WO2006071064A1

WO2006071064A1 - Method of managing license of content generation module and content playback device implementing the method

Info

Publication number: WO2006071064A1
Application number: PCT/KR2005/004593
Authority: WO
Inventors: Sung-Kyoon Yun
Original assignee: Neomtel Co., Ltd.
Priority date: 2004-12-30
Filing date: 2005-12-28
Publication date: 2006-07-06
Also published as: KR20060078073A

Abstract

Disclosed is a method of managing a software license of a content generation module that is incorporated in a server computer and generates a great amount of multimedia content. A content generation module adds license information of the content generation module to content upon generation of the content, and a content playback device which downloads and plays the content compares the time based on a clock of the content playback device with the license information and, in case the content is generated by a content generation module whose expiry date is over, outputs a message indicating that the content is generated by the content generation module whose expiry date is over. Accordingly, the license information included in the content generation module is recorded in the content without the knowledge of the content provider, and is compared with the clock of the content playback device that plays the content to verify whether or not the license is valid. As a result, it is possible to effectively monitor content providers who use content generation modules produced in an invalid manner.

Description

METHOD OF MANAGING LICENSE OF CONTENT GENERATION MODULE AND CONTENT PLAYBACK DEVICE

IMPLEMENTING THE METHOD

Technical Field

[1] The present invention relates to a technique of controlling the playback of multimedia content and, more particularly, to a technique of controlling the playback of multimedia content to manage a license of a content generation module. Background Art

[2] In general, multimedia content is generated by the use of an authoring tool, or by uploading the multimedia content to an automatic generation module and converting or encoding the multimedia content. A mobile communication terminal is equipped with a playback engine for playing the multimedia content. The playback engine plays specific multimedia content. Examples of the playback engine include a mobile flash playback engine provided by Macromedia Inc., and a SIS playback engine and a VIS playback engine provided by the present applicant. For example, in order to play an image taken by a camera phone in the playback engine of the mobile communication terminal, the image needs to be transmitted to a computer equipped with a content generation module, be converted or encoded, and be downloaded to the mobile communication terminal. Such a conversion process is needed to play Web content in the mobile communication terminal.

[3] The content generation module required for the above-mentioned operation is called an automatic generation library since it is incorporated in a server computer. The content generation module is expensive compared to a general authoring tool since it produces a great amount of content. Conventionally, in order to verify a software license of the content generation module, license information is compared with current system clock when the content generation module is executed. In case the license is expired, a warning message is notified to a user using the content generation module, or the content generation module stops operating. However, there is a problem in that users can fake the system clock to continuously use software whose expiry date is over.

Disclosure of Invention Technical Solution

[4] The present invention provides a license management method of a content generation module that prevents users from using the content generation module in an illegal manner.

[5] The present invention further provides a license management method of a content generation module that verifies whether or not a license of the content generation module is valid. Advantageous Effects

[6] According to the present invention, it is possible to effectively prevent content providers from changing license information concerning content generation modules or from faking a system clock to illegally use the content generation modules for producing a great amount of contents.

[7] Since the license information is verified by the content playback device, it is possible to prevent the content provider from faking the system clock and to induce customers to renew the license agreement.

[8] In addition, it is possible to easily detect the illegal use of the content generation modules since the illegal use is notified by the content playback device. Further, in case the license agreement of the content generation module is renewed, users will not receive a warning message any more when the users play the content produced by the content generation module. Brief Description of the Drawings

[9] The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:

[10] FIG. 1 is a network structure of a license management system according to an embodiment of the present invention;

[11] FIG. 2 is a block diagram of a content playback device according to an embodiment of the present invention;

[12] FIG. 3 is a block diagram of a license management server according to an embodiment of the present invention; and

[13] FIG. 4 is a flow chart of a license management method of a content generation module according to an embodiment of the present invention. Best Mode for Carrying Out the Invention

[14] According to an aspect of the present invention, a content generation module adds license information of the content generation module to content upon generation of the content, and a content playback device which downloads and plays the content compares the time based on a clock of the content playback device with the license information and, in case the content is generated by a content generation module whose expiry date is over, outputs a message indicating that the content is generated by the content generation module whose expiry date is over. [15] Accordingly, the license information included in the content generation module is not compared with a system clock of a content providing server, which may be faked by a content provider. Instead, the license information included in the content generation module is recorded in the content without the knowledge of the content provider, and is compared with the clock of the content playback device that plays the content to verify whether or not the license is valid. As a result, it is possible to effectively monitor content providers who use content generation modules produced in an invalid manner. Further, it is possible to warn users who use the content playback device not to use illegal software.

[16] According to another aspect of the present invention, a content playback device verifies whether or not content is generated by a content generation module produced in a valid manner, and, in case the content is generated in an illegal manner, accesses a license management server and notifies that the content is generated in an illegal manner.

