JP7042567B2 - Distribution of digital content with embedded user-specific information - Google Patents

Description

The disclosure herein relates to improving DRM. The disclosure of the present invention more specifically relates to improvements in the distribution of digital content in which user-specific information is embedded.

DRM (Digital Rights Management) is a technology for restricting unauthorized use of digital contents. There are various methods for DRM.

Social DRM is known as a kind of this DRM. In social DRM, in order to suppress the distribution of digital contents without permission, user-specific information that identifies the purchaser of the digital contents is embedded in the digital contents. As a result, it is possible to identify the user who illegally published the digital content based on the user identification information. In social DRM, being able to identify an unauthorized publisher has the effect of deterring unauthorized disclosure of digital content.

Japanese Unexamined Patent Publication No. 2011-503743 discloses a method of distributing digital contents in which user-specific information is embedded to a user. In the distribution method of the publication, the second file containing the data identifying the user is combined with the first file of the digital content in response to the distribution request from the user, and the combined file is distributed. ..

In the method described in the same gazette, the data of both files are read into the memory in order to combine the second file with the first file of the digital content. This data is deleted from the memory after the combined files have been delivered (see paragraphs [0028], paragraphs [0039], and claim 3 of the same publication).

Japanese Unexamined Patent Publication No. 2011-503743

In the above-mentioned conventional distribution method, in order to embed the user-specific information in the digital content, it is necessary to temporarily store all the data of the digital content in the memory. However, if all the data of the digital contents to be delivered is stored in the memory, the amount of the memory used becomes large.

The process of embedding user-specific information can also be performed on the disk instead of on the memory. However, since the access speed to the disk is significantly slower than the access speed to the memory, if the disk is used as the storage area, the time required for distribution becomes long.

Even if a high-speed memory is used, it takes a long time from the user's request to the start of distribution in the above-mentioned conventional distribution method. That is, in the above-mentioned conventional distribution method, the first file and the second file are combined, and then the combined file is distributed to the user. Therefore, the distribution cannot be started until the file combination is completed, and as a result, it takes a long time from the user requesting the distribution to the start of the distribution.

As described above, in the distribution of digital contents in which user-specific information is embedded, there is an unsolved need to suppress memory consumption and shorten the time until distribution starts.

An object of the present invention is to alleviate or eliminate at least a part of the above problems.

One more specific object of the present invention is to embed user-specific information in digital content with less memory consumption.

Another object of the present invention is to shorten the time from receiving the distribution request of the digital content to the start of distribution.

Other objects of the invention will become apparent by reference to the entire specification.

A system according to an embodiment of the present invention includes one or more computer processors, a memory, and a storage for storing a plurality of compressed digital contents. In one embodiment, the one or more processors divides the data of the specific digital content requested by the user among the plurality of digital contents into a plurality of data by executing a predetermined computer-readable instruction. A unit is generated, the first data unit among the plurality of data units is stored in the memory, the first data unit stored in the memory is expanded, and the first data unit includes an embedded area. When it is determined whether or not the first data unit includes the embedded area, an embedding process is performed in which the user-specific information that identifies the user is embedded in the embedded area of the first data unit.

In one embodiment of the present invention, the embedded region is a region that does not affect the viewing of the specific digital content regardless of the data contained in the embedded region. For example, when the specific digital content is in JPEG format, the COM (Comment) segment used for embedding the annotation text in text format can be used as the embedding area.

In one embodiment of the present invention, the data of the specific digital content includes a data body and metadata of the data body, and the embedded area is a region for storing the metadata. Still image digital content is created and distributed, for example, in PDF format. The PDF format content may be delivered together with an XMP format metadata file containing the metadata of the content. In this case, the PDF format data corresponds to the data body, and the XMP format metadata file corresponds to the metadata of the data body.

