KR102461348B1 - Method and apparatus for playing media contens based on digita rights management - Google Patents

Abstract

In the playback device according to the present disclosure, a method of playing content included in a media file includes: obtaining file status indication information indicating a status of the media file from the media file; When it is indicated that the content included in the file is self-encoded content, the process of checking whether a content authentication code (CAC) for playing the content is included in the media file, and if the CAC is not included, the and a process of playing content, wherein the self-encoded content is content that can be reproduced without the CAC.

Description

Method and apparatus for playing media content based on digital rights management

The present disclosure relates to an apparatus and method for providing a digital rights management (DRM) service.

Digital Rights Management (DRM) is a technology and service that protects and manages the rights and interests of intellectual property rights and copyrights of digital content owners. Only users who have permission to access and use the content can use the content. It is a technique that makes

DRM technologies can be largely divided into software-based DRM methods and media-based DRM methods. The media-based DRM method restricts the consumption of digital content within a specific medium such as a locked-in flash memory, thereby restricting the consumption of digital content only within that medium. On the other hand, the software-based DRM method does not use any method that couples the consumption of digital content to specific hardware.

In order to improve security for content protection while providing more flexibility than device-based DRM, a software-based DRM method has been developed so that the corresponding content can be linked to a specific medium.

In this regard, the Blu-ray Disc Association (BDA), which is a standardization organization related to Blu-ray Disc, is discussing a Blu-ray Disc bridge (BD bridge) system. The BD bridge system is for copying content included in the Blu-ray Disc to another medium, for example, a hard disk in a computer, or a memory card of a mobile device so that a user can consume the content. The BD bridge system stipulates SFF (Standard File Format) compatible with CFF (Common File Format), which is used as a standard format for digital copying and video transmission, and is included in Blu-ray discs purchased by users in devices that support SFF. It makes the content available for consumption. However, since there is a problem of digital copyright in such a Blu-ray bridge system, it is necessary to allow a legitimately authorized user to consume the content included in the Blu-ray Disc.

An embodiment of the present disclosure includes information indicative of the status of a media file in a media file, and a method for a playback device to perform a licensing operation or a playback operation related to the media file based on the information indicating the status of the file and devices.

An embodiment of the present disclosure provides a method and an apparatus for performing a licensing operation or a playback operation related to a media file according to whether the content included in the media file is self-encoded content or prepared content.

An embodiment of the present disclosure provides a method and an apparatus for performing a licensing operation or a reproduction operation related to a media file according to whether the content included in the media file was previously licensed through DRM.

A method of reproducing content included in a media file in a playback device, provided by an embodiment of the present disclosure, includes: acquiring file status indication information indicating a status of the media file from the media file; and the file status indication information indicates that the content included in the media file is self-encoded content, the process of checking whether the media file includes a content authentication code (CAC) for playing the content, and the CAC is not included otherwise, the content is reproduced, and the self-encoded content is content that can be reproduced without the CAC.

A playback apparatus for reproducing content included in a media file provided by an embodiment of the present disclosure includes a media file analyzer configured to obtain file status indication information indicating a status of the media file from the media file, and the file status indication information When indicates that the content included in the media file is self-encoded content, it is checked whether the media file includes a Content Authentication Code (CAC) for playing the content, and the CAC is included If not, it includes a control unit for playing the content, the self-encoded content is characterized in that the content that can be reproduced without the CAC.

1 is a diagram for explaining a method of reproducing an SFF file according to a media-based DRM method by DBEF (Digital Bridge Export Function) of BDA;
2 is a view for explaining the structure of an SFF common file format including CAC flag information according to an embodiment of the present disclosure;
3 is a diagram illustrating a DRM system according to an embodiment of the present disclosure;
4 is a diagram illustrating a method for content licensing and reproduction on a DRM medium according to an embodiment of the present disclosure;
5 is a view for explaining the operation of the DRM device for the prepared content in which the CAC flag does not exist according to an embodiment of the present disclosure;
6 is a view for explaining an operation of a DRM device for prepared content in which a CAC flag exists according to an embodiment of the present disclosure;
7 is a view for explaining an operation of a DRM device for self-encoded content in which a CAC flag is present according to an embodiment of the present disclosure;

In the following description of the present disclosure, if it is determined that a detailed description of a related well-known function or configuration may unnecessarily obscure the subject matter of the present disclosure, the detailed description thereof will be omitted. Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

Although the embodiments of the present disclosure described below are separated for convenience of description, at least two or more embodiments may be combined and performed within a range that does not conflict with each other.