[17] Accordingly, a software licensee can get hold of illegal users in an efficient manner.

[18] According to another aspect of the present invention, in case a license is renewed after a content generation module downloads content, a license management server transmits update information to a content playback device which has been verified to use content generated in an illegal manner, and updates the license information stored in the content.

[19] Accordingly, in case the license is renewed, users will not receive a warning message any more. Mode for the Invention

[20] Exemplary embodiments in accordance with the present invention will now be described in detail with reference to the accompanying drawings.

[21] FIG. 1 is a network structure of a license management system according to an embodiment of the present invention. The license management system includes a license management server 90, a wireless Internet server 30, a wired Internet server 70, a content providing server 50, and a content playback device 10. The wireless Internet server 30 is equipped with a content generation module. The wired Internet server 70 is connected to a personal computer (PC) 20 through wired Internet and is equipped with a content generation module. The content providing server 50 provides content to a content playback device over wireless Internet. The content playback device 10 accesses the content providing server 50 and downloads and plays content.

[22] Examples of the content playback device 10 include a mobile communication terminal, such as a mobile phone or a personal digital assistant (PDA), an audio player, and a multimedia player. For one example, when a personal media player (PMP) is used as the content playback device 10, a user may access the Wired Internet server 70 through the PC 20 and request the Wired Internet server 70 to convert moving images stored in the PC 20 so that the user can play the moving images in the PMP. The Wired Internet server 70 converts or encodes the moving images uploaded from the PC 20 by means of the content generation module and downloads the converted or encoded moving images to the PC 20. The user can connect the PMP to the PC 20, download the moving images to the content playback device, and play the moving images.

[23] For another example, the user may access the Wired Internet server 70 through the

PC 20 and request the Wired Internet server 70 to convert moving images stored in the PC 20 so that the user can play the moving images in the mobile communication terminal 10. The Wired Internet server 70 converts or encodes the moving images uploaded from the PC 20 by means of the content generation module, transmits the converted or encoded moving images to the content providing server 50, generates a message containing position information of content stored in the content providing server 50, and transmits the message to the mobile communication terminal 10. For example, the position information may be expressed in a callback URL type and be included in a short message (SMS message). When receiving the message, the user can access the content providing server 50 and download the content by the use of the position information.

[24] For another example, the user may access the wireless Internet server 30 through the mobile communication terminal 10 and request the wireless Internet server 30 to convert images stored in the mobile communication terminal 10. The wireless Internet server 30 converts or encodes the uploaded images by means of the content generation module, transmits the converted or encoded images to the content providing server 50, generates a message containing position information of content stored in the content providing server 50, and transmits the message to the mobile communication terminal 10. For example, the position information may be expressed in a callback URL type and be included in an SMS message. When receiving the message, the user can access the content providing server 50 and download the content by the use of the position information.

[25] For another example, a content generation module may be operated to play moving images stored in the wired Internet server 70 through the mobile communication terminal 10. For example, the wired Internet server 70 converts the respective frames constituting the moving images into still images by means of the content generation module to be played by a playback engine provided in the mobile communication terminal 10 and transmits the still images to the content providing server 50. The content providing server 50 can transmit the still images to the mobile communication terminal 10 in a streaming manner. In this case, the content generation module con- tinuously operates in real time.

[26] FlG. 2 is a block diagram of a content playback device according to an embodiment of the present invention. The content playback device includes a memory unit 500, a license verification unit 130, and a content playback unit 150. The memory unit 500 stores downloaded content. The license verification unit 130 compares license information of a content generation module recorded on the content stored in the memory unit with time information based on a clock of the content playback device in response to a playback command, and outputs a message indicating that a license is illegal when the content is produced in an illegal manner. The content playback unit 150 plays the content stored in the memory unit in response to a play command.

[27] The memory unit 500 for storing the content is a non- volatile permanent memory, such as a flash memory or a hard disk. The license verification unit 130 and the content playback unit 150 can be generally implemented in software form and constitute the controller 100. The content playback unit 150 may be implemented in hardware form to process a vast amount of data. The license verification unit 130 may include an authentication module implemented in hardware form to process authentication information included in the license information. That is, the controller 100 includes a microprocessor including the above-mentioned hardware and the software incorporated in the hardware.

[28] Whenever the content stored in the memory 500 is played, the license verification unit 130 compares the license information of the content generation module included in the content with time information based on the clock of the content playback device, and verifies whether or not the content playback module generating the content has a valid license. The license is a software license of the content generation module generating the content rather than a license of the content. Since the license is verified whenever the content is played, a user who plays content generated by an illegal content generation module will receive a warning message continuously and complain to a content provider. Thus, the content provider who provides the content can verify the license of the content generation module.

