KR20080057015A - Method, apparatus and medium for playing of digital contents file in mobile terminal - Google Patents

Abstract

A method, a device, and a recording medium for playing a digital contents file in a mobile terminal are provided to increase a response speed to a DRM(Digital Rights Management) contents file execution command by sequentially decoding and playing a predetermined size of encoded data of the DRM contents file stored in the portable terminal. A memory(208) stores a DRM contents file and a license of the DRM contents file. A controller(201) decodes a predetermined size of the DRM contents file by using the license when a command for playing the stored DRM contents file is received. A display unit(211) plays the decoded DRM contents file. The controller determines whether the DRM contents file is encoded or not, and checks whether the license corresponding to the encoded DRM contents file is found when the DRM contents file is encoded. The license includes a decoding key used for decoding the encoded DRM contents file and use limit information for the encoded DRM contents file. A data processor(207) includes a transmitter for encoding and modulating a signal transmitted form an RF processor(206) and a receiver for decoding and demodulating the signal transmitted form the RF processor.

Description

METHOD, APPARATUS AND MEDIUM FOR PLAYING OF DIGITAL CONTENTS FILE IN MOBILE TERMINAL}

1 is a schematic diagram of a general DRM system;

2 is a block diagram of a mobile terminal according to an embodiment of the present invention;

3A and 3B are flowcharts illustrating a method of playing a DRM content file stored in a mobile terminal according to one embodiment of the present invention;

4 is a data flow diagram between a DRM execution unit and a DRM authentication unit of a mobile terminal according to one embodiment of the present invention;

5A and 5B are diagrams illustrating a license purchase recommendation menu output of DRM content stored in a mobile terminal according to one embodiment of the present invention;

6 is a block diagram of DRM content data stored in a mobile terminal according to an embodiment of the present invention.

The present invention relates to a digital content file playback method, apparatus, and a recording medium of a mobile terminal. In particular, the DRM content file is sequentially decrypted by playing a predetermined amount of encrypted data of a multimedia content file to which digital rights management (DRM) technology is applied. A method, apparatus and recording medium for increasing the response speed to an execution command.

Recently, multimedia contents to which digital rights management (DRM) technology is applied are increasing. The basic function of the DRM is not to disable content duplication itself, but to allow the duplication freely, but to use the duplicated content again to charge a fee. That is, by allowing the multimedia content encrypted by the DRM technology to be stored in an information processing device such as a personal computer, a portable terminal, etc. equipped with a mass storage device through a wired or wireless communication network or the Internet, access to the mass multimedia content is Unlimited for everyone, but to decrypt and play encrypted digital content, you need a license called the Rights Object. Therefore, applying the DRM technology to any digital content file can effectively protect the digital content.

1 is a schematic diagram of a general DRM system. The mobile terminal 101 transmits a message 105 requesting the content desired by the user to the content server 102. The content server 102 transmits the content 106 to which the DRM 1 is applied to the mobile terminal 101. The application of DRM 1 means that the content has been encrypted using the encryption key and encryption format specified in DRM 1, and the usage rule (Usage Rule, the number of times that can be played back, and the playable content) according to the format specified in DRM 1 is used. Period, etc.) is recorded. Subsequently, the mobile terminal 101 transmits a message 107 requesting a license for the received content 106 to the license server 103. The license is a certificate of granting a right to use a predetermined content, and includes a decryption key and usage restriction information used to decrypt the received content. Therefore, for example, if the content is DRM 1 is applied, the mobile terminal 101 can play the content to which the DRM 1 is applied only if a license prescribed by the DRM 1 system is granted. The license server 103 checks whether the user is a legitimate user. If the legitimate user, the license server 103 generates a license 108 for the content 106 to which the DRM 1 is applied and transmits it to the mobile terminal 101. The license 108 includes a decryption key and restriction information for use in DRM 1. Depending on the implementation, the license server 103 may be implemented as a DRM server 108 in conjunction with the content server 102. The mobile terminal 101 plays the received content 106 using the license 108. That is, the DRM client program installed in the mobile terminal 101 extracts the decryption key and the usage restriction information used to decrypt the content from the license 108, and examines the number of times of playback and the reproduction period included in the extracted usage restriction information. After checking whether the use of the content does not violate the usage restriction information, if the content is not violated, the content is decrypted using the decryption key and then played.