Terms to be described below are terms defined in consideration of functions in embodiments of the present disclosure, which may vary according to intentions or customs of users and operators. Therefore, the definition should be made based on the content throughout this specification.

The embodiment of the present disclosure may have various changes and may have various embodiments, and specific embodiments will be described in detail by exemplifying the drawings. However, this is not intended to limit the present disclosure to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present disclosure.

Also, terms including an ordinal number such as first, second, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present disclosure, a first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

In addition, the terms used herein are used only to describe specific embodiments, and are not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present specification, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that this does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

In addition, in the embodiments of the present disclosure, unless otherwise defined, all terms used herein, including technical or scientific terms, are generally understood by those of ordinary skill in the art to which the present disclosure belongs. have the same meaning as Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in an embodiment of the present disclosure, an ideal or excessively formal meaning is not interpreted as

Hereinafter, various embodiments will be described in detail with reference to the accompanying drawings. In this case, it should be noted that in the accompanying drawings, the same components are denoted by the same reference numerals as much as possible. In addition, detailed descriptions of well-known functions and configurations that may obscure the gist of the present disclosure will be omitted. It should be noted that in the following description, only parts necessary for understanding operations according to various embodiments of the present disclosure will be described, and descriptions of other parts will be omitted so as not to obscure the gist of the present disclosure.

The apparatus and method proposed in the present disclosure include a Long-Term Evolution (LTE) mobile communication system, a Long-Term Evolution-Advanced (LTE-A) mobile communication system, and a high-speed downlink A high speed downlink packet access (HSDPA) mobile communication system, a high speed uplink packet access (HSUPA) mobile communication system, and a 3rd generation project partnership 2 (3rd generation project partnership 2: 3GPP2) High rate packet data (HRPD) mobile communication system, 3GPP2 Wideband Code Division Multiple Access (WCDMA) mobile communication system, and 3GPP2 Code Division Multiple Access (Code Division Multiple Access: CDMA) mobile communication system, Institute of Electrical and Electronics Engineers (IEEE) 802.16m communication system, Evolved Packet System (EPS), and Mobile Internet Protocol (Mobile Internet Protocol: Mobile) It is applicable to various communication systems, such as an IP) system.

The following description of the present disclosure will be described based on the SFF file of the BD bridge system. However, this is only for convenience of description, and the present disclosure is not limited only to the BD bridge system.

In general, software-based DRMs are common file formats such as Common File Format (CFF) of Dolby Digital Entertainment Content Ecosystem (DECE) or Standard File Format (SFF) of Blu-ray Disc Association (BDA). However, the media-based DRM method requires additional DRM-specific information in order to reproduce the content included in the common format file.

FIG. 1 is a diagram for explaining a method of reproducing an SFF file according to a media-based DRM method by a DBEF (Digital Bridge Export Function) of BDA.

Referring to FIG. 1 , when a Blu-ray Disc (BD) 101 including an SFF file is inserted into the BD player 103 , the BD player 103 transmits the SFF file to the user including the DRM medium 107 . Move to a DRM device (not shown). The DRM medium 107 may be in the form of, for example, a flash memory such as an SD card.

On the other hand, the SFF file 105 moved to the DRM medium 107 additionally receives DRM-specific information through the DRM server 109 and the DRM licensing procedure (108), and uses the received DRM-specific information. Contents included in SFF files can be played. For reference, the "licensing procedure" refers to a procedure for obtaining a legitimate right for a DRM device to reproduce an SFF file.

