KR20090095777A - Method and apparatus for output conditional access system broadcasting program in digital broadcasting system - Google Patents

Abstract

A method and an apparatus for outputting a conditional access system broadcasting program in a digital broadcasting receiver are provided to change a CAS(Conditional Access System) freely without opening software among enterprises, thereby improving a selection right of a user. An MPEG(Moving Picture Experts Group) decoder(108) decodes a TS(Transport Stream). The MPEG decoder outputs the decoded transport stream by audio/video signals. In a memory(112), specific conditional access system software of a digital broadcasting receiver is mounted. A controller(110) manages interface and software setting of at least two conditional access systems. The controller selectively replaces the mounted conditional access system software.

Description

Conditional access system broadcast program output method and apparatus in a digital broadcasting receiver TECHNICAL AND APPARATUS FOR OUTPUT CONDITIONAL ACCESS SYSTEM BROADCASTING PROGRAM IN DIGITAL BROADCASTING SYSTEM

The present invention relates to a conditional access system (hereinafter referred to as CAS) in a digital broadcast receiver, and in particular, a method for outputting a CAS broadcast program in a digital broadcast receiver suitable for selectively applying a plurality of CAS software. Relates to a device.

Recently, with the development of digital technologies such as digital image compression and digital modulation / demodulation, the standardization and commercialization of digital television broadcasting is rapidly progressing. Also, in the conventional terrestrial, satellite, and cable broadcasting, MPEG (Moving Picture Experts Group) Based on this trend, digitalization is on the rise.

In digital broadcasting, a plurality of broadcast programs encoded based on MPEG are multiplexed and transmitted in the form of a transport stream (hereinafter referred to as TS), which is a digital receiver such as a set-top box (STB) installed at a receiving side. A plurality of broadcast programs received by the broadcast receiver and included in the TS are demultiplexed.

Therefore, only one broadcast program desired by a user can be selected. Also, in a digital broadcast receiver such as a set-top box, a general television after restoring the selected broadcast program to an original audio and video signal using an MPEG decoder included in the receiver. It transmits to A / V output device such as

Such digital broadcasting is gradually being activated due to the commercial advantages of broadcasting a much wider range of channels than analog channels, and various functions such as high image quality, sound, interactive services, and internet access.

Accordingly, the digital set-top box industry is growing mainly in the United States and Europe, and is showing high growth in the Middle East and Asia due to the introduction of the digital broadcasting.

Digital broadcasting is mainly led by pay-TV operators, and the set-top box market is directly purchased by pay-TV businesses. In terms of technology, digital set-top boxes are designed to digitally code analog content at the broadcasting station so that the broadcast signal can be viewed on a regular TV through a satellite or cable ground. .

However, since the above process requires complicated processing, a technical problem may be raised in order for a broadcaster to supply various broadcast services. This is a matter of broadcasting standards, and the standards currently adopted by the world's largest broadcasters are the European standard DVB (Digital Video Broadcasting) or the US Direct Dict TV's own DSS (Digital Satellite Service). Various criteria are defined.

In addition, TS, which restricts reception so that only subscribers can receive in pay broadcasting, that is, CAS which conditionally accesses digital satellite broadcasting signals, is also currently competed by 10 companies such as Media-Guard, NDS, and viaccess. have.

Such CAS refers to a conditional access device for a digital satellite broadcasting set top box, and is responsible for a paid reception function of digital satellite broadcasting.

Here, in order to transmit and receive only a specific satellite broadcast signal, that is, to protect digital broadcast content, MPEG packets may be scrambled and transmitted for a specific satellite broadcast signal, and descrambled by the receiver so that the viewer can view the broadcast content. Will be.

This descrambling function is accomplished through a card-shaped "CAM" (conditional access module), and these cams are connected to a common interface module (hereinafter referred to as CI) and are first encrypted via a satellite broadcast signal. The contents are decoded and then broadcast contents finally transmitted through a demultiplexer, an MPEG decoder, etc. are displayed to the user.

Here, the cam is a pay broadcasting module which is inserted (or connected) into the set-top box of the digital broadcasting system, and more specifically, the PCMCIA of the CI module. The cam is intercepted and decoded from the tuner to the chip. The module to execute. That is, as described above, when the pay TV signal is transmitted in the digital broadcasting system, a scrambling operation is performed in which the frequency is intentionally changed so that the TV cannot be viewed, and the cam descrambles the scrambled broadcast signal. To act on the set-top box.

Cams are classified into various types according to the method of scrambling broadcast signals. For example, cams are designed according to viases, nagravision, conax, and cryptoworks. Each method is not compatible with each other. In order to eliminate such incompatibility, the set-top box is equipped with a cam externally, and the CI is defined between the cam and the set-top box. Accordingly, the viewer only needs to connect a smart card provided by the broadcaster to the cam, and does not need to separately consider the scrambling method of the cam.

