CN102014306B

CN102014306B - Method for simultaneously deciphering multiple charge programs by set-top box

Info

Publication number: CN102014306B
Application number: CN2010105058138A
Authority: CN
Inventors: 彭毅弘
Original assignee: Fujian Newland Communication Science Technology Co Ltd
Current assignee: Fujian Newland Communication Science Technology Co Ltd
Priority date: 2010-10-13
Filing date: 2010-10-13
Publication date: 2012-06-20
Anticipated expiration: 2030-10-13
Also published as: CN102014306A

Abstract

The invention provides a method for simultaneously deciphering multiple charge programs by a set-top box, comprising the following steps of: utilizing each PMT (Program Management Information) table extracting a needed program; re-analyzing the PMT tables of the multiple enciphering programs to be combined into one PMT table to be re-transmitted to a CAS (Conditional Access System); and providing cipher key data to the set-top box by the CAS so as to decipher the multiple charge programs. The invention overcomes the defect that the CAS cannot simultaneously analyze a plurality of PMT tables and realizes the condition that the multiple charge programs are simultaneously deciphered by the set-top box, therefore, the requirement on a user for watching a plurality of encryption programs at the same time is satisfied.

Description

A kind of STB of realizing is deciphered the method for many cover charge programs simultaneously

[technical field]

The present invention relates to a kind of technical field of digital television set-top, especially relate to a kind of STB of realizing and decipher the method for many cover charge programs simultaneously.

[background technology]

As the guide and the core of digitized home, DTV has been come into our life.Along with the realization of the integration of three networks, the role of DTV not merely is a broadcast reception platform, and it has developed into the Multi-media Service Platform of integrating various family information resources.The user uses STB except watching TV programme, can also browsing page, and inquiry quotations on the stock market etc.Broadcast the headend equipment of program; Can be inserted into value added data such as stock certificate data or ad data in the middle of the same frequency with the related video frequency program of these data as a programs, can encrypt the video frequency program and the value added data program of needs charge simultaneously.If the user when checking the value added data program of encryption, need watch the video frequency program of encryption, then terminal set top box just must be deciphered the multiple enciphered data that belongs to different programs simultaneously.The program decryption of STB all is to analyze enciphered message through obtaining PMT (program information), deciphers program thereby obtain key.Each program all has a PMT, and a plurality of programs just have a plurality of PMT, if decipher the data of a plurality of programs simultaneously, condition receiving and deciphering module just must possess the function of analyzing many PMT simultaneously.But the CAS of main flow (condition receiving system module) at one time can only PMT of analyzing and processing in the market, the enciphered data that promptly can only decipher a programs.When for example checking quotations on the stock market, but can not on screen, watch finance and economics video frequency program, the present invention simultaneously is exactly in order to satisfy the user when watching video frequency program, also to check the value added data program.

[summary of the invention]

The technical problem that the present invention will solve is to provide a kind of STB of realizing to decipher the methods of many cover charge programs simultaneously, realized that STB deciphers multiple programs simultaneously, thereby has satisfied the requirement that the user can watch a plurality of ciphered programs simultaneously.

The present invention is achieved in that a kind of STB of realizing deciphers the methods of many cover charge programs simultaneously, it is characterized in that: may further comprise the steps:

Step 10, user select a certain program, STB be tuned to corresponding program frequency point, catch the pmt table information of each road program of described program frequency point through the PMT identification information that Broadcast and Television Center is sent, and be stored in the memory headroom of STB;

Step 20, STB start the programme information filter; Extract the pmt table information of required programs;

Descriptor in the first round for circulation of step 30, every pmt table of extraction is merged into first round for looping discription symbol of another pmt table in order with it; Extract second of described every pmt table and take turns basic stream looping discription symbol, merge to second of described another pmt table and take turns in the basic stream looping discription symbol; And revise the described byte number of program_info_length field in described another pmt table;

Described another pmt table data of the CAS module analysis of step 40, STB, PID Packet Identifier PID number of ECM code stream of obtaining the enciphered data of each program starts the section filter according to PID Packet Identifier PID number of ECM code stream, obtains the ECM data;

Step 50, obtain PID Packet Identifier PID number of EMM (Entitlement Management Message) code stream according to the CAT in program table (CAT Conditional Access Table) and start the section filter, obtain the EMM data;

Step 60, give the CAS module analysis with ECM and EMM returning data, communicate with smart card of set-top box simultaneously, whether judges has the program of paying and buying, and is that then the CAS module provides key data to STB, otherwise does not provide;

Step 70, do not receive key data, the charge program is not deciphered, and receives key data, and STB sends key data to descrambler, accomplishes the deciphering of many cover charge programs.