However, existing common file formats such as SFF do not provide sufficient information for a DRM device to implement a media-based DRM scheme. Although the SFF includes DRM-specific information required for content reproduction, the DRM-specific information in the SFF is typically included in a Protection System Specific Header (PSSH) box in the SFF. However, the PSSH box is not sufficient to provide information for licensing used by media-based DRMs. This may be because the size or function of the PSSH box is limited. In addition, it may be due to reasons other than the size or function limitation.

Meanwhile, during the licensing procedure for the medium-based DRM method, content authentication code (CAC) information may be included in the content authentication code (CAC) box included in the SFF file. The CAC information includes a set of hash values calculated from a content file included in a media data (mdat) box. This licensing scheme is one of the schemes used in media-based DRM schemes in order to bind the corresponding content to the media.

The basic concept of the present disclosure is to insert "file status indication information" indicating the status of the corresponding media content file into a file including the media content. The DRM device may obtain the file status indication information and perform an operation such as content reproduction or a licensing procedure with a DRM server based on the obtained file status indication information.

In the present disclosure, the file including the media content may be a common format file such as SFF. Hereinafter, for convenience of description, an SFF file by DBEF of BDA will be described as an example of a common format file. However, this is only for convenience of description, and the present disclosure is not limited to the SFF file by DBEF of BDA.

As an embodiment of the present disclosure, the file status indication information may be included in a PSSH box in the SFF. However, it is not necessarily included in the PSSH box, and may be included in an appropriate location in the SFF file.

The file status indication information may be, for example, information in the form of a flag having a size of 1 bit. For convenience of description, the file status indication information will be referred to as "CAC flag information" having a size of 1 bit. Therefore, in the present disclosure, “file status indication information” may be used interchangeably with “CAC flag information”.

On the other hand, the "status" of the file in the file status indication information means (1) whether the file has been licensed at least once for a specific medium before, and (2) the contents of which the file is prepared. It may mean whether to include or whether to include self-encoded file content.

For reference, the "self-encoded content" is content that does not require CAC information in the SFF file for content reproduction. Therefore, the DRM device does not need to receive the CAC information from the DRM server during the DRM licensing procedure for the reproduction of the self-encoded content. On the other hand, the "prepared content" is content that requires CAC information in the SFF file for content reproduction. Therefore, the DRM device receives the CAC information from the DRM server during the DRM licensing process to reproduce the self-encoded content, and inserts the received CAC information into the SFF file.

2 is a diagram for explaining the structure of the SFF common file format including CAC flag information according to an embodiment of the present disclosure.

Referring to FIG. 2 , the SFF file 200 includes a PSSH box 201 and at least one data box (eg, an mdat box). Meanwhile, the PSSH box 201 includes 1-bit CAC flag information 203 proposed by the present disclosure, and the CAC flag information 203 indicates the state of the SFF common file 200 . In addition, the SFF file 200 may further include a CAC box 207 including CAC information.

3 is a diagram illustrating a DRM system according to an embodiment of the present disclosure.

Referring to FIG. 3 , the DRM system according to the present disclosure includes an SFF file 331 in a DRM server 310 , a DRM device 320 and a DRM medium 330 .

The DRM device 320 includes an SFF analyzer 321 , a controller 323 , a transceiver 325 , and an SFF generator 327 . However, since SFF in FIG. 3 is an example of a media file, SFF in the name of each functional block in FIG. 3 may be replaced with a media file. For example, the SFF analyzer 321 may be referred to as a media file analyzer.

The SFF analyzer 321 analyzes components included in the SFF file. In particular, in an embodiment of the present disclosure, CAC flag information is detected and its value is identified. In addition, the SFF analyzer 321 analyzes the presence or absence of the position of the CAC box and offsetToCAC information capable of indicating the position, and outputs the result. For reference, if the CAC box does not exist, the offsetToCAC does not exist. However, in order to additionally check whether the content in the SFF is properly licensed, the SFF analyzer 321 attempts to read the offsetToCAC even when the CAC flag is 1 or 0.

