JP2018085593A - Channel determination device, channel determination method, and program thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform highly-accurate channel determination.SOLUTION: A channel determination device includes: a first acquisition unit that obtains target data that is either ECM data included in a broadcast stream received by a target receiver or information on a scramble key included in the ECM data, from the target receiver which is configured so as to be able to receive the broadcast stream including both a digital broadcast content which is encrypted by the scramble key that differs for each channel and the information on the scramble key relating to encryption of the content; a second acquisition unit that obtains reference data that is either ECM data included in the broadcast stream received by a reference receiver or information on the scramble key included in the ECM data, from the reference receiver which is configured so as to be able to receive the broadcast stream; and a determination unit that determines a channel corresponding to the broadcast stream received by the target receiver, on the basis of information on channels corresponding to the broadcast stream received by the reference receiver and information on whether or not the target data and reference data are matched with each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a channel determination device, a channel determination method, a program thereof, and the like.

  In order to investigate the audience rating of digital broadcasting, it is necessary to detect a channel actually viewed by a receiving device (hereinafter also referred to as “TV”) installed in a viewer's house to be investigated. However, in digital broadcasting with content protection, digital broadcast content is scrambled on the broadcaster side so that only limited viewers and receivers that comply with the correct program usage conditions can view the broadcast program. . For such a scrambled digital broadcast, it is difficult to obtain information about the channel directly from the television.

  One of the methods for determining a channel without acquiring information about the channel from the TV is to transmit the audio data collected by the measuring device installed at the viewer's home to the center device, and the center device determines the channel. There is a matching method.

  For example, Patent Document 1 discloses a channel determination system based on such a matching method. In the system disclosed in Patent Document 1, in a measuring device installed in a viewer's house, a TV is tuned and a TV channel is changed using a change in sound, and a program immediately after the channel is changed. Signature (TV sound detected by microphone, TV screen shot by video camera, etc.) and time data are extracted and stored. Thereafter, the accumulated data is sent to the center device, and the center device compares the received program signature with a reference signature prepared on the center device side to determine a viewing channel.

JP-T 9-503636

  In a system that performs channel determination using sound as described in Patent Document 1, for example, when there is a silent period such as between commercials or when the same sound (for example, commercial) flows in different channels, the channel Judgment cannot be made.

  Therefore, in view of the above circumstances, an object of the present invention is to provide a channel determination device, a channel determination method, and a program for performing channel determination with high accuracy.

  A channel determination apparatus according to an embodiment of the present invention is capable of receiving a broadcast stream including digital broadcast content encrypted with a different scramble key for each channel and information related to the scramble key for encryption of the content. A first acquisition unit that acquires target data that is information related to ECM data included in a broadcast stream received by the target receiver or a scramble key included in the ECM data, and a broadcast stream A second acquisition unit that acquires reference data, which is information related to ECM data included in a broadcast stream received by the reference receiver or a scramble key included in the ECM data, from a reference receiver configured to be receivable; Corresponds to the broadcast stream received at the reference receiver Comprising a Yan'neru information, and whether the target data and the reference data matches, based on, and a determination unit determining a channel corresponding to the broadcast stream received in the target receiver.

  ADVANTAGE OF THE INVENTION According to this invention, the channel determination apparatus, the channel determination method, and its program which can perform a highly accurate channel determination can be provided.

It is a block diagram which shows an example of the system configuration | structure of the channel determination system in one Embodiment of this invention. It is a figure which shows an example of the functional block of the broadcast station system in one Embodiment of this invention. It is a figure which shows an example of the structure of the broadcast stream in one Embodiment of this invention. It is a figure which shows an example of the structure of the ECM section in one Embodiment of this invention. It is a figure which shows an example of the functional block of the television which comprises the object receiver and reference receiver in one Embodiment of this invention. It is a figure which shows an example of the functional block of the channel determination apparatus in one Embodiment of this invention. It is a flowchart which shows the processing flow of the channel determination apparatus in one Embodiment of this invention. It is a figure which shows an example of the hardware constitutions of the channel determination apparatus in one Embodiment of this invention.

