS packet including the ECM.
Here, when an ECM packet is detected, the ECM packet detection unit 11a notifies the scramble unit 11c together with the ECM packet and the fact that the ECM packet has been detected. When no ECM packet is detected, the ECM packet detection unit 11a outputs the TS packet to the scramble unit 11c as it is.

  The delay means 11b delays the output of the scramble key Ks generated by the scramble control means 12. The delay unit 11b temporarily stores the scramble key in a storage unit such as a memory (not shown). The scramble key delayed by the delay means 11b is read by the scramble means 11c.

The scramble means 11c scrambles the TS packet output from the ECM packet detection means 11a with the scramble key delayed by the delay means 11b. The scramble means 11c reads the scramble key from the delay means 11b and scrambles at the timing when the ECM packet detection means 11a receives notification that the ECM packet has been detected.
Thus, by configuring the packet scramble means 11B, it is possible to match the ECM transmission timing with the scramble key update timing.

(Example of timing for multiplexing scramble related information)
Here, with reference to FIG. 11 (refer to FIG. 8 as appropriate), the timing at which the scramble related information is multiplexed in the TS when the packet scramble means 11B of the scrambler 1B has the configuration described in FIG. . FIG. 11 is a schematic diagram for explaining the timing for multiplexing the scramble related information in the TS in the scramble apparatus according to the second embodiment of the present invention.

  As shown in FIG. 11A, TS packets (PCR packets) including PCR are added to the transport stream (TS) input to the scrambler 1B at predetermined intervals.

  Then, as shown in FIG. 11 (b), the scrambler 1B is configured such that the scramble control means 12 at the generation time of the scramble key Ks “E1” at the generation timing of the ECM in accordance with the generation timing of the scramble key Ks. As two scramble keys, an ECM including the scramble key (E1) generated this time and the scramble key (O1) generated before is generated. Then, the ECM transmission is delayed until the PCR packet is detected, and when the PCR packet is detected, the ECM packet in which the ECM is multiplexed with the PCR packet is transmitted.

  As shown in FIG. 11C, the scrambler 1B delays the scramble key (Even key E1) output from the scramble controller 12 by the delay unit 11b. The scrambler 1B detects the scramble key (in this case, delayed by the delay unit 11b at the stage where the ECM packet detection unit 11a detects the TS packet in which the scramble related information (here, ECM) is multiplexed. The TS packet is scrambled with the Even key E1).

  As described above, the scrambler 1B can set the timing at which the scramble related information is transmitted and the update timing of the scramble key to the same timing. As a result, the ECM processing time on the receiving device side can be used for the scramble key update interval time, and a time margin can be secured.

As mentioned above, although the structure and operation | movement were demonstrated about various embodiment of the scramble apparatus based on this invention, this invention is not limited to this. For example, here, an example in which ECM or EMM is multiplexed into a PCR packet as scramble related information has been described. However, if the PCR packet is within the data length specified by the TS packet, what information is multiplexed It is good to do. For example, initialization data used for scrambling may be multiplexed.
Further, the scramble devices 1 and 1B can be operated by a scramble related information multiplexing program that causes a computer to function as each of the means described above.

[Configuration of receiving device (descramble device)]
Next, the configuration of the receiving apparatus (descrambling apparatus) according to the present invention will be described with reference to FIG. FIG. 12 is a block diagram showing a configuration of a receiving apparatus (descrambling apparatus) according to the present invention.
The receiving device 5 descrambles (decodes) the TS packets constituting the TS scrambled by the scramble devices 1 and 1B (see FIGS. 2 and 8). Here, as shown in FIG. 12, the reception device 5 includes related information separation means 51, descrambling control means 52, and packet descrambling means 53.

  The related information separating means 51 separates and extracts scramble related information from the scrambled TS received via the broadcast receiving means (not shown). Here, the related information separating unit 51 includes a related information packet detecting unit 51a and a separating unit 51b.

  The related information packet detecting means (extraction target packet detecting means) 51a detects a PCR packet (related information packet) in which scramble related information is multiplexed from the scrambled TS. The related information packet detection unit 51a sequentially outputs TS packets to the separation unit 51b, and when a related information packet is detected, notifies the separation unit 51b accordingly.

Separating means (related information extracting means) 51b separates the scramble related information from the TS packet output from the related information packet detecting means 51a when the detection of the related information packet is notified. The separated scramble related information is output to the descrambling control means 52. Here, the scramble related information includes EMM and ECM.
The separating means 51b extracts the scramble related information from the payload A of the TS packet (PCR packet) shown in FIG. 3 or the private area B of the adaptation field. Note that it is assumed in advance whether the scramble-related information is inserted in the payload A or the private area B.

  The descrambling control means 52 controls whether to descramble the TS (TS packet) based on the scramble related information separated by the related information separating means 51. Here, the descrambling control means 52 includes an EMM decoding means 52a, an ECM decoding means 52b, and a viewing determination means 52c.

