KR20170124839A - Method and system for dividing digital content for fixed-length block encryption - Google Patents

Abstract

Disclosed are a method and a system for dividing digital content for fixed-length block encryption. According to embodiments of the present invention, through the content division method, digital content can be encrypted in a fixed-length block without damaging a group of pictures (GOP) in the digital content such as a video. The content division method comprises the steps of: checking digital content; and dividing the digital content into a plurality of content blocks having a fixed length.

Description

[0001] METHOD AND SYSTEM FOR DIVIDING DIGITAL CONTENT FOR FIXED-LENGTH BLOCK ENCRYPTION [0002]

The following description relates to a method and system for partitioning digital content for fixed size block encryption.

Digital watermarking is a technique for concealing a specific mark (hereinafter referred to as a " watermark ") that is not perceptually recognized in digital contents. For example, Korean Patent Application No. 10-2011-0101577 discloses a technique Discloses a video watermarking system using an overlay channel and a method thereof.

Meanwhile, in a server-client environment, digital contents such as moving images can be provided from a server to a client through streaming or downloading. At this time, the streaming manages the digital contents as a plurality of fragmented files in the server, and sequentially transmits the plurality of files to the client according to the streaming protocol, so that the digital contents are provided to the clients in such a manner that the clients reproduce the transferred files . In the conventional technique of providing digital contents by such a streaming method, digital contents provided to each user can be identified for each user through a combination of files having different watermarks inserted therein. At this time, in the streaming method, if the client can only receive data capable of reproducing digital contents at present, there is not a problem in the download speed.

On the other hand, in the digital content downloading method, a completed file for the digital contents must be stored in the client. Therefore, in the digital contents downloading method, there is a problem about the download speed in which the client must download the entire file as quickly as possible. For example, a video having a playback time of 1 hour may be considered. In this case, when a video is provided in a streaming manner, it is necessary to provide the files at a rate that does not cause the video to be reproduced within 1 hour of the playback time. On the other hand, in the downloading method, You must provide it quickly.

In addition, digital contents such as moving pictures are generally composed of a plurality of GOPs (Group of Pictures) in which a plurality of frames are grouped together. Such a GOP is used as a minimum unit that can be reproduced. Since the GOP has a posterior relationship between frames, if the GOP is damaged or interrupted, the video itself is broken. Therefore, in general, when encrypting such digital contents using DRM (Digital Rights Management), encryption is performed in units of GOP because of the above reasons.

However, due to a particular reason or requirement, there is a need to encrypt with fixed-length blocks rather than GOP-based encryption. Since the GOPs are different in size from each other, there is a problem that the GOP is damaged when encryption is performed with a fixed size block.

The present invention provides a method and system for quickly providing a digital content that is hidden by a user unique identifier in a server-client environment in a downloading manner.

There is provided a method and system for encrypting digital contents into a fixed size block without damaging a group of pictures (GOP) in digital contents such as moving pictures.

A content dividing method comprising: checking digital contents including video data and audio data composed of a plurality of GOP (Group of Pictures) blocks; And dividing the digital content into a plurality of content blocks having a fixed-length, wherein each of the plurality of GOP blocks has a size equal to or less than the fixed size, Wherein the first content block is generated by combining the first portion of the audio data with the first GOP block when the size of the first GOP block is less than the fixed size, Provides a partitioning method.

A computer-implemented content segmentation system, comprising: at least one processor implemented to execute instructions readable by the computer, the at least one processor comprising: video data comprised of a plurality of Group of Pictures (GOP) blocks; Wherein the digital content is divided into a plurality of content blocks having a fixed-length, each of the plurality of GOP blocks having a size equal to or less than the fixed size, Wherein the at least one processor is configured to combine the first portion of the audio data with the first GOP block to divide the digital content into a plurality of GOP blocks if the size of the first GOP block is less than the fixed size, And a first content block having a fixed size is generated. .

It is possible to quickly provide the digital content that is hidden by the user unique identifier in the server-client environment as a download method.

Digital content can be encrypted into a fixed size block without compromising the GOP (Group of Pictures) in digital content such as video.

1 is a diagram illustrating an example of a network environment according to an embodiment of the present invention.
2 is a block diagram illustrating an internal configuration of an electronic device and a server according to an embodiment of the present invention.
3 is a block diagram illustrating an example of components that a processor of a server may include in one embodiment of the present invention.
4 is a flowchart illustrating an example of a method that a server according to an embodiment of the present invention can perform.
5 is a block diagram illustrating an example of components that a processor of an electronic device may include in one embodiment of the present invention.
6 is a flowchart showing an example of a method that an electronic apparatus according to an embodiment of the present invention can perform.
FIG. 7 is a diagram illustrating an example of a plurality of copies in which different code values are inserted, according to an exemplary embodiment of the present invention.
8 is a diagram illustrating examples of a virtual file configured for each user in an embodiment of the present invention.
Figure 9 is an illustration of an example of merging successive fragments of the same code value in one embodiment of the present invention.
10 is a diagram illustrating an example of offset information per user in an embodiment of the present invention.
11 is a block diagram illustrating another example of components that a processor of a server may include in one embodiment of the present invention.
12 is a flowchart illustrating another example of a method that a server according to an embodiment of the present invention can perform.
13 is a diagram showing an example of general MP4 contents.
14 is a diagram showing an example of division of digital contents in an embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating an example of a network environment according to an embodiment of the present invention. 1 shows an example in which a plurality of electronic devices 110, 120, 130, 140, a plurality of servers 150, 160, and a network 170 are included. 1, the number of electronic devices and the number of servers are not limited to those shown in FIG.