According to each of the above embodiments, when embedding user-specific information in the specific digital content requested by the user, not the entire data of the specific digital content but a first data unit that is a part thereof is stored in the memory. Will be done. Then, on the memory, a process of expanding the first data unit and a process of embedding the user-specific information in the first data unit are performed. Therefore, the user-specific information can be embedded with a smaller amount of memory than when the entire digital content data is stored in the memory.

In one embodiment of the invention, the one or more processors compresses the first data unit after the embedding process. When the embedded region is included in the first data unit, the first data unit in which the user-specific information is embedded is compressed. When the embedded region is not included in the first data unit, the first data unit that does not include the user-specific information is compressed.

According to the embodiment, decompression, embedding of user-specific information, and compression (recompression) are performed on the memory for the first data unit which is a part of the data of the specific digital content requested by the user, not the entire data. ) Processing is performed. As a result, the memory consumption required for embedding the user-specific information can be reduced.

In one embodiment of the invention, the one or more processors perform a transmission process for transmitting the compressed first data unit to the user.

According to the embodiment, the first data unit, which is a part of a plurality of data units constituting the specific digital content, can be transmitted to the user. Therefore, even if the decompression and compression processing of the entire data of the specific digital content requested by the user is not completed, the transmission processing of the digital content to the user can be started. As a result, the time required from the distribution request to the start of distribution can be shortened as compared with the conventional distribution method in which the entire content data is decompressed and recompressed before distribution.

In one embodiment of the invention, the one or more processors delete the first data unit from the memory after starting the transmission process of the first data unit.

According to these embodiments, after starting the transmission processing of the user-specific information for the first data unit, the first data unit is deleted from the memory. As a result, the memory consumption can be reduced.

In one embodiment of the invention, the one or more processors is a second data unit that is different from the first data unit of the plurality of data units after the first data unit has been deleted from the memory. Is stored in the memory, the second data unit stored in the memory is expanded, it is determined whether or not the second data unit includes an embedded area, and the embedded area is included in the second data unit. When included, an embedding process is performed in which user-specific information that identifies the user is embedded in the embedded area of the second data unit.

According to the above embodiment, the first data unit is deleted from the memory before the embedding process of the user-specific information in the second data unit is performed on the memory. As a result, the memory consumption can be reduced.

A method according to an embodiment of the present invention is a method realized by one or more processors executing predetermined computer-readable instructions. The method comprises a step of dividing the data of a specific digital content requested by a user among a plurality of digital contents compressed and stored in a storage to generate a plurality of data units, and among the plurality of data units. A step of storing the first data unit in the memory, a step of expanding the first data unit stored in the memory, and a step of determining whether or not the first data unit includes an embedded area. When the first data unit includes the embedded area, the first data unit includes a step of embedding user-specific information for identifying the user in the embedded area of the first data unit.

A program according to an embodiment of the present invention is requested by a user among a plurality of digital contents compressed and stored in a storage in the one or a plurality of processors by being executed by the one or a plurality of processors. A step of dividing the data of the specific digital content to generate a plurality of data units, a step of storing the first data unit among the plurality of data units in a memory, and a step of storing the first data in the memory. The step of extending the unit, the step of determining whether or not the first data unit includes an embedded region, and the step of embedding the first data unit when the first data unit includes the embedded region. The step of performing the embedding process of embedding the user-specific information that identifies the user in the area is executed.

As described above, according to the embodiment of the present invention, the user-specific information can be embedded in the digital content with less memory consumption. Further, according to the embodiment of the present invention, it is possible to shorten the time from receiving the distribution request of the digital content to the start of distribution.

It is a block diagram schematically showing the system which concerns on one Embodiment of this invention. It is a schematic diagram schematically showing an example of the folder structure of the content delivered according to one embodiment of the present invention. It is a schematic diagram schematically showing an example of the data structure of the content delivered according to one embodiment of the present invention. It is a flow diagram which shows the procedure which distributes a content according to one Embodiment of this invention. It is a flow diagram which shows the processing procedure to the data unit by one Embodiment of this invention.