[29] The content playback unit 150 is a content playback engine of the content playback device. For example, the content playback unit 150 loads a content file from a memory unit into a temporary memory area according to header information of the content file, loads playback control commands and resources separately, generates and outputs the respective video frames on the respective graphic layers according to the playback control command, and outputs audio frames in synchronization with the video frames. Examples of the above-mentioned content playback engine include a VIS engine provided by the present applicant and a mobile flash engine provided by Macromedia Inc., which are well-known techniques in the art. The playback command inputted to the content playback unit 150 is generally input through a key input unit, such as a keypad 330 or a touch pad. Video information played by the content playback unit 150 is output to a display unit 353, such as a liquid crystal display device or an organic EL display panel, through a display driver 351. Audio information is output to a speaker 373 or an ear speaker through the audio output unit 371. The above-mentioned units for playing digital content are well known in the art.

[30] In another embodiment, the content playback device further includes a content download unit 110 which downloads content, records download time based on a clock of the content playback device on the content, and stores the content in the memory unit. The time information of the content playback device that is compared by the license verification unit 130 may be the download time information which is recorded on the content.

[31] The content may be downloaded through the wireless communication unit 230 that can be accessed over the wireless Internet as shown in FIG. 1 or 2, through a communication interface, such as USB interface, which is connected to the PC, or through a local wireless communication interface, such as Bluetooth.

[32] Since the license information embedded in the content generation module is transmitted to content generated by the content generation module and is compared with the time, especially download time, based on a clock of the content playback device playing the content, it is not possible to fabricate the license information or the clock.

[33] In another embodiment, the content playback device may further include a host notification unit 170 which accesses the license management server 90 and transmits at 1 east part of license information of the content generation module stored in the content when the content is determined by the license verification unit 130 to be invalid. For example, the host notification unit 170 accesses the license management server 90 through wireless Internet and transmits a license period contained in the license information of the content generation module recorded on the content and identification information of the content generation module. The license management server 90 can identify a content provider which uses the content generation module by the use of the identification information. In addition, the license management server 90 refers to the license period information to verify whether or not the content generation module generates an illegal content and updates the license period to acquire a valid license. If the license period is updated, the license management server 90 notifies the content playback device that the content generation module acquires a valid license.

[34] In another embodiment, the controller 100 of the content playback device may further include a license update unit 190 that updates license information stored in content when update information indicating that a license has been updated is received from a license management server. Accordingly, a user playing the content will not receive a warning message that the content is generated by an illegal content generation module.

[35] FlG. 3 is a block diagram of a license management server 90 according to an embodiment of the present invention. The license management server 90 is a typical server computer, and manages license information of a content generation module stored in a license management database 900. The database 900 includes identification information of a content generation module, information concerning the address, name, and contact number of a content provider who purchases the content generation module, and the purchase date and license period of the content generation module.

[36] The license management server 90 includes a network interface 710 for communicating with other computers over a network, and a license monitor unit 730 that receives information concerning content generated by the content generation module whose license period is expired from the content playback device and notifies a user of the content generation module of the expiration of the license period. The license management server 90 may further include an update information notification unit 750 that verifies whether or not the content generation module has updated a license and, if it has updated, transmits information indicating that it has updated to a media update terminal.

[37] FlG. 4 is a flow chart of a license management method of a content generation module according to an embodiment of the present invention. Operations SlOl to S 105 are performed by the content providing server 50, operations S201 to S219 are performed by the content playback device, and operations S301 to S307 are performed by the license management server 90.

[38] The content providing server 50 receives a request for generating a content file from the wireless Internet server 30 or wired Internet server 70 (operation SlOl), and receives an uploaded file and executes a content generation module to encode the file and generate the content file (operation S 103).

[39] License information of the content generation module is recorded on the generated content file (operation S 105). Examples of the license information include identification information and license period information of the content generation module. The license information may be part or all of the license information recorded on the content generation module. Examples of the identification information of the content generation module may include an identification number assigned to each content generation module or an identification number of a content provider using the content generation module. Since the license can be given to each company, the identification number of the content provider may be identification information of the content generation module. Accordingly, the identification information of the content generation module is construed to comprehend such variations in the present specification. The license information may be recorded to be compatible with the syntax of the content, and be coded and recorded to prevent forgery.

[40] The content generated in this manner is downloaded to the content playback device

10 (operation S201). The content may be downloaded through a wireless Internet network, or be downloaded to a personal computer and downloaded to the content playback device 10 through a computer external input/output port. The content playback device 10 records the time when the content is downloaded (operation S203). The time depends on a system clock of the content playback device, thereby preventing the content provider from faking the time. Since the content that is automatically generated is downloaded as soon as it is generated, the download time is suitable as the license information of the content generation module. However, instead of the download time, a predetermined time may be set in relation to the download and playback of the content.

