CN102098575A - Migration method compatible with multiple conditional access (CA) systems and CA method - Google Patents

Abstract

The invention discloses a transplantation method compatible with multiple conditional access systems and a conditional access method. The method for described transplantation comprises the following steps: in the set-top box program, several kinds of conditional access systems are built-in, according to the function setting general interface function of the interface that all conditional access systems will transplant, provide to the set-top box application program; Judge the condition that current smart card belongs to The type of the receiving system, calling the general interface function to initialize the modules required by the conditional access system corresponding to the current smart card; setting the general data structure, converting the data output by different conditional access systems into a general data structure, and providing it to Set-top box application. By using the transplanting method of the invention, the compatibility of CA system transplantation can be improved, the software development process at the set-top box end can be simplified, and the cross-platform transplantation speed can be improved.

Description

Compatible with multiple conditional access system porting methods and conditional access methods

technical field

The invention relates to computer technology, in particular to a method and a conditional access method capable of transplanting compatible multiple conditional access systems, and belongs to the technical field of digital television.

Background technique

The conditional access (CA) system is used to digitally scramble and encrypt the content of digital TV programs to establish an effective charging system. It is called the technical guarantee system for the healthy development of digital TV. At the front end, the CA system mainly completes the acquisition, generation, encryption, and transmission of user authorization control messages (ECM) and user authorization management messages (EMM); at the receiving end, it receives and processes the ECM and EMM information sent by the front-end CA system, and decodes them. Output the control word (CW), and descramble the audio and video stream according to the control word to realize the playback of audio and video.

In order for the set-top box to descramble the audio and video stream of the program, it is necessary to transplant the CA system kernel into the set-top box. The CA transplantation process is based on the library provided by the manufacturer as the core, using the CA core to implement the bottom interface, and providing a unified function interface for the set-top box application program. At present, there are many CA systems from different manufacturers, such as Yongxin Shibo, Digital Video, Sutong, Tianbai, etc. The implementation methods of the CA underlying function interfaces of different manufacturers are not the same. When transplanting a CA system in a set-top box, it is necessary to perform corresponding transplantation according to the transplantation documents of each CA system. Each CA system corresponds to a set of set-top box application software. Therefore, only one CA system can be implemented in a set-top box. Moreover, if you want to implement the CA system of another manufacturer in the set-top box of the same platform, or implement the CA system of the same manufacturer in the set-top boxes of different platforms, due to the inconsistency of the underlying functions, it cannot be directly transplanted, and a set of applications needs to be redeveloped. Software consumes a lot of time and energy for software developers, and the transplantation time is relatively long.

On the other hand, when transplanting a single CA system in the prior art, only the data of this system is considered when implementing functions such as authorization, email, fingerprint, IPPV (instant video on demand), IPPT (instant pay on demand) and other functions structure, so that the set-top box application needs to be processed separately by using different software for each CA system, which reduces the speed of transplanting the CA system and is not conducive to the improvement of the compatibility of the CA system transplantation.

Contents of the invention

One of the purposes of the present invention is to provide a method for transplanting compatible multiple conditional access systems, so as to improve the compatibility of CA system transplantation, simplify the software development process at the set-top box end, and increase the speed of cross-platform transplantation.

In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions to achieve:

A method for transplanting compatible multiple conditional access systems, said method comprising the steps of:

a1. Several conditional access systems are built in the set-top box program, and the general interface functions are set according to the functions of the interfaces to be transplanted by all conditional access systems, and provided to the set-top box application program;

a2. Determine the type of the conditional access system to which the current smart card belongs, and call the general interface function to initialize the modules required by the conditional access system corresponding to the current smart card;

a3. Setting a common data structure, converting the data output by different conditional access systems into a common data structure, and providing it to the set-top box application program.

As described above, the method for transplanting compatible multiple conditional access systems, specifically, the general interface function is an interface function that is common to multiple CA systems, including an OS adaptation layer interface function and a communication interface function for communicating with a smart card , demultiplexing interface function and data storage interface function.

The method for transplanting compatible multiple conditional access systems as described above, in order to avoid occupation of the common interface resources of the set-top box and provide resource utilization, the general interface function also includes a release interface function for releasing the conditional access system function, through the release interface Functions can release the resources they occupy when exiting the conditional access system.