However, in the related art, when the encrypted content is a large multimedia file, the entire encrypted multimedia file is decrypted and reproduced using the license, which causes a delay in response time to a playback command for the multimedia file.

In other words, when playing large-capacity multimedia data to which DRM technology is applied, the large-capacity multimedia content file is played only after all of the large-capacity multimedia data is decoded by using the license. The problem is that you have to wait.

Accordingly, an object of the present invention is to provide a method, an apparatus, and a recording medium for increasing the response speed to the DRM content file execution command by sequentially decrypting and playing a predetermined amount of the encrypted data of the DRM content file stored in the mobile terminal. .

Another object of the present invention is to provide a method, an apparatus, and a recording medium for increasing the response speed to the DRM content file execution command by separately executing an authentication process and a decryption process for the DRM content file.

In the present invention for achieving the above objects, the method for reproducing a digital content file of a mobile terminal includes a storage process of storing the digital content file and a license for the digital content file, and a playback command for the stored digital content file. A decoding process of decoding a predetermined amount of digital data of the digital content file by using the license upon input, and a reproduction process of decoding the remaining digital data of the digital content file at the same time as playing the decoded predetermined amount of digital data; do.

In addition, in the present invention for achieving the above objects, the mobile device digital content file playback apparatus, the memory for storing the digital content file and the license for the digital content file, and the reproduction of the stored digital content file And a control unit for decoding a predetermined amount of digital data of the digital content file using the license when the command is input, and a display unit for reproducing the decoded digital data.

In addition, in the present invention for achieving the above object, a recording medium in which a computer program storing a digital content file reproducing method of a mobile terminal is recorded, a storing process of storing the digital content file and a license for the digital content file. And a decoding process of decoding a predetermined amount of digital data of the digital content file by using the license when inputting a reproduction command for the digital content file, and simultaneously playing the decoded predetermined amount of digital data. And a computer readable recording medium having recorded thereon a computer program for executing a reproduction process for decoding the remaining amount of digital data.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The portable terminal according to an exemplary embodiment of the present invention may include a photographing function, a mobile communication function, a digital broadcasting reception function, an information processing function, or the like.

2 is a block diagram of a mobile terminal according to an embodiment of the present invention. Referring to FIG. 2, the portable terminal includes a controller 201, an audio processor 204, a key input unit 205, an RF processor 206, a data processor 207, a memory 208, and a camera. A camera module 209, an image processor 210, and a display unit 211 are included. The control unit 201 includes a DRM execution unit 202 and a DRM authentication unit 203.

The controller 201 performs a function of controlling the overall operation of the portable terminal and the signal flow between internal blocks of the portable terminal. In addition, the controller 201 may include a function of the data processor 207. In addition, the control unit 201 is an audio processor 204, a key input unit 205, a data processor 207, a memory 208, a camera unit 209, and an image processor 210 according to an exemplary embodiment. And control the signal flow between the display unit 211. In particular, the control unit 201 includes a DRM execution unit 202 and a DRM authentication unit 203.

The DRM execution unit 202 checks the format of any content stored in the memory 208 when inputting a content playback command to determine whether the content is DRM content, and is responsible for a series of processes related to decoding and playing the DRM content file. do.

When the DRM authentication unit 203 inputs a playback command for the DRM content stored in the memory 208, the DRM authentication unit 203 checks whether there is a playback right for the DRM content. When the license for the DRM content file is provided, the DRM content file can be played.

The audio processor 204 converts the voice / sound data into an audible sound through a speaker SPK under the control of the controller 201 and outputs the audio signal such as a voice received from the microphone MIC. Output

The key input unit 205 includes a plurality of numeric, character and / or function keys for inputting numeric and character information and for setting various functions. The key input unit 205 is a device that receives information related to user setting and control, and outputs a keyword input signal to the controller 201.

The RF processor 206 is responsible for a series of communication related to the transmission and reception of content (contents) via a mobile communication network or a wired or wireless Internet network. The RF processor 206 may include an RF transmitter for upconverting and amplifying a frequency of a transmitted signal, and an RF receiver for low noise amplifying and downconverting a received signal.