Accordingly, the SFF analyzer 321 analyzes the SFF file, and identifies whether the CAC flag exists and, if the CAC flag exists, the value of the corresponding CAC flag. On the other hand, to find the location of the CAC box, the offsetToCAC is analyzed, and the CAC box is identified. In addition, the analysis result is transmitted to the control unit 323 .

The control unit 323 receives the information transmitted from the SFF analysis unit 321, that is, the existence of the CAC flag, the value of the corresponding CAC flag, and the information on the existence of the CAC box, and based on these information, the DRM Controls the overall operation of the device 320 . For example, based on the information, it is determined to receive DRM-specific information from the DRM server 310 for content reproduction through the DRM server 310 and a licensing procedure, or the content is played without a licensing procedure, Alternatively, it may be decided to stop the operation without playing the corresponding content. For reference, the DRM-specific information includes CAC information, NSM (Next Generation Secure Memory) unique PSSH files, an XORed title key, and the like. For reference, the XORed title key is generated from a title key, usage rules, CAC signature, and the like, and is encrypted and stored in a storage medium in the form of an XORed title key of the title key.

When the control unit 323 determines to receive DRM-specific information from the DRM server 310 , the transceiver 325 may request and receive DRM-specific information from the DRM server 310 .

The SFF generator 327 may insert 1-bit CAC flag information having a predetermined value in a specific location in the SFF file, for example, in a PSSH box. In addition, CAC information may be inserted into the CAC box using the DRM-specific information received from the DRM server 310 .

On the other hand, the DRM medium 330 is a medium such as a flash memory (eg, an SD card), a medium to which a right to consume the corresponding content is granted, and includes the SFF file 331 .

The DRM server 310 receives a request for unique DRM information from the transceiver 325 of the DRM device 320 , and provides the unique DRM information to the DRM device 320 accordingly. The unique DRM information may be CAC information, DRM-specific PSSH files, or an XORed title key.

Hereinafter, CAC flag information according to an embodiment of the present disclosure will be described.

The CAC flag information has a predetermined size, for example, a size of 1 bit, and may be inserted into the PSSH box of the SFF file stored in the DRM media. In addition, the CAC flag information is inserted into the PSSH box when the SFF has been previously licensed through DRM based on a specific medium at least once. On the other hand, if the SFF file has never been licensed through DRM based on a specific medium, CAC flag information is not inserted.

Meanwhile, when CAC flag information is inserted, the CAC flag value may indicate whether the content of the SFF file is self-encoded content or prepared content. For example, when the value of the CAC flag information is set to "0", it indicates that the corresponding SFF file includes "self-encoded content" and that CAC information is not required for content reproduction. On the other hand, when the value of the CAC flag information is set to "1", the corresponding SFF file includes "prepared content", indicating that CAC information is required for content reproduction. However, it goes without saying that the value “0” or “1” of the CAC flag information may be set opposite to the above example.

The "self-encoded content" is content that does not require CAC information in the SFF file for content reproduction, and a CAC flag value is set to 0 by a home device that is an apparatus for generating an SFF file. Meanwhile, the "prepared content" is content that requires CAC information in an SFF file for content reproduction, and the CAC information may be received from a DRM server during a DRM licensing process and inserted into the SFF file.

4 is a diagram illustrating a method for content licensing and reproduction on a DRM medium according to an embodiment of the present disclosure.

4 may be described by dividing the operation into three parts for convenience.

The first operation 410 is a process of checking the presence or absence of a CAC flag in the SFF file and identifying the value of the corresponding CAC flag, and the second operation 420 is a CAC box when the value of the CAC flag bit is 0. It is a process of checking whether or not exists in the SFF file, and the third operation 430 is an operation of checking whether the CAC box exists in the SFF file when the value of the flag bit is 1. The detailed operation is as follows.

In step 411, it is checked whether the CAC flag exists. As a result of the check, if the CAC flag does not exist in step 412 , the process proceeds to step 414 . For reference, as described above, if the SFF file has never been licensed through DRM based on a specific medium, CAC flag information is not inserted. Therefore, the absence of the CAC flag in step 411 means that the SFF file has never been licensed through DRM based on a specific medium.