[Embodiment]
Hereinafter, one embodiment of the present invention will be described in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention only to the embodiments. The present invention can be variously modified without departing from the gist thereof. Furthermore, those skilled in the art can employ embodiments in which the elements described below are replaced with equivalent ones, and such embodiments are also included in the scope of the present invention. In the following, for ease of understanding, an embodiment in which the present invention is realized using an information processing apparatus will be described as an example. However, as described above, the present invention is not limited thereto.

<1. Overview of system configuration>
FIG. 1 shows an example of the configuration of a channel determination system 1 according to the present embodiment. As shown in FIG. 1, the channel determination system 1 includes a channel determination device 10, a broadcast station system 20, a target receiver 30, and a plurality of reference receivers 40.

  The broadcast station system 20 scrambles digital broadcast content with content protection and transmits it as a broadcast stream (for example, MPEG-2 TS). The target receiver 30 is, for example, a receiver (television) installed at a viewer's house. On the other hand, the plurality of reference receivers 40 are receivers used for channel determination of digital broadcasting being received by the target receiver 30, and the channels of digital broadcasting being received by the reference receiver 40 are known. In the channel determination system 1 according to the present embodiment, in the channel determination device 10, the ECM data included in the broadcast stream being received by the reference receiver 40 and the broadcast stream being received by the target receiver 30 or the work included therein. By determining whether or not the scramble key encrypted by the key matches, the target receiver 30 determines the channel of the digital broadcast being received.

First, the outline of the processing of the channel determination system 1 will be described.
In the broadcast station system 20, a scramble key for encrypting the digital broadcast is generated at a predetermined cycle (for example, every 2 seconds) (STEP 1). Note that the scramble key is generated differently for each broadcasting station (that is, for each channel). Digital broadcast content (video, audio, etc.) is scrambled (encrypted) with the generated scramble key (STEP 2). The generated scramble key is encrypted with the work key (STEP 3). Data including an encrypted scramble key (hereinafter, data including an encrypted scramble key is also referred to as “ECM (Entlement Control Message) data”) is multiplexed with data related to the scrambled content (STEP 4). Is transmitted as a broadcast stream (STEP 5).

  When receiving the broadcast stream, the target receiver 30 and the reference receiver 40 separate the data into scrambled content data (hereinafter also referred to as “packets”) and data (packets) about ECM data (STEP 6). Next, a CAS (Conditional Access System) module decrypts the scramble key from the packet relating to the separated ECM data using the work key stored in advance (STEP 7). Further, the content scrambled with the decrypted scramble key is descrambled to reproduce the digital broadcast (STEP 8).

  The channel determination device 10 acquires packets related to the ECM data separated in STEP 6 from each of the target receiver 30 and the plurality of reference receivers 40 (STEP 9). At this time, the channel determination apparatus 10 synchronizes packets acquired from the target receiver 30 and the plurality of reference receivers 40 (STEP 10), and compares ECM data generated at the same timing (STEP 11). Thereby, in the channel determination device 10, the target receiver 30 has the same channel as any of the reference receivers 40 based on whether the ECM data acquired from the target receiver 30 and the plurality of reference receivers 40 match. It is determined whether or not the digital broadcast is being reproduced (STEP 12). At this time, the entire ECM data may be compared, or a part of the scramble key encrypted with the work key included in the ECM data may be compared. Further, efficient channel determination can be performed by comparing only channels having the same business entity identification and work key identification included in the ECM data. The channel determination system 1 preferably includes the same number of reference receivers 40 as the number of channels, but is not limited thereto, and may be configured to include only the number of reference receivers 40 smaller than the number of channels. In this case, the reference receiver 40 switches and reproduces the channel at a predetermined cycle. In the channel determination device 10, based on the channel of the digital broadcast reproduced by the reference receiver 40 at the timing when the digital broadcast reproduced by the target receiver 30 and the digital broadcast reproduced by the reference receiver 40 match. The digital broadcast channel reproduced by the receiver 30 can be determined.

<2. Broadcasting station system>
The configuration of the broadcast station system 20 will be described with reference to FIG. FIG. 2 is a functional block diagram illustrating an example of the configuration of the broadcast station system 20. As shown in FIG. 2, the broadcasting station system 20 includes a scramble unit 201, an ECM generation unit 202, and a multiplexing unit 203.