The data processor 207 may include a transmitter configured to encode and modulate a signal transmitted through the RF processor 206, a receiver configured to demodulate and decode a signal received through the RF processor 206. The data processor 207 may include a modem and a codec. The codec includes a data codec for processing packet data and an audio codec for processing an audio signal such as voice.

The memory 208 may largely include a program memory area and a data memory area. The program memory area stores an operating system for booting the portable terminal, a program for configuring a standby screen of the portable terminal, other options of the portable terminal such as a camera function, a sound playback function, an image or video playback function, and the like. do.

The data memory area is an area in which data generated according to the use of a mobile terminal is stored and stores DRM content that is moved or copied through an external memory or a hard disk, and DRM content that is downloaded through a web server of a wired / wireless internet network. Can be.

The camera unit 209 captures a subject under the control of the controller 201 to receive an optical signal, converts the input optical signal into a digital signal, and outputs the digital signal. To this end, the camera unit 209 converts the photographed optical signal into an electrical signal, that is, an analog signal, a camera sensor, and a digital signal transmitted from the camera sensor. It may include a signal processing unit for converting to. The camera sensor may include a complementary metal oxide semiconductor (CMOS) or a charge coupled device (CCD) sensor, and the signal processor may include a digital signal processor (DSP). The camera unit 209 may be omitted depending on the form of provision of the mobile terminal.

The image processor 210 converts a digital signal output from the camera unit 209 into an image signal to generate screen data. For example, the image processor 210 processes the digital signal output from the camera unit 209 into an image signal in a frame unit, and processes the image signal in the frame unit in the display unit 211. And output in accordance with the standard. The image processor 210 includes an image codec, and compresses an image signal output to the display unit 211 in a selected manner or restores the compressed frame image signal to an original frame image signal. Perform. Here, the image codec may include a JPEG codec, an MPEG4 codec, a wavelet codec, and the like.

The display unit 211 displays screen data output from the image processor 210. The display unit 211 may include a liquid crystal display (hereinafter, referred to as an LCD). When the LCD is formed in a touch screen form, the display unit 211 may be Data input function can be performed.

3 is a flowchart illustrating a playback procedure of a DRM content file stored in a mobile terminal according to an embodiment of the present invention, and FIG. 4 is a diagram illustrating data between a DRM execution unit and a DRM authentication unit of a mobile terminal controller according to an embodiment of the present invention. Processing flow chart.

Referring to FIG. 3, in step S 301, the portable terminal is in a standby state in which power is turned on.

In step S303, the control unit 201 receives a digital content file from an arbitrary content server through a wired or wireless communication network or a wired or wireless internet network, and stores the digital content file in the memory 208. The digital content file includes a large multimedia file to which DRM is applied.

In step S 305, the DRM execution unit 202 of the control unit 201 checks whether an execution command for the stored digital content file is input. The execution command may be input through the key input unit 205 or the display unit 211 having a touch screen function.

In step S 307, the DRM execution unit 202 determines whether the digital content file is encrypted. In the present invention, when a predetermined decryption key is required to execute an arbitrary digital content file, it is determined that the digital content file is encrypted. If the digital content file is not encrypted, the control unit 201 plays the digital multimedia content file according to the execution command in step S309.

However, if it is determined that the digital content file is encrypted, in step S 311, the DRM authentication unit 203 determines whether a license for the digital content file exists. The license is stored in the memory 208 when the DRM content file is stored or through a separate purchase procedure (see FIG. 1 above).

If it is determined that the license does not exist, the controller 201 outputs a license purchase recommendation menu for the DRM content file to which the execution command is input to the display unit 211 in step S 313. 5A and 5B illustrate an embodiment of the outputted license recommendation menu. When the 'Yes' menu is selected in the screen shown in FIG. 5A, the screen shown in FIG. 5B is output, and when a specific menu is selected in FIG. 5B, the controller 201 accesses the wired / wireless communication network or the wired / wireless internet network. You can purchase a license.

In step S 315, the DRM authentication unit 203 determines whether a license for the DRM content file exists. If it is determined that the license for the DRM content file has not been purchased despite the recommendation to purchase, the playback procedure for the DRM content file to which the execution command is input is not performed and the content file execution procedure is terminated.