Meanwhile, in step 414, since the CAC flag does not exist in the SFF file, the CAC flag is inserted. At this time, the CAC flag value is set to 1, and the reason is as follows. However, if the content of the corresponding SFF file is "self-encoded content", the CAC flag generated during the self-encoding and encryption process for the self-encoded content should be included in the SFF file. However, since the CAC flag does not exist in the current SFF file, it can be assumed that the corresponding content is "prepared content" rather than "self-encoded content". As described above, when the value of the CAC flag information is set to “1”, it indicates that the corresponding SFF file is “prepared content”. Therefore, the value of the CAC flag is set to 1 to indicate that the corresponding content is prepared content. After that, it goes back to step 411 again.

If the CAC flag exists in step 411, the process proceeds to step 413 to identify the value of the corresponding CAC flag. If the value of the CAC flag is 0, the process proceeds to step 421 or less, and if the value of the CAC flag is 1, it proceeds to step 431 or less.

As described above, when the value of the CAC flag is 0, the corresponding SFF file includes "self-encoded content", and additional CAC information is not required for content reproduction. Therefore, there is no need to receive CAC information from the DRM server from the DRM server. On the other hand, if the value of the CAC flag is "1", the corresponding SFF file includes "prepared content", and it is necessary to receive CAC information from the DRM server for content reproduction. According to this difference, an operation below step 421 and an operation below step 431 are distinguished.

First, after step 421, that is, when the value of the CAC flag is set to "0", the corresponding SFF file includes "self-encoded content" and there is no need to receive additional CAC information for content reproduction. The action is as follows.

In step 421, the DRM device reads the value of offsetToCAC, and accordingly, in step 422, determines whether a CAC box exists. If the CAC box exists in step 422, the operation is stopped in step 423.

The reason for stopping the operation in step 422 is that it can be estimated that there is an error in the corresponding SFF file. That is, since the content included in the current SFF file is self-encoded content in which the CAC flag value is set to 0, the CAC box should not exist. However, the fact that the CAC box is detected means that there is an error in the current SFF file, such as an error in the value of the CAC flag set to "0". Therefore, in step 423, it is determined that there is an error in the current SFF file, and the operation is stopped without playing the SFF file.

Meanwhile, if the CAC box does not exist in step 422, the process proceeds to step 424. Since the CAC box is not required for the reproduction of the self-encoded content, the absence of the CAC box in the SFF file means that there is no error in the corresponding SFF file. Accordingly, the DRM device plays the content included in the corresponding SFF file (without receiving an additional CAC file from the DRM server).

After step 431, that is, when the value of the CAC flag is set to "1", the corresponding SFF file includes "prepared content", and additional CAC information needs to be received from the DRM server for content reproduction. Is as follows.

In step 431, the DRM device reads the value of offsetToCAC, and accordingly determines whether a CAC box exists in step 432.

If the CAC box exists in step 432, the process proceeds to step 433 to reproduce the CAC information corresponding to the content. Specifically, the DRM device may decrypt the encryption key using the CAC information included in the SFF file, and reproduce the corresponding content using the decrypted encryption key.

On the other hand, if the CAC box does not exist, it proceeds to step 434 to request a CAC file from the DRM server, and receives the CAC file in step 435 . Thereafter, in step 433, the corresponding content is played using the received CAC file.

5 is a diagram for explaining an operation of a DRM device for prepared content in which a CAC flag does not exist according to an embodiment of the present disclosure. For reference, the absence of the CAC flag indicates that the corresponding content has never been previously licensed for a specific medium. The description of FIG. 5 corresponds to the process of 410 of FIG. 4 .