The EMM decoding unit 52a decodes the EMM among the scramble related information separated by the related information separating unit 51. The EMM decrypting means 52a decrypts the EMM using the master key Km stored in a security module such as an IC card (not shown).
Further, the EMM decrypting unit 52a decrypts the EMM to generate a work key Kw for decrypting the ECM, identification information of the receiving apparatus, contract information, and the like. The work key Kw generated here is output to the ECM decryption unit 52b, and the identification information and contract information of the receiving device are output to the viewing determination unit 52c.

The ECM decoding unit 52b decodes the ECM from the scramble related information separated by the related information separating unit 51. The ECM decryption unit 52b decrypts the ECM using the work key output from the EMM decryption unit 52a.
Further, the ECM decoding means 52b generates scramble key Ks and program information related to the broadcast program by decoding the ECM. The scramble key Ks and program information generated here are output to the viewing determination means 52c.

Whether the viewing determination unit 52c decodes the scrambled TS packet based on the identification information and control information of the receiving device decoded by the EMM decoding unit 52a and the program information decoded by the ECM decoding unit 52b. This is a judgment. For example, the viewing determination unit 52c determines whether or not to decode the TS packet depending on whether or not the received contract information matches the viewing conditions indicated in the program information.
If the viewing determination unit 52c determines that the TS packet can be decrypted, the viewing determination unit 52c outputs the scramble key Ks decrypted by the ECM decryption unit 52b to the packet descrambling unit 53.

The packet descramble means 53 decrypts the TS packets sequentially output from the related information separation means 51 using the scramble key output from the descramble control means 52. The TS decoded by the packet descrambling means 53 is decoded as viewable data by a decoding means such as MPEG-2 (not shown).
By configuring the receiving device 5 in this way, the receiving device 5 can separate and extract the scramble related information multiplexed in the PCR packet, and can perform control such as descrambling.

[Operation of receiving device (descrambling device)]
Next, the operation of the receiving device 5 will be described with reference to FIG. 13 (refer to FIG. 12 as appropriate). FIG. 13 is a flowchart showing the operation of the receiving apparatus (descrambling apparatus) according to the present invention. Here, as an example of the scramble related information, an operation for separating the ECM will be described.

First, the receiving device 5 determines whether the scrambled TS is a PCR packet (related information packet) in which scramble related information is multiplexed for each TS packet in the scrambled TS by the related information packet detection unit 51a ( Step S51). The related information packet can be determined when the packet identifier (PID) of the TS packet has the same value as the ECM packet identifier (ECM_PID) or the EMM packet identifier (EMM_PID).
Here, when the related information packet is detected (Yes in step S51), the receiving device 5 separates and extracts the scramble related information (here, ECM) from the related information packet by the separating unit 51b (step S52). ).

Thereafter, the receiving device 5 uses the ECM decryption unit 52b to decrypt the scramble key and program information from the ECM using the work key decrypted in advance by the EMM decryption unit 52a (step S53). Then, the receiving device 5 updates the scramble key as a new scramble key (step S54), and proceeds to step S55.
On the other hand, when the related information packet is not detected (No in step S51), the reception device 5 proceeds to step S58 without updating the scramble key.

  Then, the receiving device 5 is scrambled by the viewing determination unit 52c based on the identification information and contract information of the receiving device decoded in advance by the EMM decoding unit 52a and the program information decoded by the ECM decoding unit 52b. It is determined (viewing determination) whether or not to decode the TS packet being received (step S55).

If viewing is permitted (“permitted” in step S55), the receiving device 5 descrambles (decodes) the TS packet using the scramble key and outputs it by the packet descrambling means 53 (step S56). .
On the other hand, if viewing is not permitted (“not permitted” in step S55), the receiving device 5 outputs the TS packet as it is without decoding (step S57).

Thereafter, when the input of the scrambled TS is continued (No in Step 58), the receiving device 5 returns to Step S51 and continues the operation. On the other hand, when the input of the TS is completed (Yes in step S58), the receiving device 5 ends the operation.
Through the above operation, the receiving device 5 can separate and extract the ECM from the TS packet (related information packet) including the PCR, and descramble the scrambled TS.

It is a block diagram which shows schematic structure of the scramble apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the detailed structure of the scramble apparatus which concerns on 1st Embodiment of this invention. It is a data structure figure which shows the structure of TS packet containing PCR. It is a block diagram which shows the other arrangement structure of the scramble apparatus which concerns on 1st Embodiment of this invention. It is a flowchart which shows operation | movement of the scramble apparatus which concerns on 1st Embodiment of this invention. It is a schematic diagram for demonstrating the timing which scramble-related information is multiplexed by TS in the scramble apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the structure of the scramble apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the other arrangement | positioning structure of the scramble apparatus which concerns on 2nd Embodiment of this invention. It is a schematic diagram for demonstrating the timing which scrambles related information is multiplexed by TS in the scramble apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the structure of the packet scramble means of the scramble apparatus which concerns on 2nd Embodiment of this invention. It is a schematic diagram for demonstrating the other timing which scrambles relevant information by TS in the scramble apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the structure of the receiver (descrambling apparatus) which concerns on this invention. It is a flowchart which shows operation | movement of the receiver (descrambling apparatus) which concerns on this invention.