The plurality of electronic devices 110, 120, 130, 140 may be a fixed terminal implemented as a computer device or a mobile terminal. Examples of the plurality of electronic devices 110, 120, 130 and 140 include a smart phone, a mobile phone, a navigation device, a computer, a notebook, a digital broadcast terminal, a PDA (Personal Digital Assistants) ), And tablet PCs. For example, although FIG. 1 illustrates the shape of a smartphone as an example of the electronic device 110, in embodiments of the present invention, other electronic devices 120 (for example, , 130, 140) and / or servers 150, 160. In addition,

The communication method is not limited, and may include a communication method using a communication network (for example, a mobile communication network, a wired Internet, a wireless Internet, a broadcasting network) that the network 170 may include, as well as a short-range wireless communication between the devices. For example, the network 170 may be a personal area network (LAN), a local area network (LAN), a campus area network (CAN), a metropolitan area network (MAN), a wide area network (WAN) , A network such as the Internet, and the like. The network 170 may also include any one or more of a network topology including a bus network, a star network, a ring network, a mesh network, a star-bus network, a tree or a hierarchical network, It is not limited.

Each of the servers 150 and 160 is a computer device or a plurality of computers that communicate with a plurality of electronic devices 110, 120, 130 and 140 through a network 170 to provide commands, codes, files, Lt; / RTI > devices.

For example, the server 160 may be a file distribution system that distributes an application for a messenger function or an application installation file for playing digital contents to a plurality of electronic devices 110, 120, 130, and 140. In this case, the server 150 may be a content providing system for providing digital contents to the clients installed with the application. For example, the user of the electronic device 1 (110) can access the server (150) via the network (170) using the application installed in the electronic device (110) Can be requested. In this case, the server 150 may transmit the requested digital content to the electronic device 1 (110).

2 is a block diagram illustrating an internal configuration of an electronic device and a server according to an embodiment of the present invention. 2 illustrates an internal configuration of the electronic device 1 (110) and the server 150 as an example of the electronic device. Other electronic devices 120, 130, 140 or server 160 may have the same or similar internal configurations.

The electronic device 1 110 and the server 150 may include memories 211 and 221, processors 212 and 222, communication modules 213 and 223 and input / output interfaces 214 and 224. The memories 211 and 221 may be a computer-readable recording medium and may include a permanent mass storage device such as a random access memory (RAM), a read only memory (ROM), and a disk drive. Here, the ROM and the non-decaying large capacity recording device may be included as separate permanent storage devices separately from the memories 211 and 221. [ The memory 211 and the memory 221 are provided with an operating system and at least one program code (for example, a program installed in the electronic device 1 (110) and used for a browser or an application installed in the electronic device 1 Code) can be stored. These software components may be loaded from a computer readable recording medium separate from the memories 211 and 221. [ Such a computer-readable recording medium may include a computer-readable recording medium such as a floppy drive, a disk, a tape, a DVD / CD-ROM drive, and a memory card. In other embodiments, the software components may be loaded into memory 211, 221 via communication modules 213, 223 rather than a computer readable recording medium. For example, at least one program may be a program installed by a file distribution system (for example, the server 160 described above) that distributes installation files of developers or applications, May be loaded into the memory 211, 221 based on the application described above.

Processors 212 and 222 may be configured to process instructions of a computer program by performing basic arithmetic, logic, and input / output operations. The instructions may be provided to the processors 212 and 222 by the memories 211 and 221 or the communication modules 213 and 223. For example, the processor 212, 222 may be configured to execute a command received in accordance with a program code stored in a recording device, such as the memory 211, 221.

The communication modules 213 and 223 may provide functions for the electronic device 1 110 and the server 150 to communicate with each other through the network 170 and may provide functions for communicating with other electronic devices (for example, the electronic device 2 120) Or to communicate with another server (e.g., server 160). For example, when the processor 212 of the electronic device 1 110 receives a request (for example, a request for a video call service) generated according to a program code stored in a recording device such as the memory 211, To the server 150 via the network 170 in accordance with the < / RTI > Conversely, control signals, commands, contents, files, and the like provided under the control of the processor 222 of the server 150 are transmitted to the communication module 223 of the electronic device 110 via the communication module 223 and the network 170 213 to the electronic device 1 (110). For example, control signals and commands of the server 150 received through the communication module 213 may be transmitted to the processor 212 or the memory 211, May be stored as a storage medium that may further include a < RTI ID = 0.0 >

The input / output interfaces 214 and 224 may be means for interfacing with the input / output device 215. For example, the input device may include a device such as a keyboard or a mouse, and the output device may include a device such as a display for displaying a communication session of the application. As another example, the input / output interface 214 may be a means for interfacing with a device having integrated functions for input and output, such as a touch screen. More specifically, the processor 212 of the electronic device 1 (110) uses the data provided by the server 150 or the electronic device 2 (120) in processing commands of the computer program loaded in the memory 211 A service screen or contents can be displayed on the display through the input / output interface 214. [

Also, in other embodiments, electronic device 1 110 and server 150 may include more components than the components of FIG. However, there is no need to clearly illustrate most prior art components. For example, electronic device 1 110 may be implemented to include at least a portion of input / output devices 215 described above, or may be implemented with other components such as a transceiver, Global Positioning System (GPS) module, camera, Elements. More specifically, when the electronic device 1 (110) is a smart phone, it may be an acceleration sensor, a gyro sensor, a camera, various physical buttons, buttons using a touch panel, input / output ports, It is to be understood that the present invention may be embodied in various forms without departing from the spirit or scope of the invention.