In step 501 , the DRM device 320 transmits a signal for checking whether the CAC flag exists in the SFF file in the DRM medium 330 to the DRM medium 330 . When receiving a response that the CAC flag does not exist in the SFF file from the DRM medium 330 in step 503, the DRM device 320 generates a CAC flag having a value of “1” in step 503 and inserts it into the SFF file. . The reason for setting the CAC flag to 1 is that the corresponding content is estimated as "prepared content" as described above in step 414 of FIG. 4 .

6 is a diagram for explaining an operation of a DRM device for prepared content having a CAC flag according to an embodiment of the present disclosure. For reference, the presence of the CAC flag indicates that the content has been previously licensed for a specific medium. In addition, since FIG. 6 assumes the prepared content, if there is no error in the SFF file, the value of the CAC flag will be set to 1.

In step 601 , the DRM device 320 transmits a signal for checking whether a flag exists in the SFF file in the DRM medium 330 to the DRM medium 330 . In step 603, a response indicating that the CAC flag exists in the SFF file and that the value of the corresponding CAC flag is 1 is received from the DRM medium 330 .

In step 605, the DRM device 320 reads the offsetToCAC to find the location of the CAC box, and inquires about the existence of the CAC box to the DRM medium 330. In step 607, the DRM medium 330 responds to the existence of the CAC box. In step 609, the DRM device 320 determines to receive CAC information from the DRM server 310 based on the value of the CAC flag and the existence of the CAC box, or the content in the SFF file without receiving the CAC information. decide to play

Specifically, if the CAC box exists, the process proceeds to step 617 to reproduce content using CAC information in the CAC box. On the other hand, if the CAC box does not exist, CAC information is requested from the DRM server 310 in step 611, CAC information is received in step 613, and the CAC information received in step 615 is recorded in the SFF file in the medium. Thereafter, the corresponding content is reproduced using the recorded CAC information in step 617 .

7 is a diagram for explaining an operation of a DRM device for self-encoded content in which a CAC flag exists according to an embodiment of the present disclosure.

For reference, in the case of self-encoded content, when the self-encoded content is encoded by a home device that generates the corresponding content, a CAC flag is also generated. Accordingly, in FIG. 7 , it was assumed that the self-encoded content includes CAC flag information. In addition, since FIG. 7 assumes self-encoded content, it is assumed that the value of the CAC flag is set to "0".

In step 701 , the DRM device 320 transmits a signal for checking whether a flag exists in the SFF file in the DRM medium 330 to the DRM medium 330 . In step 703, a response indicating that the CAC flag exists in the SFF file and that the value of the corresponding CAC flag is 0 is received from the DRM medium 330 .

In step 705, the DRM device 320 reads the value of offsetToCAC, and inquires about the existence of the CAC box to the DRM medium 330. In step 707, the DRM medium 330 responds to the existence of the CAC box. In step 609, the DRM device 320 determines the operation of the DRM device based on the value of the CAC flag and the existence of the CAC box.

Specifically, if the CAC box exists, it is determined that there is an error in the current SFF file, and the operation is stopped without playing the SFF file. On the other hand, if the CAC box does not exist, since the CAC box is not required for the reproduction of the self-encoded content, this means that there is no error in the SFF file, and thus the content included in the corresponding SFF file is reproduced.

Certain aspects of the present disclosure may also be embodied as computer readable code on a computer readable recording medium. A computer readable recording medium is any data storage device capable of storing data that can be read by a computer system. Examples of the computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes and , floppy disks, optical data storage devices, and carrier waves (such as data transmission over the Internet). The computer readable recording medium may also be distributed over network-connected computer systems, so that the computer readable code is stored and executed in a distributed manner. In addition, functional programs, code, and code segments for accomplishing the present disclosure may be readily interpreted by programmers skilled in the art to which the present disclosure is applied.

In addition, it will be appreciated that the apparatus and method according to an embodiment of the present disclosure may be realized in the form of hardware, software, or a combination of hardware and software. Any such software, for example, whether erasable or rewritable, may include a volatile or non-volatile storage device such as a ROM, or a memory such as, for example, RAM, a memory chip, device or integrated circuit. , or an optically or magnetically recordable storage medium, such as a CD, DVD, magnetic disk or magnetic tape, and a machine (eg, computer) readable storage medium. The method according to an embodiment of the present disclosure may be implemented by a computer or portable terminal including a control unit and a memory, wherein the memory is suitable for storing a program or programs including instructions for implementing embodiments of the present disclosure You will see that it is an example of a machine-readable storage medium.