Hereinafter, various embodiments of the present invention will be described with reference to the drawings as appropriate. The same or similar components are designated by the same reference numerals in a plurality of drawings.

FIG. 1 is a block diagram schematically showing a system according to an embodiment of the present invention. The system includes a server 10 and a user terminal 30. The server 10 and the user terminal 30 are connected to each other so as to be able to communicate with each other via the network 20. In FIG. 1, only one user terminal 30 is shown for the sake of brevity. However, as will be apparent to those skilled in the art, the system of FIG. 1 can include as many user terminals 30 as there are users.

The server 10 is a content server for distributing digital contents to the user terminal 30. The server 10 may be configured to be capable of delivering various types of digital content. The digital contents that can be distributed by the server 10 may include still image contents such as electronic books, moving image contents such as movies, music contents such as music, and arbitrary contents other than these. The types of content that can be delivered by the server 10 are not limited to those specified in this specification.

The user terminal 30 is an information processing device used by the user to use the digital contents distributed from the server 10. The user terminal 30 may be a mobile phone, a smartphone, a tablet terminal, a personal computer, an electronic book reader, a wearable computer, a game console, and various information processing devices other than these.

The server 10 includes a processor 11, a memory 12, a user I / F 13, a communication I / F 14, and a storage 15. Each of these components is electrically connected to each other via a bus (not shown). The processor 11 loads various programs into the memory 12 and executes instructions included in the loaded programs.

In FIG. 1, the processor 11 is shown as a single component, but the processor 11 may be a collection of a plurality of physically separate processors. In the present specification, the instruction executed by the processor 11 may be executed by a single processor or may be executed by a plurality of processors in a distributed manner. Instructions executed by processor 11 may be executed by a single or multiple virtual processors.

The memory 12 is used to store instructions executed by the processor 11 and various other data. The memory 12 is a main storage device (main memory) that the processor 11 can access at high speed. The memory 12 is composed of, for example, a RAM such as a DRAM or an SRAM.

The user I / F 13 includes, for example, an information input device such as a keyboard and a mouse that accepts an operator's input, and an information output device such as a liquid crystal display that outputs a calculation result of the processor 11.

The communication I / F14 is implemented as hardware, firmware, communication software such as a TCP / IP driver or PPP driver, or a combination thereof.

The storage 15 is an external storage device accessed by the processor 11. The storage 15 is composed of, for example, a magnetic disk or an optical disk. The access speed when the processor 11 accesses the storage 15 is significantly slower than the access speed when accessing the memory 12. The storage 15 may have a larger capacity than the memory 12. Various data related to the distribution of digital contents are stored in the storage 15. In the storage 15, for example, digital contents for distribution to the user terminal 30 are stored.

The digital content is stored in the storage 15 as coded data in which text, an image, a moving image, a voice, a music, or other digital content is encoded by a predetermined coding method. The coded data of this digital content is compressed in a predetermined compression format. As the compression format, for example, a format using the Deflate compression algorithm is used. In the present invention, for example, the ZIP format is used for compression of digital content.

Various data that can be stored in the storage 15 may be stored in a storage (for example, storage 25) or a database server that is physically separate from the server 10. In FIG. 1, the storage 15 is shown as a single unit, but the storage 15 may be a collection of a plurality of physically separate storages. That is, in the present specification, the data stored in the storage 15 may be stored in a single storage or may be distributed and stored in a plurality of storages. Also, in the present specification and claims, the term "storage" may refer to either a single storage or a collection of multiple storages, as is permitted in the context.

Although the server 10 is shown as a single unit in FIG. 1, the server 10 may be a collection of a plurality of physically separate servers. That is, in FIG. 1, the configuration included in the server 10 may be distributed and provided in a plurality of different servers. Further, the functions executed by the server 10 may be distributed to a plurality of servers and executed. As described above, the server 10 is not limited to a server having a physically single configuration, but can also refer to a collection of physically separate servers.