FIG. 3 is a block diagram illustrating an example of a component that a processor of a server may include in an embodiment of the present invention. FIG. 4 is a block diagram of a method that a server can perform according to an embodiment of the present invention. Fig.

As shown in FIG. 3, the processor 222 included in the server 150 includes components such as a content management unit 310, a transmission / reception unit A control unit 320, a virtual file construction unit 330, and an information generation unit 340. The components of the processor 222 and the processor 222 may control the server 150 to perform the steps 410 to 480 included in the content providing method of FIG. At this time, the components of the processor 222 and the processor 222 may be implemented to execute instructions according to the code of the operating system and the code of at least one program that the memory 221 contains. The components of processor 222 may be representations of different functions of processor 222 performed by processor 222 in accordance with control instructions provided by the program code stored in server 150 have. For example, the content manager 310 may be used as a functional representation of the processor 222 that controls the server 150 to allow the processor 222 to manage digital content in accordance with the control commands described above.

At step 410 the processor 222 may read the necessary commands from the loaded memory 221 with instructions associated with the control of the server 150. [ In this case, the read command may include instructions for controlling the processor 222 to execute steps 420 to 480 to be described later.

In operation 420, the content management unit 310 may manage a plurality of copies of digital contents, each of which has a different code value inserted therein. For example, the content management unit 310 may control the server 150 to store and manage a plurality of copies of the digital content in the storage of the server 150. [ At this time, different code values may be embedded in a plurality of copies so that they can not be visually recognized using watermarking technology. Such a watermarking technique is characterized in that watermark detection is possible even when the digital content is deformed, such as digital-analogue or analog-digital transformation, size conversion, and partial region trimming. Here, the watermarking technique for inserting the code value into the digital content is already well known, and a detailed description thereof will be omitted. The code value can be composed of various types of values selected as needed, such as a number, a combination of numbers such as '123', '456', a letter such as an alphabet, a combination of characters, a combination of letters and numbers. As a simple example, a first copy in which a code value of '0' is inserted and a second copy in which a code value of '1' is inserted can be managed for one digital content.

In step 430, the transmission / reception control unit 320 may receive a client download request for digital content. Here, the client may refer to an application installed in the electronic device 1 (110) or the electronic device 1 (110) accessing the server (150) through the network (170). For example, the user can access the server 150 using the electronic device 1 110, and the user can access the server 150 through the user interface provided by the server 150 (for example, To download the digital content to the server 150. In this case, the transmission / reception control unit 320 may control the server 150 to receive a download request signal from the electronic device 1 (110) accessed through the network (170).

In step 440, the virtual file construction unit 330 combines the portions of the plurality of copies so that the combination of the different code values is matched with the unique identifier of the user identified in association with the client, So that a virtual file for digital contents can be constructed. At this time, the parts constituting each virtual file may have the same size. Also, some portions may be merged with each other according to the conditions described below.

In one embodiment, the virtual file constructor 330 may combine portions of the plurality of copies such that a combination of different code values has a value corresponding to the unique identifier of the user at a location of at least a portion of the virtual file have. For example, assume that the value when the user's unique identifier is represented by a binary string is "010100010001 ". In this case, the first piece of a copy having the code value of '0', which is the first value of the binary string, may be used in the first part for constituting the virtual file. Also, a second piece of the copy having a code value of '1', which is the second value of the binary string, can be used in the second part for constructing the virtual file, and similarly, a third piece , A third piece of the copy having a code value of '0', which is the third value of the binary string, may be used. At this time, the virtual file can be constituted by the number of parts of the number of the binary string. Alternatively, the virtual file may consist of a greater number of parts than the number of digits in the binary string of digits. For example, a pseudo file may consist of parts of a multiple of the digits of a binary string. In this case, a unique identifier represented by a binary string can be used repeatedly. Alternatively, a virtual file may be generated such that code values of a predetermined portion of the virtual file correspond to a unique identifier of the user.

In another embodiment, the virtual file construction unit 330 may combine different code values to generate a unique value for a download request, and may manage the unique value by matching with a unique identifier of the user. For example, the virtual file construction unit 330 may configure a virtual file such that a combination of code values of a virtual file always has a unique value. At this time, the unique value which is a unique value and the unique identifier of the user are matched and stored and managed, so that the user can be identified through the virtual file.

In operation 450, the information generating unit 340 may generate offset information for identifying the location information of the configured virtual file and each of the combined parts of the plurality of copies. The location information may include information about a location for a client to search for a virtual file on the network, and may include a uniform resource locator (URL) generated for a virtual file, for example.