Accordingly, the present disclosure includes a program including code for implementing the apparatus or method described in any claim of the present specification, and a machine (computer, etc.) readable storage medium storing such a program. Also, such a program may be transmitted electronically over any medium, such as a communication signal transmitted over a wired or wireless connection, and the present disclosure suitably includes the equivalents thereto.

Also, the apparatus according to an embodiment of the present disclosure may receive and store the program from a program providing apparatus connected by wire or wirelessly. The program providing device may include a program including instructions for the program processing device to perform a preset content protection method, a memory for storing information necessary for the content protection method, and wired or wireless communication with the graphic processing device. It may include a communication unit for performing, and a control unit for automatically transmitting the program to the transceiver at a request of the graphic processing device or automatically.

On the other hand, although specific embodiments have been described in the detailed description of the present disclosure, various modifications may be made without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments and should be defined by the claims described below as well as the claims and equivalents.

Claims (16)

A method for playing content included in a media file in a playback device, the method comprising:
A process of identifying whether a Content Authentication Code (CAC) flag is included in the media file - the CAC flag indicates that the media file is self-encoded content for which CAC is not required for playback of content set to one of a first value indicating that includes or a second value indicating that the media file includes prepared content indicating that the CAC is required for content reproduction;
identifying a value of the CAC flag when the CAC flag is included in the media file;
When the value of the CAC flag is the first value, CAC offset information indicating the location of the CAC box including the CAC is obtained from the media file, and the CAC box is stored in the media file based on the CAC offset information. identifying whether the CAC box is included in the media file, identifying an error in the media file, and if the CAC box is not included in the media file, play the self-encoded content of the media file process; and
When the value of the CAC flag is the second value, CAC offset information indicating the location of the CAC box including the CAC is obtained from the media file, and the CAC box is stored in the media file based on the CAC offset information. is included, and if the CAC box is included in the media file, the prepared content of the media file is played using the CAC in the CAC box, and if the CAC box is not included in the media file, DRM (Digital Rights Management) comprising the process of obtaining the CAC from a server, Method. The method of claim 1 , further comprising, when the CAC flag is not included in the media file, including the CAC flag set to the second value in the media file. delete delete delete delete delete The method of claim 1, wherein the media file is encoded in a standard file format (SFF). A playback device for playing content included in a media file, the playback device comprising:
Memory; and
a control unit, the control unit comprising:
Identifies whether a Content Authentication Code (CAC) flag is included in the media file, wherein the CAC flag indicates that the media file contains self-encoded content for which CAC is not required for playback of content. set to one of a first value indicating inclusion or a second value indicating that the media file includes prepared content indicating that the CAC is required for content reproduction;
If the CAC flag is included in the media file, identify a value of the CAC flag,
When the value of the CAC flag is the first value, CAC offset information indicating the location of the CAC box including the CAC is obtained from the media file, and the CAC box is stored in the media file based on the CAC offset information. If the CAC box is included in the media file, identify an error in the media file, if the CAC box is not included in the media file, play the self-encoded content of the media file; ,
When the value of the CAC flag is the second value, CAC offset information indicating the location of the CAC box including the CAC is obtained from the media file, and the CAC box is stored in the media file based on the CAC offset information. is included, and if the CAC box is included in the media file, the prepared content of the media file is played using the CAC in the CAC box, and if the CAC box is not included in the media file, DRM (Digital Rights Management) A playback device, configured to obtain the CAC from a server. The playback apparatus of claim 9 , wherein the control unit is further configured to include a CAC flag set to the second value in the media file when the CAC flag is not included in the media file. delete delete delete delete delete The playback apparatus of claim 9, wherein the media file is encoded in a Standard File Format (SFF).

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