  The scramble unit 201 scrambles (encrypts) the input content (video, audio, etc.) using a scramble key. Encryption with the scramble key is performed by a common common key encryption method (for example, MULTI2 encryption). The scramble unit 201 outputs the scrambled content to the multiplexing unit 203. The scramble key is unique for each broadcasting station and is updated about once every few seconds by the scramble unit 201. For example, the scramble key may be updated by appropriately inputting a new scramble key from the outside.

  The ECM generation unit 202 encrypts the scramble key used for scrambling by the scramble unit 201 with a work key, and generates ECM data. The encryption with the work key is performed by a common common key encryption method. The ECM generation unit 202 outputs the generated ECM data to the multiplexing unit 203. The ECM generation unit 202 preferably generates ECM data at a predetermined cycle (for example, every 2 seconds). In this case, the ECM generation unit 202 can encrypt all the scramble keys generated during a predetermined period with the work key and include them in one ECM data.

  The multiplexing unit 203 sequentially multiplexes the ECM data generated by the ECM generation unit 202 on the content scrambled by the scramble unit 201. The multiplexing unit 203 transmits the data generated by multiplexing as a broadcast stream to the target receiver 30 and the reference receiver 40.

  FIG. 3 is a diagram illustrating an example of the structure of a broadcast stream transmitted by the multiplexing unit 203. In the example of FIG. 3, the structure of MPEG-2 TS is shown as an example of a broadcast stream. In this example, the broadcast stream has a structure in which a plurality of TS packets are connected. Content such as video and audio and ECM data are divided into 188-byte TS packets and stored in a broadcast stream.

  The TS packet is composed of a 4-byte TS header and a 184-byte TS payload. In the example of FIG. 3, an ECM section (see FIG. 4) including ECM data is stored in the TS payload, but content may be stored in the TS payload. Further, the TS header includes a synchronization byte (specifically, 0x47) indicating a start code of the TS packet, a PID (Packet Identifier), a PCR (Program Clock Reference), and the like.

  PID is identification information indicating the type of data transmitted by the TS packet. The PID is described in TS packets called PAT (Program Association Table) and PMT (Program Map Table). For example, the same PID is assigned to TS packets including the same type of content of the same program. PCR is standard clock information used to synchronize media (for example, between video and audio).

  FIG. 4 is a diagram illustrating an example of the structure of the ECM section. The ECM section includes an ECM header, an ECM main body, and a CRC (Cyclic Redundancy Check) as disclosed in, for example, ARIB STD-B25 (access control method in digital broadcasting). The ECM header includes a table identifier (specifically 0x82) indicating the start code of ECM data. CRC is information used for error detection. The structure conforms to 222.0.

  Furthermore, the ECM main body has a structure including a fixing portion. The fixed unit includes a protocol number indicating the type of information included in the ECM main body, an entity identification for identifying a provider that distributes content, a work key identification for identifying a work key in which a scramble key is encrypted, and a work key. An encrypted scramble key (odd key, even key) is included. The ECM data shown in FIG. 4 is generated in a cycle of 2 seconds, and one ECM data includes a scramble key currently used (for example, an odd key) and a scramble key (for example, an even key) used in the next cycle. It is included.

<2. Configuration of target receiver and reference receiver>
The configurations of the target receiver 30 and the reference receiver 40 that realize the above-described processing will be described with reference to FIG. FIG. 5 is a functional block diagram of the television 70 and the ECM sensor 80 that constitute the target receiver 30 or the reference receiver 40 according to the present embodiment. The television 70 includes a control unit 701 and a CAS (Conditional Access System) 702 as functional units.

  The control unit 701 separates the broadcast stream received from the broadcast station system 20 into TS packets that include the scrambled content in the payload and TS packets that include the ECM section in the payload (see FIG. 3). For example, the control unit 701 can determine whether the data included in the TS payload is content or an ECM section with reference to the header (PID) of the TS packet. The control unit 701 creates an ECM reception command from the TS packet including the separated ECM section in the payload, and outputs it to the CAS unit 702. The ECM reception command has a structure disclosed in ARIB STD-B25 (access control method in digital broadcasting). Further, the control unit 701 descrambles the content using the decrypted scramble key output from the CAS unit 702 and reproduces the digital broadcast.