FIG. 2 shows an example of a file in which digital content data stored in the storage 15 is stored and a folder in which the file is stored. As shown in FIG. 2, various data of digital contents are stored in the content file 50a and the metadata file 50b. The content file 50a and the metadata file 50b are stored in the folder 50. As described above, the content file 50a and the metadata file 50b are compressed in a predetermined compression format such as ZIP.

The content file 50a stores coded data obtained by encoding digital content such as an electronic book by a predetermined coding method. In the present specification, the coded data obtained by encoding the digital content may be referred to as a data body. For example, when the digital content is a still image, the data body of the digital content is coded data obtained by encoding the still image by a predetermined coding method (for example, JPEG).

The data body stored in the content file 50a can be encoded in various formats depending on the type of digital content. For example, when the digital content is an electronic book, the data body of the digital content is JPEG (Joint Photographic Experts Group), PNG (Portable Network Graphics), PDF (Portable Document Form), or other than these. It is coded data encoded by any coding method. When the digital content is video content for streaming distribution, the data body is encoded by AVI (Audio Video Interleave), ASF (Advanced Systems Format), or any other method suitable for video. It is coded data.

The metadata file 50b stores the metadata related to the data body of the digital content stored in the content file 50a. The metadata file is stored in the storage 15 in the XMP (Extensible Metadata Platform) format, for example. The metadata of the digital content stored as the metadata file 50b includes the copyright information of the digital content, the information about the creator, the information about the creation date and time, the information about the creation location, and any other metadata. obtain.

The metadata of the digital content may be stored in the same file as the data body. For example, JPEG-encoded data has a COM (Comment) segment. This COM (Comment) segment is an area for embedding a text-format annotation. Metadata in JPEG format digital content may be stored, for example, in a COM segment. When all the metadata of the digital content is stored in the content file 50a, the folder 50 for the digital content does not have to include the metadata file 50b.

The data body and metadata encoding methods, file formats, and formats specifically referred to herein are merely exemplary and are not limited to those specifically described herein. Rather, the digital content can be encoded by any coding method as long as it does not contradict the gist of the present invention.

Subsequently, the functions of the server 10 and the user terminal 30 according to the embodiment of the present invention will be described. The server 10 according to the embodiment of the present invention can realize various functions described below by executing a computer-readable instruction in the processor 11.

In one embodiment of the present invention, the instructions executed by the processor 11 of the server 10 include a division module 41, an expansion module 42, a determination module 43, an embedded module 44, a compression module 45, and a transmission module 46. , Is included. The instructions that can be executed by the processor 11 are not limited to those specified herein. The division module 41, the decompression module 42, the determination module 43, the embedding module 44, the compression module 45, and the transmission module 46 may be executed by the processor 11 at the same time as other instructions.

By executing the division module 41, the processor 11 executes a specific digital content (hereinafter, "specific digital content") from a plurality of digital contents stored in the storage 15 based on a distribution request from the user terminal 30. ) Is read, and the specific digital content is divided into a plurality of data units. The processor 11 can identify the specific digital content from the plurality of digital contents stored in the storage 15, for example, based on the content ID that identifies the digital content included in the distribution request.

Each of the plurality of data units may have substantially the same data size as each other, or may have different data sizes from each other. Each data unit has, for example, a data size of about 4 MB. When the specific digital content has a data size of 100 MB, the digital content can be divided into 25 data units of about 4 MB each.

FIG. 3 schematically shows the data structure of the divided specific digital contents. As shown in the figure, the data of the specific digital content 60 is divided into n data units of the data unit DU (1) to the data unit DU (n). The data of the specific digital content may include a data body and metadata related to the data body.