However, if it is determined in step S 311 or step S 315 that the license for the DRM content file in which the execution command is input is provided, the DRM authentication unit 203 uses the license for the digital content file in step S 317. To open the digital content file (i.e. access to an encrypted content file; the right to use the digital content file is consumed according to the use of the license; for example, 1 out of 3 usage rights). Use times).

In step S319, the DRM execution unit 202 reads a predetermined amount of digital data of the encrypted digital content file. The data amount to be read varies depending on the data processing capacity of the mobile terminal. For example, if the data processing capacity of a mobile terminal is 500 Megabytes per second, a digital content file having a total data amount of 2 Gigabytes is read out by 500 MBytes.

In step S 321, the DRM execution unit 202 decodes a predetermined amount of digital data of the read digital content file. The decryption method is a method of encrypting the read DRM file, and decrypts the read DRM file using a decryption key included in the license.

In step S 323, the DRM execution unit 202 buffers the decoded predetermined amount of digital data, and in step S 325, the DRM execution unit 202 outputs the buffered predetermined amount of digital data to the display unit 211. do.

See FIG. 4 and FIG. 6 to examine in more detail the processing of digital content data performed in the present invention. 4 is a data flow diagram between a DRM execution unit and a DRM authentication unit of a mobile terminal according to an embodiment of the present invention, and FIG. 6 is a block diagram of multimedia digital content data executed in an embodiment of the present invention.

As shown in FIG. 4, when the DRM execution unit 202 recognizes an execution command input for an arbitrary DRM file stored in the mobile terminal (S401), the DRM execution unit 202 executes an execution command for the DRM file. The input signal is transmitted to the DRM authentication unit 203. The DRM authentication unit 203 checks whether a license exists for the DRM file and, if a license exists, performs an authentication process for the DRM file (S 403). Subsequently, the DRM authentication unit 203 uses the execution right for the DRM file according to the usage restriction information included in the license (S405). That is, the number of times of use of the DRM file is subtracted or the period of use is shortened. The DRM authentication unit 203 notifies the DRM execution unit 202 that the DRM file has been authenticated. The DRM execution unit 202 reads a predetermined amount of digital data of the DRM file which has completed the authentication procedure (S407), decrypts (S409), and buffers the decoded predetermined amount of digital data temporarily in the control unit 201. After performing (S411), the predetermined amount of digital data is output to the display unit 211. As described above, in one embodiment of the present invention, data to be processed in the DRM execution unit 202 and the DRM authentication unit 203 of the mobile terminal control unit 201 by separating the authentication process and the decryption process for any DRM file. By reducing the throughput, the response speed to an arbitrary DRM file execution command is increased.

As shown in FIG. 6, in one embodiment of the present invention, the predetermined amount of digital data (Data 1 (601), Data 2 (602), and Data 3 (603)) are all decoded and then combined again and digitally. It is not output after constructing the content file 604. When the predetermined amount of digital data is decoded, it is immediately output after being buffered temporarily. That is, in one embodiment of the present invention, the digital content file 604 having an arbitrary amount of data is read, decoded, buffered, and output in a predetermined amount (S 325).

In one embodiment of the present invention, the DRM execution unit 202 decodes the data 1 (601) and temporarily stores it in the control unit 201, while decoding the data 2 (602) and temporarily stored in the control unit 201 The decoded digital data Data 1 601 is output to the display unit 211. In addition, while outputting the predetermined amount of digital data (Data 1 601) and checking whether there is undecrypted digital data among the digital data of the digital content file, the undecoded digital data (that is, the digital content file 604). A predetermined amount of digital data (Data 3 (603)) is decoded from the remaining portions except for Data 1 (601) and Data 2 (602). The predetermined amount of the digital data is a data processing capacity of the mobile terminal per predetermined time.

As described above, compared to the conventional method of decoding a predetermined amount of digital data of the content file and then combining the decrypted predetermined amount of digital data to form a completed digital content file and then outputting the encrypted digital content file. In one embodiment of the present invention, since a predetermined amount of digital data is output after the temporary buffering is performed by decoding a predetermined amount of digital data, the response speed to an arbitrary encrypted digital content file execution command increases. do.