Explanation of symbols

S transmission system 1, 1B scrambler 11 packet scramble means 12 scramble control means 12a scramble key generation means 12b ECM generation means 12c work key generation means 12d EMM generation means 13 related information multiplexing means 13a PCR packet detection means (packets to be multiplexed) Detection means)
13b Delay means 13c Multiplex means 2 Program encoder / multiplexer (multiplexer)
3 Remultiplexer 4 Modulator 5 Receiver (descrambler)
51 related information separating means 51a related information packet detecting means (extraction target packet detecting means)
51b Separation means (related information extraction means)
52 Descramble control means 52
52a EMM decoding means 52b ECM decoding means 52c viewing determination means 53 packet descrambling means

Claims (8)

In a scrambler that scrambles the transport stream,
The scramble key for scrambling the transport stream and the scramble related information for releasing the scramble are determined in advance longer than the transmission interval of the time information transmission packet which is a kind of packet constituting the transport stream. Scramble control means for generating at a predetermined time interval ;
Packet scrambling means for scrambling the packets constituting the transport stream with the scrambling key;
And related information multiplexing means for multiplexing the scramble related information in the transport stream,
The related information multiplexing means is
Multiplexing target packet detection means for detecting the time information transmission packet to be multiplexed from the transport stream;
Delay means for delaying the scramble related information generated by the scramble control means until the time information transmission packet is detected;
Multiplexing means for multiplexing the time information transmission packet detected by the multiplexing target packet detection means by inserting and multiplexing the scramble related information delayed by the delay means within the data length of the packet. ,
The scramble related information is information including a descrambling key that is currently used for descrambling and a descrambling key that is used next, and the scramble control means includes each descrambling key, A scrambler, wherein the scrambler alternately generates and updates at the predetermined time interval . The related information multiplexing means includes:
Scrambling apparatus according to claim 1, characterized in that the payload of the time information transmission packet, inserts the scrambling-related information. The related information multiplexing means includes:
Scrambling apparatus according to claim 1, wherein the time information in the time information transmission packet in the private area of the adaptation field are described, which inserts the scrambling-related information. The scrambling-related information, a descrambling key for descrambling, according to claims 1, characterized in that the common information including the information related to the broadcast programs to any one of claims 3 Scrambler. The scrambling-related information includes identification information for individually identifying the receiving device, any of claims 1 to 3, characterized in that the individual information including the contract information for individually controlling the receiving device The scramble device according to one item. A scrambling apparatus for scrambling a transport stream with a scrambling key, a scrambling related information multiplexing method for multiplexing scrambling related information for releasing the scrambling on the transport stream,
Key information generation by the scramble control means for generating the scramble key and the scramble related information at a predetermined time interval longer than a transmission interval of a time information transmission packet which is a kind of packet constituting the transport stream. Steps,
A delay step of delaying the output of the scramble related information generated by the scramble control means by a delay means;
By multiplexing the target packet detection unit, from the transport stream, a packet detecting a transmission packet the time information,
The detected time information transmission packet in the multiplexed target packet detecting means, seen including a multiplexing step of multiplexing the scrambled related information delayed by said delay means,
The scramble related information is information including a descrambling key that is currently used for descrambling and a descrambling key that is used next, and the scramble control means includes each descrambling key, A scramble-related information multiplexing method, wherein the scramble-related information is multiplexed and updated alternately at the predetermined time interval . In a scramble device that scrambles a transport stream with a scramble key, a computer is multiplexed in order to multiplex scramble related information for releasing the scramble in the transport stream.
Scramble control means for generating the scramble key and the scramble related information at a predetermined time interval longer than a transmission interval of a time information transmission packet which is a kind of packet constituting the transport stream ;
Delay means for delaying the output of the scramble related information generated by the scramble control means;
Wherein the transport stream, multiplexed target packet detecting means for detecting a transmission packet the time information,
Function as multiplexing means for multiplexing the scramble related information delayed by the delay means to the time information transmission packet detected by the multiplexing target packet detection means ,
The scramble related information is information including a descrambling key that is currently used for descrambling and a descrambling key that is used next, and the scramble control means includes each descrambling key, A scramble-related information multiplexing program, which is alternately generated and updated at the predetermined time interval . A descrambling device for decoding a transport stream scrambled by the scrambling device according to claim 1,
Extraction target packet detection means for detecting a time information transmission packet in which scramble related information is multiplexed from the transport stream;
Related information extraction means for extracting the scramble related information from the time information transmission packet when the extraction target packet detection means detects that the scramble related information is multiplexed in the time information transmission packet; ,
A descrambling device comprising: a packet descrambling unit that descrambles a packet constituting the transport stream based on the scramble related information extracted by the related information extraction unit.

Images