  When the CAS unit 702 receives an ECM reception command from the control unit 701, the CAS unit 702 decrypts a scramble key included in the ECM data using a work key stored in advance. In the case of a configuration using a different work key for each broadcasting station, the CAS unit 702 stores a work key and an identifier of the work key in association with each other. In this case, the CAS unit 702 can specify the work key necessary for decrypting the scramble key by referring to the business entity identification and the work key identification included in the ECM main body. Further, the CAS unit 702 outputs the decrypted scramble key to the control unit 701.

  The ECM sensor 80 acquires an ECM reception command including ECM data transmitted from the control unit 701 to the CAS unit 702 and transmits it to the channel determination device 10. The ECM sensor 80 can be connected to the television 70 via a connector of a B-CAS card, for example. Thus, since the ECM sensor 80 according to the present embodiment can be connected to the target receiver 30 and the reference receiver 40 via the B-CAS card connector, the target receiver 30 and the reference receiver 40 are specially modified. The ECM reception command including the ECM data can be acquired without any problem.

<3. Configuration of channel determination device>
Next, the configuration of the channel determination device 10 that realizes the above-described processing will be described with reference to FIG. The channel determination device 10 is a computer connected to the ECM sensor 80 by wire or wireless, and examples thereof include a PC (Personal Computer) and a server device.

  As illustrated in FIG. 6, the channel determination device 10 according to the present embodiment includes an acquisition unit (an example of a first acquisition unit and a second acquisition unit) 101, an extraction unit 102, and a comparison unit 103 as functional units. And have.

  The acquisition unit 101 acquires ECM data acquired by the ECM sensor from the ECM sensor 80 connected to each of the target receiver 30 and the plurality of reference receivers 40. Specifically, the acquisition unit 101 can extract the ECM by referring to the CLA code and the INS code of the ECM reception command. Further, the acquisition unit 101 performs buffering so that the ECM data extracted from the ECM reception commands acquired at close timings can be compared with each other, and the ECM data acquired from the target receiver 30 and the plurality of reference receivers 40 can be compared. Synchronize with.

  The extraction unit 102 acquires ECM data and an encrypted scramble key included in the ECM main body included in the ECM reception command of the target receiver 30 and the reference receiver 40 acquired by the acquisition unit 101. For example, the extraction unit 102 converts the ECM data from the data structure defined as the ECM reception command and the scramble key included in the ECM data (hereinafter referred to as “target scramble key” (an example of target data). The scramble key acquired from the reference receiver 40 is also extracted as a “reference scramble key” (also referred to as an example of reference data). When the ECM data has the structure shown in FIG. 4, the extraction unit 102 receives ECM data or ECM data from each of the ECM reception command acquired from the target receiver 30 and the ECM reception command acquired from the reference receiver 40. The scramble key of both the odd key and the even key included in it is extracted.

  The comparison unit 103 compares the target scramble key acquired by the extraction unit 102 with a plurality of reference scramble keys, and determines whether or not the target scramble key matches any reference scramble key. In the present embodiment, the comparison unit 103 compares the encrypted target scramble key with the reference scramble key, but is not limited to this. The comparison unit 103 may be configured to compare the entire ECM data, or may be configured to compare the target scramble key decrypted with the work key and the reference scramble key. In this case, the comparison unit 103 may decrypt the target scramble key and the reference scramble key using the work key. Further, for example, the ECM sensor 80 may acquire the data output from the CAS unit 702 to the control unit 701 and output the decrypted scramble key to the channel determination device 10.

  It is preferable that the comparison unit 103 performs the above-described comparison process at a cycle in which ECM data is generated. Thereby, when the channel of the digital broadcast reproduced by the target receiver 30 is changed, the change of the channel can be detected immediately.