By executing the division module 41, the processor 11 stores any one data unit among the data units DU (1) to DU (n) in the memory 12. For example, the data unit DU (1) is stored in the memory 12. The data unit stored in the memory 12 does not have to be the data unit DU (1), and may be a data unit selected from the data units DU (2) to DU (n). Hereinafter, a mode in which the data unit DU (1) is stored in the memory 12 will be described. The data unit DU (1) may include a part or all of the data body of the specific digital content 60, or may be a part or all of the metadata of the specific digital content 60. The data unit DU (1) may include a part of the data body and a part of the metadata of the specific digital content 60.

By executing the decompression module 42, the processor 11 decompresses the data unit DU (1) stored in the memory 12 on the memory 12. As described above, the digital content stored in the storage 15 is compressed by a predetermined compression algorithm. Decompression of the compressed data means returning the digital content to its pre-compressed state using the compression algorithm used to compress the digital content. The data of the decompressed data unit DU (1) is also stored in the memory 12. Data compression and decompression on the memory is realized by using, for example, a library for data compression / decompression such as Zlib.

The processor 11 analyzes the expanded data unit DU (1) expanded on the memory 12 by executing the determination module 43, and embeds the user-specific information in the data unit DU (1). Determine if the embedded area is included.

This embedded area is an area for storing data in the data unit DU (1), which does not affect the viewing of specific digital contents even if data such as text information is embedded. That is, even if the content of the text embedded in the embedded area changes, the specific digital content is also decoded before and after the change. Therefore, even if the content of the text embedded in the embedded area changes, the user can view the same specific digital content.

In one embodiment, the data unit DU (1) includes coded data obtained by encoding digital content. Even if the text information is embedded in the embedded area of the data unit DU (1), the data unit DU (1) is normally decoded. On the other hand, if text information is embedded in a region other than the embedded area of the data unit DU (1), decoding will not be performed normally. That is, even if the data unit DU (1) in which the text information is embedded other than the embedded area is subjected to the decoding process, the content before encoding cannot be obtained.

The embedded region will be further described by taking JPEG as an example. As will be apparent to those of skill in the art, a JPEG-encoded file will contain multiple segments and image data. The segments of the JPEG-encoded file include segments that affect the viewing (display) of the specific digital content (for example, DQT segment, DHT segment, SOF segment) and segments that do not affect the display of the content. (For example, COM segment) and. Among such various segments, a segment that does not affect the display of the specific digital content (for example, a COM segment) is defined as an embedded region. When the data body of the specific digital content has a JPEG format, the processor 11 analyzes the data unit DU (1) according to a known analysis algorithm so that the data unit DU (1) can view (display) the specific digital content. ) Is included or not (for example, a COM segment).

Even when the file format of the data body of the specific digital content is encoded by an encoding method other than JPEG, the specific digital content can have an embedded area that does not affect the viewing of the digital content. Files for the data body of digital contents are often provided with an information description area in which copyright information and other descriptive information can be stored. Copyright information and other information are written in the information description area, for example, in a text format. This information description area does not affect the viewing of digital contents. Therefore, such an information description area can be used as an embedded area.

As described above, the metadata of the specific digital content may be stored in the metadata file 50b. When the data unit DU (1) includes at least a part of the metadata stored in the metadata file 50b, the area in which the metadata is stored can be used as the embedded area.

When the data unit DU (1) includes an embedded area by executing the embedded module 44, the processor 11 embeds the user-specific information that identifies the user in the embedded area of the data unit DU (1). Perform embedding process. When the data unit DU (1) does not include the embedded area, the processor 11 does not perform the embedding process of the user-specific information.

The user-specific information that identifies the user is, for example, a user ID that can uniquely identify the user who requested the distribution of the specific digital content. For example, when a user starts using the content distribution service provided by the server 10, a user ID is issued to the user. The server 10 can manage the user ID in association with other information of the user. For example, the user ID of a user includes attribute information (age, gender, etc.) of the user, payment information (credit card number, etc.) of the user, service usage history (purchase history, download history, viewing history, search) of the user. It is managed by the server 10 together with the history and the like). When the server 10 receives a request from a certain user, the server 10 can respond to the request based on the information associated with the user ID of the user.