The offset information may be, in one embodiment, information for identifying which part of the copy matches the unique identifier of the user. For example, portions that match a unique identifier may be identified through a particular byte-range of the total bytes of the copy. As a more specific example, it can be assumed that the digital content has a size of 200 bytes. At this time, the offset information includes a portion of the first copy that matches the unique identifier of the user using the byte-range, such as a portion of the range of the first copy and a portion of the range of 100-199 bytes of the second copy, And may include information for identifying the partial authorization.

The offset information may, in another embodiment, be configured to include a chunk number. For example, each of the plurality of copies may be divided into a plurality of chunks. At this time, the offset information may include a chunk number of the corresponding part as information for identifying which part of the copy matches the unique identifier of the user.

In addition, the virtual file configuration unit 330 may combine successive portions having the same code value among the combined portions in Step 440 into a single portion. For example, if three pieces having a code value of '0' are arranged consecutively, the virtual file construction unit 330 may merge the three pieces into one piece having a code value of '0' . In this case, the offset information may include information for identifying the merged portion as one portion. For example, if three pieces with a code value of '0' are identified as byte-ranges of '0-99', '100-199', and '200-299', respectively, Quot; 0-299 " byte-range. In other words, by merging consecutive portions having the same code value and transferring them as one piece, the number of pieces of pieces can be reduced by keeping the pieces of electronic device 1 (110) to be downloaded at a time as large as possible, .

In step 460, the transmission / reception control unit 320 may provide the generated location information and offset information to the client. For example, the transmission / reception control unit 320 may control the server 150 to transmit the data including the position information and the offset information to the electronic device 110 through the network 170.

In step 470, the transmission / reception control unit 330 may receive a download request based on the location information from the client and including offset information. For example, the transmission / reception control unit 320 may control the server 150 to receive a download request signal including offset information from the electronic device 1 (110) accessing via the network 170 based on the location information . At this time, since the electronic device 110 actually requests a part of data for a plurality of copy files, the electronic device 110 may request downloading for each piece. Accordingly, a number of download requests may be generated as many as the number of pieces included in the virtual file. As described above, successive portions having the same code value can be merged and transmitted as a single piece. Therefore, in this case, the number of download requests can be reduced and the download speed can be increased.

In step 480, the transmission / reception control unit 330 may transmit portions corresponding to the offset information from the plurality of copies to the client as a virtual file identified through the location information. For example, the server 150 can identify the virtual file based on the location information used by the electronic device 110 to access it, and can use the offset information included in the download request to identify, 1 (110). At this time, the transmission / reception control unit 330 may control the server 150 to transmit each part of the plurality of identified copies as a virtual file to the electronic device 1 (110) via the network (170).

The virtual file transferred to the electronic device 110 may be stored in the form of a file in the electronic device 110 and may be reproduced in the electronic device 110 or transferred to another device. At this time, since the virtual file includes information for recognizing the unique identifier of the user of the electronic device 1 (110), it is possible to prove ownership of the digital content and to track the user like the initial distributor.

FIG. 5 is a block diagram illustrating an example of a component that a processor of an electronic device may include in an embodiment of the present invention. FIG. 6 is a block diagram of an electronic device according to an exemplary embodiment of the present invention Fig. 2 is a flowchart showing an example of a method. Fig.

5, the processor 212 included in the first electronic device 110 may include a download request unit 210 as a component, and the first electronic apparatus 110 may implement a content providing system according to an embodiment of the present invention. (510), a transmission / reception control unit (520), and a reproduction control unit (530). The components of the processor 212 and the processor 212 may control the electronic device 1 110 to perform the steps 610 to 660 included in the content providing method of FIG. At this time, the components of the processor 212 and the processor 212 may be implemented to execute instructions according to the code of the operating system and the code of at least one program that the memory 211 contains. Herein, the components of the processor 212 are representations of different functions of the processor 212 performed by the processor 212 in accordance with instructions provided by the program code stored in the electronic device 110 . For example, the download request portion 510 may be used as a functional representation of the processor 212 that controls the electronic device 1 110 to cause the processor 212 to request a download in accordance with the instructions described above.

At step 610, the processor 212 may read the necessary commands from the loaded memory 211 with instructions associated with control of the electronic device 110. [ In this case, the read command may include instructions for controlling the processor 212 to execute the steps 620 to 660 to be described later.

In step 620, the download request unit 510 may request downloading of digital content to the server 150, which manages a plurality of copies, into which different code values are inserted, for the digital contents. For example, the download request unit 510 accesses the server 150 through the network 170 to request the download of the specific digital content through the interface provided by the server 150, It is possible to control the device 1 (110). 3 and 4, the server 150 manages a plurality of copies in which different code values are inserted, and stores a virtual file including information for recognizing the unique identifier of the user of the electronic device 1 (110) To the electronic device 1 (110).

In step 630, the transmission / reception control unit 520 receives from the server 150 the location information of the virtual file in which the parts of the plurality of copies are combined and the offset information for identifying each of the combined parts in the plurality of copies, Lt; / RTI > For example, the transmission / reception control unit 520 may control the electronic device 1 (110) so that the position information is received from the server 150, including the offset information.