  As shown in FIG. 4, one encrypted scramble key has a size of 8 bytes, and there is almost no possibility of matching between different channels. In the channel determination device 10 according to the present embodiment, the encrypted scramble key is used for channel determination, so that the broadcast stream channels received by the target receiver 30 and the reference receiver 40 match. Can be determined with high accuracy.

  FIG. 7 is a flowchart showing the flow of channel determination processing in the channel determination device 10. When the channel determination device 10 acquires an ECM reception command from the ECM sensor 80 (S11: YES), the ECM reception acquired from the target receiver 30 with reference to the CLA code and INS code of the ECM reception command received by the acquisition unit 101 is obtained. The command is synchronized with the ECM reception command acquired from the plurality of reference receivers 40 (S12).

  Next, the extraction unit 102 extracts the target scramble key and the reference scramble key from the ECM data (S13). Further, the comparison unit 103 compares the target scramble key with the reference scramble key and determines whether or not they match (S14). If the target scramble key and the reference scramble key match, the comparison unit 103 determines that the digital broadcast channel being received by the target receiver 30 is the digital broadcast channel being received by the reference receiver 40. (S15).

<Hardware configuration>
Hereinafter, an example of a hardware configuration when the above-described channel determination device 10 is realized by the computer 800 will be described with reference to FIG. The function of each device can be realized by dividing it into a plurality of devices.

  As illustrated in FIG. 8, the computer 800 includes a processor 801, a memory 803, a storage device 805, an input I / F unit 807, a data I / F unit 809, a communication I / F unit 811, and a display device 813.

  The processor 801 controls various processes in the computer 800 by executing a program stored in the memory 803. For example, the acquisition unit 101, the extraction unit 102, the comparison unit 103, and the like of the channel determination device 10 can be realized as a program mainly operating on the processor 801 after being temporarily stored in the memory 803.

  The memory 803 is a storage medium such as a RAM (Random Access Memory). The memory 803 temporarily stores a program code of a program executed by the processor 801 and data necessary for executing the program.

  The storage device 805 is a non-volatile storage medium such as a hard disk drive (HDD) or a flash memory. The storage device 805 stores an operating system and various programs for realizing the above-described configurations. Such programs and data are referred to by the processor 801 by being loaded into the memory 803 as necessary.

  The input I / F unit 807 is a device for receiving input from the user. Specific examples of the input I / F unit 807 include a keyboard, a mouse, a touch panel, various sensors, and a wearable device. The input I / F unit 807 may be connected to the computer 800 via an interface such as a USB (Universal Serial Bus).

  A data I / F unit 809 is a device for inputting data from the outside of the computer 800. Specific examples of the data I / F unit 809 include a drive device for reading data stored in various storage media. The data I / F unit 809 may be provided outside the computer 800. In this case, the data I / F unit 809 is connected to the computer 800 via an interface such as a USB.

  The communication I / F unit 811 is a device for performing data communication via the Internet with a device external to the computer 800 in a wired or wireless manner. The communication I / F unit 811 may be provided outside the computer 800. In that case, the communication I / F unit 811 is connected to the computer 800 via an interface such as a USB.

  The display device 813 is a device for displaying various information. Specific examples of the display device 813 include a liquid crystal display, an organic EL (Electro-Luminescence) display, and a wearable device display. The display device 813 may be provided outside the computer 800. In that case, the display device 813 is connected to the computer 800 via, for example, a display cable.

  Each embodiment described above is for facilitating understanding of the present invention, and is not intended to limit the present invention. The present invention can be changed / improved without departing from the spirit thereof, and the present invention includes equivalents thereof. Each embodiment is an exemplification, and it is needless to say that a partial replacement or combination of configurations shown in different embodiments is possible, and these are also included in the scope of the present invention as long as they include the features of the present invention. . For example, when digital broadcasting is charged, the ECM sensor 80 may acquire data to be output from the CAS unit 702 to the control unit 701. This makes it possible to determine whether or not the user of the target receiver 30 is a pay broadcast contractor.