As described above, in the method for transplanting compatible multiple CA systems, in the step a2, the type of CA system to which the current smart card belongs can be determined according to the card transmission protocol and the card identification of the current smart card.

The method for transplanting compatible multiple conditional access systems as described above, in the step a2, the initialization of the conditional access system corresponding to the current smart card includes OS adaptation layer initialization, communication interface initialization, demultiplexing initialization and storage initialization.

The second object of the present invention is to provide a conditional access method, which is based on the above-mentioned method for transplanting compatible multiple conditional access systems, and can realize the descrambling of digital TV programs at the set-top box end with multiple conditional access systems transplanted and authorization management.

In order to realize the above-mentioned purpose of the invention, the present invention adopts following technical scheme to realize:

A conditional access method, said method comprising the steps of:

b1. The set-top box application triggers the conditional access, and calls the general interface function to initialize the conditional access system;

b2. Call the general interface function to obtain authorization control information and authorization management information from the TS stream, and transmit it to the smart card corresponding to the conditional access system through the general interface function for decryption processing;

b3. Provide the decrypted scrambling control word to the descrambler through the general interface function, and descramble the encrypted audio and video stream;

b4. Convert the decrypted other authorization control information data and authorization management information data into a common data structure, and provide it to the set-top box application program.

In the above-mentioned conditional access method, in order to ensure the integrity of data and avoid data loss, in the step b2, after calling the general interface function to obtain the authorization control information and authorization management information from the TS stream, it is first cached, and then the complete The authorization control information and authorization management information are transmitted to the smart card corresponding to the conditional access system through the general interface function for decryption.

In the above-mentioned conditional access system, in order to facilitate the use of the application program, in the step b4, the decrypted authorization management information data is converted into a general data structure, and provided to the set-top box application program in the form of a callback function or a message.

In the above-mentioned conditional access system, in the step b1, the set-top box application program that triggers conditional access includes a program for users to switch channels during program playing, a program for users to switch frequency points, and a program for monitoring front-end service information data version changes at least one of the programs.

The above conditional access system is characterized in that, in the step b1, the initialization of the conditional access system by calling the general interface function includes OS adaptation layer initialization, communication interface initialization, demultiplexing initialization and memory initialization.

Compared with the prior art, the advantages and positive effects of the present invention are: the present invention has the characteristics of some functionally identical interface calls when CA systems of different manufacturers are transplanted on the set-top box, multiple conditional access systems are built in the set-top box, and According to the function of the interface to be transplanted by all conditional access systems, the general interface function is set as a unified external standard interface function; at the same time, the general data structure is set, and the decrypted data output by different conditional access systems are respectively converted into a general data structure, Utilize the related unified interface function and the unified general data structure to facilitate the transplantation of the conditional access system, and can be compatible with many different conditional access systems at the same time, which simplifies the software development process of the set-top box side, speeds up the development speed of the application software, and improves the The speed of cross-platform transplantation improves the speed and efficiency of conditional access system to extract private data, and it is convenient and simple to use.

Other characteristics and advantages of the present invention will become clearer after reading the detailed description of the present invention in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is the flow chart of an embodiment of the method for the transplantation of multiple conditional access systems compatible with the present invention;

Fig. 2 is a flowchart of an embodiment of the conditional access method of the present invention.

Detailed ways

The technical solutions of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

The present invention aims at the inability to realize the compatibility of the conditional access system transplantation of different manufacturer types when the existing conditional access system is transplanted by using its own interface library to define the interface and process, the development of the set-top box application program takes more time, and the resource sharing is relatively poor. Considering that although different conditional access systems have different bottom interface implementation methods, but the implementation functions have many common characteristics for set-top box applications, a method of transplanting compatible with multiple conditional access systems is proposed. Set relevant unified interface functions and unified general data structure, manage resources in a unified way, facilitate the transplantation of conditional access systems, can be compatible with many different conditional access systems at the same time, simplify the software development process of the set-top box end, and improve the speed of cross-platform transplantation .

FIG. 1 shows a flow chart of an embodiment of the method for transplanting compatible multiple conditional access systems of the present invention. As shown in Figure 1, the specific implementation process of this embodiment is as follows:

S11: Several conditional access systems are built into the set-top box program, and a general interface function is set according to the interface functions to be transplanted by all conditional access systems, and provided to the set-top box application program.