As described above, the virtual file can be generated by combining parts of a plurality of copies such that a combination of different code values in the server matches the unique identifier of the user as described above. In addition, the location information may include information about a location for a client to search for a virtual file on the network, and may include, for example, a uniform resource locator (URL) generated for a virtual file. The offset information may include a byte-range or a chunk number as information for identifying which part of the copy matches the unique identifier of the user.

In step 640, the download request unit 510 may transmit a download request including offset information based on the location information. For example, the download request unit 510 may control the first electronic device 110 to transmit a download request signal via the network 170 according to the location information. At this time, since the fragments included in the virtual file are included in a plurality of substantially different copies as described above, the download request can be made as many as the number of fragments included in the virtual file.

As described with reference to FIGS. 3 and 4, the server 150 receiving the download request transmits the virtual file corresponding to the location information to the first electronic device 110, And transmits the virtual file to the electronic device 1 (110).

In step 650, the transmission / reception control unit 520 may receive a combination of parts corresponding to the offset information in the plurality of copies as a virtual file identified through the location information. For example, the transmission / reception control unit 520 may control the electronic device 1 (110) so that the server 150 receives the virtual file transmitting the network 170. When all the pieces corresponding to the offset information are combined, data corresponding to one digital content can be obtained as a virtual file, and the electronic device 1 (110) Of storage.

In step 660, the reproduction control unit 530 can reproduce the stored virtual file. For example, the playback control unit 530 may control the first electronic device 110 to display and reproduce a virtual file stored in the storage and display the first virtual file on the display of the first electronic device 110.

Hereinafter, more specific examples for providing the digital content in which the information corresponding to the unique identifier of the user is inserted in a downloading manner will be described.

FIG. 7 is a diagram illustrating an example of a plurality of copies in which different code values are inserted, according to an exemplary embodiment of the present invention. Figure 7 shows n copies (C1, C2, C3, ..., Cn) for one digital content. It is assumed that the digital content has a size of 1200 bytes (0-1199 bytes-range), so that n copies (C1, C2, C3, ..., Cn) also each have a size of 1200 bytes. In addition, a code value '0', a code value '1', a code value '2', and a code value 'n-1' are added to each of the n copies C 1, C 2, C 3, Is inserted. As described above, code values can be implemented in various forms, such as numbers, letters, combinations of numbers, combinations of letters, or combinations of numbers and letters.

The content management unit 310 described above can manage such copies in step 420. The copies may be stored in the server 150, but may be stored in a separate device that communicates with the server 150 via the network 170, as needed.

8 is a diagram illustrating examples of a virtual file configured for each user in an embodiment of the present invention. FIG. 8 shows an example in which virtual files are configured using three copies C1, C2, and C3 so as to match the unique identifiers of the three users U1, U2, and U3. At this time, it can be seen from FIG. 7 that the unique identifier of the user U1 is "012220022011 ", or the value is stored in the server 150 by matching with the unique value" 012220022011 ". Further, it can be known that the unique identifier of the user U2 is " 111022211100 ", or the value stored in the server 150 is matched with "111022211100 ". Likewise, the unique identifier of the user U3 can be found to be "221122012000" or a value stored in the server 150 matching "221122012000".

For example, assume that the unique identifier of user U1 is "012220022011 ". At this time, the server 150 may combine the parts that match the unique identifier "012220022011" of the user U1 from the three copies C1, C2, and C3. In other words, the server 150 divides the portion of the range 0-99 bytes-from the copy C1 having the code value '0' according to the first value '0' of the unique identifier of the user U1 into the first piece 810 of the virtual file, . ≪ / RTI > In addition, the server 150 converts the portion of the range from 100-199 bytes to the second piece 820 of the virtual file from the copy C2 having the code value '1' according to the second value '1' of the unique identifier of the user U1 Can be matched. The server 150 again matches the portion of the 200-299 byte-range from the copy C3 having the code value '2' to the third piece 830 of the virtual file according to the second value '2' of the unique identifier of the user U1 can do. By repeating this process for all values of the unique identifier "012220022011" of the user U1, a virtual file having a unique identifier for the user U1 can be constructed. A virtual file for user U2 and a virtual file for user U3 may also be constructed in a similar manner.

Depending on the embodiment, as already explained, successive fragments having the same code value may be merged into a single fragment. For example, in FIG. 8, it can be seen that the virtual file of user U1 has three pieces of the third piece 830, the fourth piece 840 and the fifth piece 850 having the same code value '2' .

Figure 9 is an illustration of an example of merging successive fragments of the same code value in one embodiment of the present invention. FIG. 9 shows an example of merging successive portions having the same code value in the virtual files of FIG. 8 into one portion. For example, in the virtual file for user U1, the first piece 910 and the second piece 920 exist as one piece because they have the same code value and do not have consecutive pieces. On the other hand, the three pieces 830, 840 and 850 described in FIG. 8 can be merged into one piece 930 as shown in FIG. 9 as successive pieces having the same code value '2'. In the case of using the virtual file of FIG. 8, the user U1 has to proceed with 12 download requests and 12 downloads. However, when the virtual file of FIG. 8 is used, since the user U1 only needs 7 download requests and 7 downloads, It is possible to insert the unique identifier into the virtual file and improve the downloading speed.