[41] Next, a user operates a keypad to input a content playback command (operation

S205). Information recorded on the content, i.e., the license information of the content generation module and the time information of the content playback device, are compared to verify whether of not the license is valid (operation S209). If the content is generated by the content generation module having a valid license, the content is played (operation S217), and a licensing process is terminated. The above-mentioned process is repeatedly performed whenever the content is played.

[42] If the content is generated by the content generation module having an invalid license, an error message is output (operation S211). For example, a message "the content you are playing is one which is provided by a content provider having an expired license" may be displayed on a liquid crystal display.

[43] Next, the content playback device verifies flag information that is related to notifying a server (operation S213). If the content playback device is set to notify the license management server when an illegal content generation module is detected by a user of the content playback device, the content playback device notifies the license management server when an illegal content generation module is detected (operation S215). In this case, identification information of a content generation module should be notified. In addition, an identification number of the content, such as an identification number of a playback device which plays the content, for example, a phone number, may be notified. Next, the content is played (operation S217), or terminated without playing the content. If it is set to ignore, the content is played (operation S217), or terminated without playing the content.

[44] When the license management server is notified, the license management server records the notified data on the management database (operation S301). The license management server verifies whether or not the license agreement is renewed after generating the content (operation S303). If the license agreement is renewed, the license management server notifies a corresponding terminal that the license agreement is renewed (operation S305). At this time, new license period information, identification information of the content generation module, and encryption key information for encrypting and decrypting the license information may be notified. The above-mentioned information is preferably encrypted and transmitted. This notification is possible since terminal information, such as a phone number, is already acquired in operation S215. In fact, a content playback device having no network function cannot notify the license management server and receive update information. However, a mobile communication terminal or an apparatus equipped with wireless LAN function can notify the license management server and receive update information.

[45] In case the license is not updated, an operator records on the management database that the license is not updated, and may request the content provider to stop using the illegal content generation module or to renew the license agreement by e-mail or the like.

[46] The content playback device receiving the license update information edits the content stored in the memory unit, and updates the license information of an existing content generation module which is recorded on the content. In case the license information is encoded, it is decoded by the use of the encryption key received from the license management server, and encodes and stores the generated encoding information. However, since it is risky to transmit the encryption key through a network, the encoded licensing information may be transmitted from the license management server and the content playback device may replace the licensing information. Since valid license information is newly recorded, a user using the content will not receive a warning message any more.

[47] While the present invention has been described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the present invention as defined by the following claims. Industrial Applicability

[48] The present invention can be applied to a technique of controlling the playback of multimedia content to manage a license of a content generation module.

Claims

[ 1 ] A content playback device comprising : a memory unit that stores downloaded content; a license verification unit that compares license information of a content generation module recorded in the content stored in the memory unit with time information based on a clock of the content playback device, and outputs a message indicating that a license is invalid in response to a playback command; and a content playback unit that plays the content stored in the memory unit in response to the playback command.

[2] The content playback device of claim 1, further comprising a content download unit that downloads content, records download time, which is based on the clock of the content playback device, in the content, and stores the download time in the memory unit, wherein the time information of the content playback device, which is compared by the license verification unit, is the download time information recorded in the content.

[3] The content playback device of claim 1 or 2, further comprising a host notification unit that accesses a license management server to transmit at least part of the license information of the content generation module stored in the content when the content is determined by the license verification unit to be generated in an invalid manner.

[4] The content playback device of claim 3, further comprising a license update unit that updates the license information stored in the content when receiving from the license management server the license information indicating that the license has been renewed.

[5] A content playback method of a content playback device, comprising the operations of: a) downloading and storing content in a memory unit; c) comparing license information of a content generation module recorded in the content stored in the memory unit with time information based on a clock of the content playback device in response to a playback command to verify whether or not the content is generated in a valid manner; d) outputting a message indicating that a license for the content is expired, in case the content is generated in an invalid manner; and e) playing the content stored in the memory unit.

[6] The content playback method of claim 5, further comprising: b) recording download time, which is based on the clock of the content playback device, in the content, wherein the time information of the content playback device, which is compared in operation c), is the download time information recorded in the content.

[7] The content playback method of claim 5 or 6, further comprising accessing a license management server and notifying license expiration information including identification information of the content generation module that generates the content.

[8] The content playback method of claim 7, further comprising receiving license update information from the license management server and changing license information included in the content to updated license period information.

[9] A license management system comprising: a content generation module that generates content including license information of the content generation module; and a license management server that includes a license monitor unit that receives information concerning content generated by a content generation module whose license period is expired from a content playback device and notifies users of the content generation module that the license period is expired.

[10] The license management system of claim 9, further comprising an update information notification unit that verifies whether or not the license of the content generation module is renewed and, if the license is renewed, transmits to a media playback terminal a message indicating that the license is renewed.