On the other hand, existing CAS software, such as CAS software such as "NDS" or "Irdeto", has a feature that, once mounted in a digital broadcast receiver, cannot be modified later and must be viewed continuously.

That is, since the first CAS software descrambles only the specific broadcast program, the second scrambled broadcast program cannot be viewed.

Of course, the CI descrambling method as described above is implemented and used to compensate for the above-mentioned disadvantages, but this is not only costly in producing a digital broadcasting receiver, but also from the user's point of view, CAM and smart-card. There is a hassle to purchase separately.

Accordingly, the present invention provides a conditional access system broadcast program output method in a digital broadcast receiver capable of selectively replacing CAM software descrambling a specific broadcast program so that a plurality of CAM broadcast programs can be output from one digital broadcast receiver. To provide.

According to an aspect of the present invention, there is provided a conditional access system broadcast program output apparatus of a digital broadcasting receiver, comprising: an MPEG decoder for decoding a descrambled transport stream through the conditional access system and outputting the decoded transport stream as an audio / video signal; And a control unit configured to manage a memory in which specific conditional access system software of the digital broadcasting receiver is mounted, and to manage interface and software settings of at least two conditional access system to selectively replace conditional access system software mounted in the memory. A conditional access system broadcast program output device in a digital broadcast receiver is provided.

According to another aspect of the present invention, when a first conditional access system broadcast program of the first conditional access system software is output through a digital broadcast receiver, a change to the second conditional access system broadcast program is requested. Determining a user interface; if a change to the second conditional access system broadcast program is requested, checking user information; opening a specific download channel; downloading the second conditional access system software; and an interface region. Replacing the first conditional access system software with the second conditional access system software through the second conditional access system software, and descrambles the second conditional access system broadcast program by driving the replaced second conditional access system software. Provided is a conditional access system broadcast program output method in a digital broadcast receiver comprising the step of outputting a sound access system broadcast program.

According to the present invention, it is possible to eliminate the disadvantage of having to use only one CAS continuously, as in the case of the existing CAS, and increase the user's choice by changing the CAS freely without the release of the software among the respective companies. There is an advantage that you can watch.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a block diagram illustrating an apparatus for outputting a CAM broadcast program in a digital broadcast receiver according to an aspect of the present invention, and includes a tuner 100, a demodulator 102, a CAS 104, a demux 106, and an MPEG decoder. 108, a control unit 110, and a memory unit 112.

As shown in FIG. 1, the tuner 100 frequency-tunes a TS received through an external satellite, and the demodulator 102 demodulates the TS tuned by the tuner 100 to receive a broadcast stream signal originally transmitted. It serves to detect. In this case, the received TS is scrambled in a predetermined manner, and the TS passing through the tuner 100 and the demodulator 102 is also maintained in the scrambled state.

As such, the TS passing through the tuner 100 and the demodulator 102 is descrambled via the CAS 104, and then synthesized as a single channel in the multiplexer of the original broadcasting station by the demultiplexer (DEMUX) 106. The digital broadcast stream which is separated and also separated by the demultiplexer 106 is decompressed by the MPEG decoder 108 so that the digital broadcast stream, that is, the broadcast content firstly transmitted, is output to the user as an audio / video signal. Will be.

In this case, the CAS 104 is a system for granting or restricting the right to view an encrypted broadcast, demodulating the TS received through the satellite through the tuner 100 and the demodulator 102 and then generating the TS. Parses the PMT (Program Map Table) in the table and extracts values related to CAS. Here, the PMT includes basic information of a program, and this value is separated from PSI (Program Specific Information), and then a CAS-related value is extracted through the separated value.

In general, CAS-related values are delivered through an Entitlement Control Message (ECM) value. The CW (Control Word) value is called from these values, and then the descrambling process is set up through this CW value.

Meanwhile, the controller 110 manages the interface and software settings of the CAS 104 to selectively replace CAM software that descrambles a specific broadcast program. That is, the CAS software in the CAS 104 serves to descramble one specific broadcast program. In this embodiment, a plurality of CAS software are selectively allocated to the memory unit 112 to be described later to output different broadcast programs. Make it possible.

To this end, the controller 110 must share at least two CAS interface regions, that is, name-space regions. If A CAS software is installed as a default and a user wants to change to B CAS software, the basic variables and functions of CAS software should be compatible. To implement this, it is necessary for A CAS and B CAS to share only the CAS interface area in advance. That is, the present embodiment provides an environment in which a namespace area is separately set and a plurality of CAS interface areas can be shared in the namespace area. Since only the CAS interface area is shared, CAS software can be changed even if the actual CAS software is not installed in the digital broadcasting receiver. In the case of a general flash memory, the software can be updated except for a boot loader. The boot loader is a core program required for initial operation in a digital broadcasting receiver or other set-top box. The boot loader stores basic settings in the boot loader and the write function cannot be applied in any case. Except for the boot loader, the remaining memory area can be allocated to store specific values.