10 is a diagram illustrating an example of offset information per user in an embodiment of the present invention. For example, in FIG. 10, the first piece 910 constituting the virtual file of the user U1 has a byte-range of 0 to 99, the second piece 920 has a byte-range of 100 to 199, Th piece 930 has a byte-range of 200 to 499 bytes. A byte-range for each of these fragments may be provided to the corresponding users as offset information. Conversely, users can download necessary pieces from the server 150 based on the provided offset information. For example, if the user U1 requests the server 150 to download a piece of byte-range offset information of '0 to 99', the server 150 obtains the first value of the user's unique identifier "012220022011" Quot; 0 ", it is possible to provide the user U1 with data in the range of '0 to 99' bytes from the copy C1 of the code value '0'. When the user U1 again requests the server 150 to download the fragment including the byte-range offset information of '100 to 199', the server 150 determines that the second value of the user's unique identifier "012220022011 &Quot;, it is possible to provide the user U1 with the byte-range data of '100 to 199' in the copy C2 of the code value '1'. Similarly, when the user U1 requests the server 150 to download a piece including offset information of byte-range of '200 to 499', the server 150 sets the second value of the user's unique identifier "012220022011" Range data of '200 to 499' in the copy C3 of the code value '2' can be provided to the user U1 because it knows that the third and fourth values are '2'. By repeating this process, a virtual file for the user U1 can be provided to the user U1.

There is a need to divide digital content into pieces of equal size, as in the embodiments described above. However, when digital contents including video data composed of a plurality of GOP (Group of Pictures) blocks are divided into a fixed-length, there is a possibility that the GOP is damaged as described above. In addition to the above-described embodiments, there is also a need to divide and encrypt digital content into fixed sizes according to special requirements. Hereinafter, a content dividing system and a content dividing method for dividing digital contents into fixed sizes without damaging the GOP will be described.

FIG. 11 is a block diagram illustrating another example of a component that a processor of a server may include in an embodiment of the present invention. FIG. 12 is a diagram illustrating a method that a server can perform according to an embodiment of the present invention Fig.

In this embodiment, the server 150 may implement a content division system. As shown in FIG. 11, the processor 222 included in the server 150 includes a digital content checking unit 1110, A content encryption unit 1120, and a content encryption unit 1130. In addition, the content management unit 310, the transmission / reception control unit 320, the virtual file configuration unit 330, and the information generation unit 340 described above with reference to FIG. 3 and FIG. The components of the processor 222 and the processor 222 may control the server 150 to perform the steps 1210 to 1240 included in the content division method of FIG. At this time, the components of the processor 222 and the processor 222 may be implemented to execute instructions according to the code of the operating system and the code of at least one program that the memory 221 contains. The components of processor 222 may be implemented in different functions of processor 222 that are performed by processor 222 in accordance with control commands provided by the program code stored in server 150. [ Expressions.

At step 1210, the processor 222 can read the necessary commands from the loaded memory 221 with instructions associated with the control of the server 150. [ In this case, the read command may include an instruction to control the processor 222 to execute steps 1220 to 1240 to be described later.

In step 1220, the digital content check unit 1110 can check the digital content including the video data and the audio data, which are composed of a plurality of GOP (Group of Pictures) blocks. As described above, digital contents such as moving pictures can be generally composed of a plurality of GOPs (Group of Pictures) in which a plurality of frames are grouped together and further include audio data for audio reproduction. The digital content verification unit 1110 can confirm the digital contents to be divided among the digital contents. For example, the digital content verification unit 1110 may control the server 150 to search digital content to be divided among the digital contents stored in the storage of the server 150. [

In step 1230, the content divider 1120 may divide the digital content into a plurality of content blocks having a fixed-length. At this time, at least some blocks of the plurality of GOP blocks may have different sizes, and each of the plurality of GOP blocks may have a size smaller than the fixed size. In other words, the fixed size that the content block has can be set to have a larger size than the largest GOP block among the plurality of GOP blocks. At this time, when the size of the first GOP block among the plurality of GOP blocks is less than the fixed size, the content dividing unit 1120 generates the first content block of a fixed size by combining the first portion of the audio data with the first GOP block . In video content such as video, audio is composed of several packets, and since there is no subsequent association between packets, the audio block has no effect on the overall playback even if it is divided in the middle. In addition, since the size of a damaged packet is very small even if it is divided in the middle, there is not much difference in terms of a user playing digital contents. In other words, in this embodiment, the GOP blocks are first filled in one content block, and the GOP blocks of different sizes are damaged by combining the first part, which is at least a part of the audio block, in the remaining part of the content block, It is possible to divide the digital content.

If the size of the first block is a fixed size, the content divider 1120 may generate the first GOP block as a first content block having a fixed size in step 1230. In other words, in the case of a GOP block which is not to be damaged by the segmentation, the GOP block can be directly used as a content block.

The audio data may be composed of a plurality of audio blocks. In this case, the first portion of the above-described audio data may be at least a part of the first audio block corresponding to the first GOP block. For example, in general MP4 audio / video blocks, GOP blocks and audio blocks corresponding to the respective GOP blocks are sequentially arranged to constitute digital contents. At this time, if the size of the first GOP block is less than the fixed size, a fixed size content block may be generated through the combination of the first GOP block and the first portion, which is a part of the first audio block.