The processor 11 may encrypt the user-specific information by a predetermined encryption method and embed the encrypted user-specific information in the embedded area of the data unit DU (1).

The user-specific information applicable to the present invention is not limited to the user ID. The user-specific information applicable to the present invention may include any information that can identify the user.

The processor 11 compresses the data unit DU (1) by executing the compression module 45. The compression of the data unit DU (1) is performed using the same or different compression algorithm as the compression algorithm used for the compression of the specific digital content. For example, when the specific digital content stored in the storage 15 is compressed by the ZIP method, the compression module 45 can also compress the data unit DU (1) by the same ZIP method.

When the user-specific information is embedded in the data unit DU (1), the processor 11 compresses the data unit DU (1) in which the user-specific information is embedded. On the other hand, when the user-specific information is not embedded in the data unit DU (1), the data unit DU (1) in which the user-specific information is not embedded is compressed.

The processor 11 executes the transmission module 46 to perform transmission processing of the compressed data unit DU (1). For example, the processor 11 reads the compressed data unit DU (1) from the memory 12 and transmits it to the user (to the user terminal 30 of the user).

The processor 11 can delete the data unit DU (1) from the memory 12 after the transmission process of the data unit DU (1) is started. The processor 11 can delete the data unit DU (1) from the memory 12 at an arbitrary timing that does not interfere with the transmission of the data unit DU (1) after the start of the transmission process of the data unit DU (1). ..

Each of the above-mentioned processes described with respect to the data unit DU (1) can be similarly performed on any data unit DU (2) to the data unit DU (n) other than the data unit DU (1). For example, after embedding, compressing, and transmitting the user-specific information in the data unit DU (1), the data unit DU (2) is stored in the memory 12 and the user-specific information is embedded in the data unit DU (2). , Compression, and transmission can be performed.

The server 10 can execute various functions other than the above. For example, the server 10 can perform billing processing for the user by executing a predetermined instruction on the processor 11.

Next, with reference to FIG. 4, a method of delivering the specific digital content requested by the user according to the embodiment of the present invention will be described. As shown in FIG. 4, first, in step S11, a content distribution request is received from the user (user terminal 30).

Next, in step S12, the specific digital content (hereinafter referred to as "specific digital content") is selected from the plurality of digital contents stored in the storage 15 based on the distribution request received in step S11. It is read, and the read specific digital content is divided into a plurality of data units. As shown in FIG. 3, the specific digital content is divided into, for example, n data units of the data unit DU (1) to the data unit DU (n). The specific digital content is specified, for example, based on the content ID included in the distribution request. The processing in step 12 is performed, for example, by executing the division module 41 in the processor 11.

Next, in step S13, distribution processing and distribution processing are sequentially performed for each of the data unit DU (1) to the data unit DU (n). For example, first, the distribution process is performed on the data unit DU (1). The distribution process for the data unit DU (1) includes storage of the data unit DU (1) in the memory 12, decompression on the memory 12, embedding of user-specific information, compression (recompression), and user terminal 30. Each process of sending to is included. Details of the distribution process in step S13 will be described later.

When the distribution process for the data unit DU (1) is completed in step 13, the process proceeds to step S14, and it is checked whether or not the distribution process for all the data units is completed. When the distribution process of the data unit DU (1) is completed, the distribution process for the other data units (data unit DU (2) to the data unit DU (n)) is not completed, so the process returns to step S13. .. In step 13, distribution processing is performed for the next data unit (for example, data unit DU (2)). When all the distribution processing for the data unit DU (1) to the data unit DU (n) is completed in step S13, the distribution processing of the specific digital content is terminated. When all the distribution processes for each of the data unit DU (1) to the data unit DU (n) are completed, the distribution of the specific digital content data requested by the user terminal 30 to the user terminal 30 is completed.