In this embodiment, focusing on the above, it is intended to replace the software of A CAS and B CAS. In other words, except for the boot loader, which is the lowest level of the memory area, the memory area (address) immediately above can be designated as a CAS area, and at least two CAS interface areas can be shared to selectively replace CAS software. It features.

On the other hand, the memory unit 112 is a flash memory, for example, is equipped with a particular CAS software except for the boot loader in the digital broadcast receiver, the control unit 110 changes to any CAS software For example, A CAS software can be replaced with B CAS software.

Hereinafter, the CAM broadcast program output process in the digital broadcast receiver according to another aspect of the present invention together with the above-described configuration will be described in detail with reference to the flowchart of FIG. 2.

Prior to the description, this process assumes that at least two or more CAS interface regions, namely namespace regions, are shared in the digital broadcast receiver in advance, and these CAS interface regions refer to basic variables and functions of CAS software as described above. In this case, the digital broadcast receiver may be set in advance by mutual agreement between the companies.

First, it is assumed that an arbitrary CAS broadcast program, for example, an A CAS broadcast program, is output to the outside through a digital broadcast receiver (S200).

Thereafter, the controller 110 determines whether a change to another CAS broadcast program, for example, a B CAS broadcast program, is requested by the user (S202).

As a result of the determination in step S202, when a change to the B CAS broadcast program is requested, the controller 110 allocates a flash memory area of a specific address to initialize the CAS software download environment (S204). The CAS software download environment initialization process may include checking user information. That is, the change of the CAS broadcasting program operated for a fee is in line with the fact that new charging information is generated. Therefore, the process of updating the charging information in the user information may basically be accompanied. However, since the CAS broadcast program change decision is different from the successful download of the CAS broadcast program or the viewing of the broadcast program, it may be desirable to update only the billing information of the user and determine whether the final payment is made later.

When the initialization process such as updating the charging information is successfully completed, the controller 110 opens the over the air (OTA). That is, an arbitrary download channel for CAS software download is opened (S206). In this case, prior to the download channel opening process, a process of pre-argument whether the currently loaded A CAS software is compatible with the B CAS software to be downloaded may be preceded, and this fact may be obtained by a person skilled in the art. If you grow up, you will easily know.

Thereafter, the controller 110 downloads the B CAS software through the opened download channel (S208).

The controller 110 integrates the namespace with the A CAS software and then replaces the A CAS software mounted in the memory 112 with B CAS software (S210) (S212).

Thereafter, the controller 110 drives the replaced B CAS software to descramble the B CAS broadcast program (S214) (S216).

Through this descrambling process, the B CAS broadcast program may be finally output (S218).

As described above, when several CAS interface areas are set in advance in the digital broadcasting receiver, and the user later wants to watch the second CAS broadcast program, the second CAS software is arbitrarily downloaded to use the second CAS broadcast program. This is how it is implemented to watch.

As described above, the embodiments of the present invention have been described in detail, but the present invention is not limited to these embodiments, and various modifications may be made by those skilled in the art within the spirit and scope of the present invention described in the claims below.

1 is a block diagram illustrating a conditional access system broadcast program output apparatus in a digital broadcast receiver according to an aspect of the present invention;

2 is a flowchart illustrating a conditional access system broadcast program output method in a digital broadcast receiver according to another aspect of the present invention.

<Description of the symbols for the main parts of the drawings>

100: tuner 102: demodulator

104: CAS 106: Demux

108: MPEG decoder 110: control unit

112: memory section

Claims (6)

A conditional access system broadcast program output device of a digital broadcast receiver, An MPEG decoder which decodes the descrambled transport stream through the conditional access system and outputs the audio / video signal; A memory in which specific conditional access system software of the digital broadcast receiver is mounted; A control unit for managing interfaces and software settings of at least two conditional access systems to selectively replace conditional access system software mounted in the memory Conditional access system broadcast program output device in a digital broadcast receiver comprising a. The method of claim 1, And an interface of the at least two conditional access systems is managed through a namespace area. The method of claim 2, And the namespace area includes variables and functions of the conditional access system. When the first conditional access system broadcast program of the first conditional access system software is output through the digital broadcast receiver, determining whether a change to the second conditional access system broadcast program is requested; Checking user information when a change to the second conditional access system broadcast program is requested; Opening a particular download channel to download the second conditional access system software; Replacing the first conditional access system software with the second conditional access system software via an interface region; Outputting a second conditional access system broadcast program by descrambling a second conditional access system broadcast program by driving the replaced second conditional access system software; Conditional access system broadcast program output method in a digital broadcast receiver comprising a. The method of claim 4, wherein And the interface area is managed through a namespace area. The method of claim 5, wherein And said namespace area is a basic variable and functions of conditional access system software.

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