At this time, the content division unit 1120 generates a second block by combining a second part of the first audio block excluding the first part and a second GOP block among the plurality of GOP blocks, If the combined size of the two GOP blocks is less than the fixed size, the third portion of the audio data may be further combined to create a second block of fixed size. Here, the third portion of the audio data may be at least a portion of the audio block corresponding to the second GOP block.

If the combined size of the second portion and the second GOP block is equal to or larger than the fixed size, the content divider 1120 combines the second-1 portion, which is a portion of the second portion, with the second GOP block, Two blocks can be generated.

As described above, the server 150 can divide the digital content into the fixed-size content blocks through the combination of the GOP block and the audio data.

In operation 1240, the content encryption unit 1130 may encrypt the digital content in units of content blocks divided into a fixed size. For example, in the preceding embodiments, digital content is composed of a combination of pieces of the same size, thereby providing digital content that is hidden by a user's unique identifier in a server-client environment. In this case, encryption for DRM or the like needs to proceed in units of pieces of the same size, that is, a unit of a fixed-size (e.g., N-byte) content block. Accordingly, the server 150 divides the digital content according to the content division method described above, thereby dividing and encrypting the digital content with a fixed size without damaging the GOP.

13 is a diagram showing an example of general MP4 contents. 13 shows an example of a part of digital contents in which a plurality of audio blocks 1310, 1330, and 1350 and a plurality of GOP blocks 1320, 1340, and 1360 are sequentially arranged. At this time, it can be seen that the sizes (byte units) of the plurality of audio blocks 1310, 1330, and 1350 and the plurality of GOP blocks 1320, 1340, and 1360 are different from each other. At this time, the dotted boxes 1370, 1380, and 1390 divide the digital contents into a fixed size (200 bytes), and the first GOP block 1320 and the second GOP block 1340 may be damaged . If the GOP block is damaged as described above, the image itself may be broken when the digital content is reproduced.

14 is a diagram showing an example of division of digital contents in an embodiment of the present invention. 14 shows a first content block 1370 divided by a first dotted line box 1370 by combining 180 bytes of the first GOP block 1320 and 20 bytes of a first portion 1410 which is a part of the first audio block 1310. [ Is generated.

14 is a block diagram illustrating an example in which a first audio block 1310 is divided into a second dotted line box 1380 through a combination of 30 bytes of the second portion 1420 and 105 bytes of the second GOP block 1340 2 content block is generated. The third portion 1430 of the second audio block 1330 is further coupled to the second audio block 1330 because the 30 bytes of the second portion 1420 and the 105 bytes of the second GOP block 1340 are combined, So that the second content block can be completed.

Similarly, the second audio block 1330 is divided into a third dotted line box 1390 through the combination of the remaining 12 bytes of the fourth portion 1440 and the 82 bytes of the third GOP block 1360, The creation of a content block may be attempted. Since the 12 bytes of the fourth part 1440 and the 82 bytes of the third GOP block 1360 are combined, the third audio block 1350 corresponding to the third GOP block 1360 is less than the fixed size of 200 bytes. May be further combined for the generation of the third content block. However, since 12 bytes of the fourth portion 1440, 82 bytes of the third GOP block 1360, and 44 bytes of the third audio block 1350 are combined, the size of the next GOP block or the next audio A combination for at least a portion of the block may be considered. For example, if the size of the next GOP block is 62 (200- (12 + 82 + 44)) bytes or less, the next GOP block may be further combined for generation of the third content block. However, if the size of the next GOP block exceeds 62 bytes, at least a portion of the next audio block may be further combined for the generation of the third content block.

As described above, the server 150 may divide the digital content (or each of the plurality of copies of the digital content) into the fixed size content blocks so that one GOP block is not damaged. A code value may be inserted in the divided content blocks to hide the unique identifier of the user, and the divided content blocks for each of the plurality of copies of the digital content may be combined to form a virtual file. Also, encryption for DRM or the like can be performed in units of a fixed-size content block.

In addition, the above-described embodiments explain that the digital content is divided into fixed-size content blocks so that the GOP block is not damaged. At this time, the digital contents may be divided into multiples of a fixed size. For example, in the embodiments shown in FIGS. 13 and 14, the digital content is divided into a fixed size of 200 bytes. However, the digital content may be divided into 400 bytes, 600 bytes, 800 bytes, Lt; / RTI > For example, if a particular content block is forced to be split into more than 512 bytes, the server 150 divides the digital content into a fixed size (512 * N) (where N is a natural number) Lt; RTI ID = 0.0 > of < / RTI > In other words, in the embodiments of the present invention, the size of the content block may be a multiple of a predetermined fixed size. In this case, audio blocks may be included in the remaining area after the video blocks are included so that the GOP is not damaged in the content block.

As described above, according to the embodiments of the present invention, it is possible to rapidly provide the digital content that has been stored with the user's unique identifier in the server-client environment as a download method. In addition, it is possible to encrypt digital contents into a fixed size block without damaging the GOP (Group of Pictures) in digital contents such as moving pictures.