1 channel determination system, 10 channel determination device, 20 broadcasting station system, 30 target receiver, 40 reference receiver, 70 TV, 80 sensor, 101 acquisition unit, 102 extraction unit, 103 comparison unit, 201 scramble unit, 202 ECM generation , 203 Multiplexer, 701 Controller, 702 CAS Unit

Claims (9)

From the target receiver configured to be capable of receiving a broadcast stream including digital broadcast content encrypted with a different scramble key for each channel and information on the scramble key related to the content encryption, the target receiver A first acquisition unit that acquires target data, which is information about ECM data included in the received broadcast stream or a scramble key included in the ECM data;
A reference data that is information related to ECM data included in the broadcast stream received by the reference receiver or a scramble key included in the ECM data is acquired from a reference receiver configured to be able to receive the broadcast stream. An acquisition unit;
A channel corresponding to the broadcast stream received at the target receiver is determined based on information on a channel corresponding to the broadcast stream received at the reference receiver and whether or not the target data matches the reference data. A determination unit to perform,
A channel determination device comprising: The ECM data or the scramble key included in the ECM data is updated at a predetermined cycle for each channel.
The channel determination apparatus according to claim 1. The first acquisition unit or the second acquisition unit is
Obtaining the target data or the reference data in synchronization with each other so that the target data and the reference data include ECM data generated at the same timing or information on a scramble key included in the ECM data;
The channel determination apparatus according to claim 2. The information on the scramble key included in the broadcast stream includes a scramble key encrypted with a work key in the system that transmits the broadcast stream.
The channel determination apparatus in any one of Claims 1-3. The second acquisition unit includes
Obtaining the reference data from each of the plurality of reference receivers receiving broadcast streams of different channels;
The determination unit
Comparing the target data with each of the plurality of reference data to determine which reference data the target data matches;
The channel determination apparatus in any one of Claims 1-4. The reference receiver switches a channel corresponding to a broadcast stream received at a predetermined period,
The determination unit
Determining at which timing the target data matches the reference data acquired;
The channel determination apparatus in any one of Claims 1-4. From the target receiver configured to be capable of receiving a broadcast stream including digital broadcast content encrypted with a different scramble key for each channel and information on the scramble key related to the content encryption, the target receiver A first acquisition unit that acquires target data, which is information about ECM data included in the received broadcast stream or a scramble key included in the ECM data;
A reference data that is information related to ECM data included in the broadcast stream received by the reference receiver or a scramble key included in the ECM data is acquired from a reference receiver configured to be able to receive the broadcast stream. An acquisition unit;
A channel corresponding to the broadcast stream received at the target receiver is determined based on information on a channel corresponding to the broadcast stream received at the reference receiver and whether or not the target data matches the reference data. A determination unit to perform,
A channel determination device comprising:
A first sensor configured to be connectable to the target receiver and transmitting information on the target data to the first acquisition unit;
A second sensor configured to be connectable to the reference receiver and transmitting information on the reference data to the second acquisition unit;
Channel judgment system. Computer
From the target receiver configured to be capable of receiving a broadcast stream including digital broadcast content encrypted with a different scramble key for each channel and information on the scramble key related to the content encryption, the target receiver Obtaining target data, which is information about the ECM data included in the received broadcast stream or the scramble key included in the ECM data;
Obtaining reference data, which is information related to ECM data included in the broadcast stream received by the reference receiver or a scramble key included in the ECM data, from a reference receiver configured to be able to receive the broadcast stream; ,
A channel corresponding to the broadcast stream received at the target receiver is determined based on information on a channel corresponding to the broadcast stream received at the reference receiver and whether or not the target data matches the reference data. And steps to
Execute the channel judgment method. Computer
From the target receiver configured to be capable of receiving a broadcast stream including digital broadcast content encrypted with a different scramble key for each channel and information on the scramble key related to the content encryption, the target receiver Means for obtaining target data, which is ECM data included in the received broadcast stream or information relating to a scramble key included in the ECM data;
Means for obtaining, from a reference receiver configured to be able to receive the broadcast stream, reference data that is ECM data included in the broadcast stream received by the reference receiver or information relating to a scramble key included in the ECM data; And the channel corresponding to the broadcast stream received at the target receiver based on the information on the channel corresponding to the broadcast stream received at the reference receiver and whether or not the target data matches the reference data. Means for determining,
Program to function as.