When almost all conditional access systems are ported to set-top boxes, they stipulate the storage data interface, receiving data interface, memory, message and other processing interfaces required for the operation of the conditional access system kernel, and the interface for communicating with smart cards. The functions are the same, and there is no big difference in the corresponding program itself. Therefore, in order to realize the compatibility of the application program with various conditional access systems, the OS adaptation layer interface function, the communication interface function for communicating with the smart card, the demultiplexing interface function and the data storage interface function are set as general interface functions, as The standard interface functions transplanted by the conditional access system are provided to the set-top box application program.

In addition, in order to avoid the occupation of common interface resources of the set-top box and improve resource utilization, the general interface function also includes a release interface function that releases the conditional access system function. Through this release interface function, the occupied user can be released when the user exits the conditional access system. resource.

S12: Determine the type of the conditional access system to which the current smart card belongs, and call the general interface function to initialize the modules required by the conditional access system corresponding to the current smart card.

There are multiple conditional access systems built in the set-top box, but only one smart card can be used in each set-top box to realize one conditional access system. Therefore, according to the type of the conditional access system to which the current smart card belongs, it is necessary to call the general interface function to initialize the relevant functional modules required by the conditional access system corresponding to the current smart card.

Wherein, when judging the type of the conditional access system to which the current smart card belongs, it can be judged according to the card transmission protocol and the card identification of the current smart card. The set-top box system resets the inserted smart card, obtains the card transmission protocol type, and obtains the card identification according to the data returned by the reset, so that it can determine which CA system the smart card belongs to.

After determining the type of conditional access system to which the current smart card belongs, the set-top box system will automatically call the general interface function to initialize the functional modules corresponding to the conditional access system, including smart card initialization, OS adaptation layer initialization, communication interface initialization, and demultiplexing. Initial settings such as initialization and memory initialization.

S13: Setting a common data structure, converting the data output by different CA systems into a common data structure, and providing it to the set-top box application program.

When different conditional access systems implement authorization, mail, fingerprint, IPPV, IPPT and other related applications, the authorization management information data output after decryption processing adopts its own data structure, which is not easy to be compatible with multiple conditional access systems Therefore, the conditional access system transplantation method of this embodiment has set a common data structure, and the data that different conditional access systems output are all converted into the application program that this common data structure form is provided to the set-top box, facilitates the application program use.

By defining the above general interface function and general data structure, the STB resources are managed uniformly, which facilitates the transplantation of different conditional access systems and realizes compatibility.

The method for realizing conditional access in the set-top box compatible with multiple conditional access systems is shown in the embodiment of Figure 2, the conditional access method of this embodiment is based on the method for transplanting compatible multiple conditional access systems of Figure 1, and its specific process is as follows:

S21: The set-top box application program triggers the conditional access, and calls the general interface function to initialize the conditional access system.

In this embodiment, the set-top box application that triggers conditional access may be a program for users to switch channels during program playing, or a program for users to switch frequency points, or a program for monitoring changes in front-end service information data versions, wherein, The change of the front-end service information data version mainly means that the data of the program management table PMT and the conditional access table CAT have changed. As long as one of the programs satisfies the trigger condition, a conditional access request can be issued to trigger conditional access. After the conditional access is triggered, the application program will call the general interface function to initialize the conditional access system. For the general interface function and initialization settings, refer to the description in FIG. 1 above.

S22: Call the general interface function to obtain authorization control information and authorization management information from the TS stream and cache them.

Here, it is mainly to call the demultiplexing interface function to filter the TS stream sent by the front end, and obtain corresponding entitlement control information (ECM) and entitlement management information (EMM). Specifically, the set-top box obtains the PID values of EMM and ECM according to the CA description of the PMT and CAT tables, and then filters out the ECM and EMM from the TS stream according to the PID values. For ECM and EMM data with multiple slots, in order to avoid data loss, after extracting the data of a slot in the background, first configure the cache queue to cache the extracted ECM and EMM data.

S23: Determine whether the ECM and EMM data have been acquired. If the acquisition is completed, execute step S24; if not, go to step S22 to continue acquisition.

S24: After the ECM and EMM data are obtained, transmit the complete ECM and EMM data in the cache to the smart card corresponding to the conditional access system for decryption processing through the general interface function.