The present invention has following advantage: extract each pmt table of required programs, and the pmt table that will overlap ciphered program reanalyses and be combined into a pmt table and return to CAS more, decrypt the charge programs that overlap more.The invention solves CAS and can't analyze the shortcoming of a plurality of PMT simultaneously, realized that STB deciphers multiple programs simultaneously, thereby satisfied the requirement that the user can watch a plurality of ciphered programs simultaneously.

[description of drawings]

Fig. 1 realizes deciphering simultaneously the method flow sketch map of multiple programs for STB.

[embodiment]

Combine embodiment that the present invention is further described with reference to Fig. 1 below:

A kind of STB of realizing is deciphered the method for many cover charge programs simultaneously, may further comprise the steps:

Step 10, user select a certain program; STB be tuned to corresponding program frequency point, catch the pmt table information of each road program of described program frequency point through the PMT identification information that Broadcast and Television Center is sent, and be stored in the memory headroom of STB; Can comprise multiple descriptor in the pmt table; Like CA_descriptor, stream_identifier_descriptor etc., as for which descriptor is specifically arranged, often need analyze actual code stream could determine.The header of PMT section partly is 8 bytes, forms by table identifier (to be different from other tables), section length, program number, version number, section number, last section number;

Step 20, STB start the programme information filter, extract the pmt table information of required programs;

Descriptor (the descriptor that comprises in first for loop body of pmt table of the first round for loop body of step 30, every pmt table of extraction; What this took turns that the loop body descriptor describes is all relevant informations that flow basically of this program), it is merged in the descriptor of first round loop body of another pmt table in order; Extract second of described every pmt table and take turns the descriptor of basic stream loop body (descriptor content during second for circulates in the pmt table), merge to second of described another pmt table and take turns in the descriptor of basic stream loop body; And revise the described byte number of program_info_length field in described another pmt table;

Described another pmt table data of the CAS module analysis of step 40, STB, PID number of ECM code stream of obtaining the enciphered data of each program starts the section filter according to PID number of ECM code stream, obtains the ECM data;

Step 50, obtain PID number of EMM code stream according to the CAT in program table and start the section filter, obtain the EMM data;

Step 60, give the CAS module analysis with ECM and EMM returning data, communicate with smart card of set-top box simultaneously, whether judges has the video frequency program and the value added data program of charge, is that then the CAS module provides key data to STB, otherwise does not provide;

Wherein for the STB of single tuner (tuning), the user can only watch a cover video frequency program at one time.The Polymera here is meant a cover video frequency program and a value added data program.At present most typical is exactly that the quotations on the stock market of charge and the same screen of finance and economics program of charge are watched, and perhaps the same screen of the broadcast video programs of the web page browsing of charge and charge occurs.

For the STB of two tuner, the user can watch two cover video frequency programs, promptly traditional picture-in-picture simultaneously.The Polymera here is meant at two cover video frequency program and value added data programs.

In a word, the present invention adopts each pmt table that extracts required programs, and the pmt table that will overlap ciphered program reanalyses and be combined into another pmt table and return to CAS more, and CAS provides key data to STB, thereby decrypts the charge programs that overlap more.

The above is merely preferred embodiment of the present invention, and all equalizations of doing according to claim of the present invention change and modify, and all should belong to covering scope of the present invention.

Claims

1. realize that STB deciphers the methods of many cover charge programs simultaneously for one kind, it is characterized in that: may further comprise the steps:

Step 50, receive the CAT table according to the condition in the program and obtain PID Packet Identifier PID number of EMM code stream and start the section filter, obtain the EMM data;

2. a kind of STB of realizing according to claim 1 is deciphered the method for many cover charge programs simultaneously, and it is characterized in that: the program that the paying described in the step 60 is bought comprises the video frequency program and the value added data program of charge.