According to the present invention, it is possible to increase the response speed to the DRM content file execution command by sequentially decrypting and reproducing a predetermined amount of encrypted data of the DRM content file stored in the mobile terminal.

In addition, according to the present invention, it is possible to increase the response speed to the DRM content file execution command by separating and executing the authentication process and the decryption process for the DRM content file.

Claims (18)

In the digital content file playback method of a mobile terminal, A storage process of storing the digital content file and a license for the digital content file; A decryption process of decrypting a predetermined amount of digital data of the digital content file using the license when inputting a playback command for the stored digital content file; And reproducing the decoded predetermined amount of digital data and decoding the remaining digital data of the digital content file at the same time. The method of claim 1, wherein the storing process, Determining whether the digital content file is encrypted; And determining whether a license for the encrypted digital content file exists when the digital content file is encrypted as a result of the determination. The method of claim 1, wherein the decoding process, Reading a predetermined amount of digital data of the digital content file using the license; And decrypting the read predetermined amount of digital data using the license. The method of claim 1, wherein the reproducing process Buffering the decoded predetermined amount of digital data; Outputting the buffered predetermined amount of digital data; Outputting the predetermined amount of digital data and checking whether there is undecoded digital data among the digital data of the digital content file, and if there is undecoded digital data, decoding a predetermined amount of undecoded digital data. Digital content file playback method of a mobile terminal, characterized in that. The method of claim 2, And the license includes a decryption key used to decrypt the encrypted digital content file and usage restriction information for the encrypted digital content file. The method of claim 3, wherein And a predetermined amount of the digital data to be read and decoded is variable according to the data processing capacity of the mobile terminal. In the digital content file playback apparatus of a mobile terminal, A memory for storing the digital content file and a license for the digital content file; A control unit which decodes a predetermined amount of digital data of the digital content file by using the license when inputting a reproduction command for the stored digital content file; And a display unit for reproducing the decoded digital data. The method of claim 7, wherein the control unit, Determine whether the digital content file is encrypted, And determining whether a license for the encrypted digital content file exists if the digital content file is encrypted. The method of claim 7, wherein the control unit, Read a certain amount of digital data of the digital content file using the license, And decrypting the read predetermined amount of digital data using the license. The method of claim 7, wherein the control unit, Buffering the decoded predetermined amount of digital data, Outputting the buffered predetermined amount of digital data to the display unit, And outputting the predetermined amount of digital data and checking whether there is undecoded digital data among the digital data of the digital content file, and if there is undecoded digital data, decoding a predetermined amount of undecoded digital data. Digital content file playback device of a mobile terminal. The method of claim 8, And the license includes a decryption key used to decrypt the encrypted digital content file and usage restriction information for the encrypted digital content file. The method of claim 9, And a predetermined amount of the digital data to be read and decoded is variable according to the data processing capacity of the mobile terminal. In a recording medium on which a computer program storing a digital content file reproduction method of a mobile terminal is recorded, A storage process of storing the digital content file and a license for the digital content file; A decryption process of decrypting a predetermined amount of digital data of the digital content file by using the license when inputting a reproduction command for the digital content file; And a reproducing process of reproducing the decoded predetermined amount of digital data and decoding the remaining predetermined amount of digital data of the digital content file. The method of claim 13, wherein the storing process, Determining whether the digital content file is encrypted; And if the digital content file is encrypted as a result of the determination, determining whether a license for the encrypted digital content file exists. The method of claim 13, wherein the decoding process, Reading a predetermined amount of digital data of the digital content file using the license; And decoding the read predetermined amount of digital data by using the license. The method of claim 13, wherein the reproducing process, Buffering the decoded predetermined amount of digital data; Outputting the buffered predetermined amount of digital data; Outputting the predetermined amount of digital data and checking whether there is undecrypted digital data among the digital data of the digital content file, and if there is undecoded digital data, decoding a predetermined amount of undecoded digital data. The recording medium having a computer program recorded thereon. The method of claim 14, And the license includes a decryption key used to decrypt the encrypted digital content file and usage restriction information for the encrypted digital content file. The method of claim 15, And said predetermined amount of digital data to be read and decoded is variable according to the data processing capacity of the portable terminal.

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