The decryption process of the smart card is as follows: the smart card reads the user's personal distribution key PDK stored in it, uses the PDK to decrypt the EMM, and takes out the service key SK; then, uses the SK to decrypt the ECM to get the scrambled control word CW. At the same time, the decryption process can also obtain the address contained in the EMM, user authorization information, such as the programs or time periods that the user can watch, and the viewing fees paid by the user, so as to realize related authorization management.

S25: Provide the decrypted scrambled control word to the descrambler through the general interface function to descramble the encrypted audio and video stream.

S26: Convert other authorized control information data and authorized management information data after decryption processing, such as program information data such as program source, time, content classification and program price, email, fingerprint and other data into a general data structure, and provide it to the set-top box application program . Here, other authorization control information data refers to other information data after ECM decryption except scrambling control words. These data include program information data such as program source, time, content classification and program price, etc., which need to be provided to the set-top box application program. . In the authorized management information data EMM, it not only includes management information data such as emails and fingerprints, but may also contain program information data such as source, time, and content classification of on-demand programs such as IPPV and IPPT. These data also need to be provided to the set-top box. application use.

In this embodiment, in order to facilitate the use of application programs and realize the real-time and rapid distribution of data, the data after descrambling is converted into a general data structure, which is provided to the set-top box application program in the form of callback function or message, and the descrambling and processing of digital TV is completed. Related functions such as authorization management.

The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art can still understand the foregoing embodiments. Modifications are made to the technical solutions described, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions claimed in the present invention.

Claims (10)

1. A method for compatible multiple conditional access system transplantation, characterized in that, said method may further comprise the steps: a1. Several conditional access systems are built in the set-top box program, and the general interface functions are set according to the functions of the interfaces to be transplanted by all conditional access systems, and provided to the set-top box application program; a2. Determine the type of the conditional access system to which the current smart card belongs, and call the general interface function to initialize the modules required by the conditional access system corresponding to the current smart card; a3. Setting a common data structure, converting the data output by different conditional access systems into a common data structure, and providing it to the set-top box application program. 2. the method for compatible multiple conditional access system transplantation according to claim 1, is characterized in that, described general interface function comprises OS adaptation layer interface function, the communication interface function that communicates with smart card, demultiplexing interface function and data storage interface functions. 3 . The method for transplanting compatible with multiple conditional access systems according to claim 2 , wherein the general interface function further includes a release interface function for releasing conditional access system functions. 4 . 4. The method for transplanting compatible multiple conditional access systems according to any one of claims 1 to 3, characterized in that, in said step a2, it is judged according to the card transmission protocol and card identification of the current smart card that the current smart card belongs to The type of conditional access system. 5. the method for compatible multiple conditional access system transplantation according to claim 4, is characterized in that, in described step a2, the initialization that the conditional access system corresponding to current smart card is carried out comprises OS adaptation layer initialization, Communication interface initialization, demultiplexing initialization and memory initialization. 6. A conditional access method, the method is based on the method for transplanting compatible multiple conditional access systems according to claim 1, wherein the conditional access method comprises the following steps: b1. The set-top box application triggers the conditional access, and calls the general interface function to initialize the conditional access system; b2. Call the general interface function to obtain authorization control information and authorization management information from the TS stream, and transmit it to the smart card corresponding to the conditional access system through the general interface function for decryption processing; b3. Provide the decrypted scrambling control word to the descrambler through the general interface function, and descramble the encrypted audio and video stream; b4. Convert the decrypted other authorization control information data and authorization management information data into a common data structure, and provide it to the set-top box application program. 7. The conditional access method according to claim 6, characterized in that, in said step b2, after the general interface function is called to obtain the authorization control information and authorization management information from the TS stream, it is cached first, and then the complete authorization The control information and authorization management information are transmitted to the smart card corresponding to the conditional access system through the general interface function for decryption. 8. The conditional access system according to claim 6 or 7, characterized in that, in the step b4, the decrypted authorization management information data is converted into a general data structure, and provided to the set-top box in a callback function mode or a message mode application. 9. The conditional access system according to claim 8, characterized in that, in said step b1, the set-top box application program that triggers conditional access includes a program for users to switch channels and a program for users to switch frequency points during program playing And at least one of the programs for monitoring the version change of the front-end business information data. 10. The conditional access system according to claim 9, characterized in that, in the step b1, calling the general interface function to initialize the conditional access system includes OS adaptation layer initialization, communication interface initialization, demultiplexing initialization and memory initialization.

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