The system or apparatus described above may be implemented as a hardware component, a software component or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA) , A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (20)

A content division method comprising:
Identifying digital content including video data and audio data composed of a plurality of GOP (Group of Pictures) blocks; And
Dividing the digital content into a plurality of content blocks having a fixed-length
Lt; / RTI >
Wherein each of the plurality of GOP blocks has a size equal to or smaller than the fixed size,
Wherein the dividing step comprises:
And generating the first content block of the fixed size by combining the first portion of the audio data with the first GOP block when the size of the first GOP block is less than the fixed size
Wherein the content distribution method comprises the steps of: The method according to claim 1,
Wherein the dividing step comprises:
And generating the first GOP block as a first content block of the fixed size when the size of the first GOP block is the fixed size
Wherein the content distribution method comprises the steps of: The method according to claim 1,
Wherein the audio data is composed of a plurality of audio blocks,
Wherein the first portion is at least a portion of a first audio block corresponding to the first GOP block. The method of claim 3,
Wherein the dividing step comprises:
A second portion of the first audio block excluding a first portion is combined with a second GOP block of the plurality of GOP blocks to generate a second block, and the second portion and the second GOP block are combined Generating a second block of the fixed size by further combining a third portion of the audio data if the size of the first portion of the audio data is less than the fixed size
Wherein the content distribution method comprises the steps of: 5. The method of claim 4,
Wherein the dividing step comprises:
When the combined size of the second portion and the second GOP block is equal to or larger than the fixed size, the second GOP block is combined with the second-1 portion, which is a part of the second portion, Creating
Wherein the content distribution method comprises the steps of: The method according to claim 1,
Encrypting the digital content in units of content blocks divided by the fixed size
Further comprising the steps of: The method according to claim 1,
Managing a plurality of copies of each of the digital contents with different code values inserted therein;
A combination of the different code values is matched with a unique identifier of a user identified in association with the client in accordance with a client download request for the digital content, Comprising; And
And generating offset information for identifying each of the combined parts in the plurality of copies and providing the offset information to the client
Further comprising:
Wherein the virtual file comprises a combination of a plurality of content blocks generated by dividing each of the plurality of copies into the fixed size. 8. The method of claim 7,
Receiving a download request based on the location information from the client and including the offset information; And
Transmitting portions of the plurality of copies corresponding to the offset information to the client as the virtual file identified through the location information
Further comprising the steps of: 8. The method of claim 7,
Wherein the offset information is information for identifying the combined portions in the plurality of copies, and includes a byte-range occupied by a corresponding portion in the copy. 8. The method of claim 7,
Wherein each of the plurality of copies is divided into a plurality of chunks,
Wherein the offset information is information for identifying the combined parts in the plurality of copies, and includes a chunk number of a corresponding part in the copy. 8. The method of claim 7,
Wherein configuring the virtual file comprises:
And combining the portions of the plurality of copies such that the combination of the different code values has a value corresponding to the unique identifier of the user at a position of at least a part of the virtual file. 8. The method of claim 7,
Wherein configuring the virtual file comprises:
Generating a unique value for the download request by combining the different code values, and managing the unique value by matching with the unique identifier of the user. 8. The method of claim 7,
Wherein configuring the virtual file comprises:
Combining the consecutive portions having the same code value out of the combined portions into a single portion,
Wherein the offset information includes information for identifying the merged portion as a single portion. A computer-readable recording medium having recorded thereon a program for causing a computer to execute the method of any one of claims 1 to 13. A computer-implemented content division system,
At least one processor configured to execute instructions readable by the computer,
Lt; / RTI >
Wherein the at least one processor comprises:
The digital content including video data and audio data composed of a plurality of GOP (Group of Pictures) blocks is confirmed,
Dividing the digital content into a plurality of content blocks having a fixed-length,
Wherein each of the plurality of GOP blocks has a size equal to or smaller than the fixed size,
Wherein the at least one processor is further configured to:
And generating the first content block of the fixed size by combining the first portion of the audio data with the first GOP block when the size of the first GOP block is less than the fixed size
And the content distribution system. 16. The method of claim 15,
Wherein the at least one processor is further configured to:
And generating the first GOP block as a first content block of the fixed size when the size of the first GOP block is the fixed size
And the content distribution system. 16. The method of claim 15,
Wherein the audio data is composed of a plurality of audio blocks,
Wherein the first portion is at least a portion of a first audio block corresponding to the first GOP block. 18. The method of claim 17,
Wherein the at least one processor is further configured to:
A second portion of the first audio block excluding a first portion is combined with a second GOP block of the plurality of GOP blocks to generate a second block, and the second portion and the second GOP block are combined Generating a second block of the fixed size by further combining a third portion of the audio data if the size of the first portion of the audio data is less than the fixed size
And the content distribution system. 19. The method of claim 18,
Wherein the at least one processor is further configured to:
When the combined size of the second portion and the second GOP block is equal to or larger than the fixed size, the second GOP block is combined with the second GOP portion, which is a part of the second portion, Creating
And the content distribution system. 16. The method of claim 15,
Wherein the at least one processor comprises:
Managing a plurality of copies in which different code values are inserted for the digital contents,
A combination of the different code values is matched with a unique identifier of a user identified in association with the client in accordance with a client download request for the digital content, And,
And generating offset information for identifying each of the combined parts in the plurality of copies and providing the offset information to the client,
Wherein the virtual file comprises a combination of a plurality of content blocks generated by dividing each of the plurality of copies into the fixed size.

Images