The user terminal 30 can construct specific digital contents based on the data unit DU (1) to the data unit DU (n) distributed from the server 10. The user terminal 30 can make the user view the specific digital content by using the software corresponding to the format of the acquired specific digital content.

Subsequently, with reference to FIG. 5, the delivery process in step S13 of FIG. 4 will be described more specifically. FIG. 5 is a flow chart showing a procedure of distribution processing sequentially performed for each of the data unit DU (1) to the data unit DU (n). The distribution process is performed for each of the data unit DU (1) to the data unit DU (n). Here, the distribution process will be described using the data unit DU (1) as an example.

First, in step S21, the data unit DU (1) is stored in the memory 12.

Next, in step S22, the data unit DU (1) stored in the memory 12 is expanded on the memory 12. The decompression of the data unit DU (1) is performed, for example, by the processor 11 executing the decompression module 42.

Next, in step S23, the expanded data unit DU (1) expanded on the memory 12 is analyzed, and whether the data unit DU (1) includes an embedded area for embedding user-specific information. Whether or not it is determined. This determination is performed, for example, by the processor 11 executing the determination module 43.

If the data unit DU (1) includes an embedded area, the process proceeds to step S24. In step S24, an embedding process for embedding user-specific information that identifies a user is performed in the embedding area of the data unit DU (1). This embedding process is performed, for example, by the processor 11 executing the embedding module 44.

On the other hand, if the data unit DU (1) does not include the embedded area, the process proceeds to step S25.

In step S25, the data unit DU (1) is compressed. Specifically, when the user-specific information is embedded in the data unit DU (1), the data unit DU (1) in which the user-specific information is embedded is compressed. On the other hand, when the user-specific information is not embedded in the data unit DU (1), the data unit DU (1) in which the user-specific information is not embedded is compressed. This compression process is performed, for example, by the processor 11 executing the compression module 45.

Next, in step S26, the compressed data unit DU (1) is transmitted to the user terminal 30. This transmission process is performed, for example, by the processor 11 executing the transmission module 46.

Next, in step S27, the data unit DU (1) is deleted from the memory, and the distribution process for the data unit DU (1) is completed.

After the data unit DU (1) is deleted, the distribution process of FIG. 5 is sequentially performed for the other data units (data unit DU (2) to data unit DU (n)).

As described above, according to the above embodiment, the data unit (for example, the data unit DU (1)) which is a part of the data of the specific digital content requested by the user is stored in the memory 12, and the memory is concerned. On step 12, user-specific information is embedded in the data unit. Therefore, the user-specific information can be embedded with a smaller amount of memory than when the entire digital content data is stored in the memory.

According to the above embodiment, the entire data of the specific digital content is not transmitted to the user terminal 30 at once, but is transmitted to the user terminal 30 in units of data units that are a part thereof. Therefore, even if the decompression and compression processing of the entire data of the specific digital content is not completed, the transmission processing of the digital content to the user terminal 30 can be started. As a result, the time required from the distribution request to the start of distribution can be shortened as compared with the conventional distribution method in which the entire content data is decompressed and recompressed before distribution.

The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist thereof.

Further, in the embodiment of FIG. 1, a part or all of the functions executed by the processor 11 may be realized by the processor 31 of the client terminal 30 or the processor of another device as long as it does not deviate from the gist of the invention. , Some or all of the functions of the processor 31 may be executed by the processor 11 of the server 10 or the processor of another device.

In the processing procedure described in the present specification, particularly the processing procedure described using the flow chart, a part of the process (step) constituting the processing procedure is omitted, as a step constituting the processing procedure. It is possible to add steps not specified and / or change the order of the steps, and the processing procedure in which such omissions, additions, and changes are made is not intended to deviate from the gist of the present invention. Included in the scope of the invention.

In the present specification, even if the components of the invention are described as either singular or plural, or even if they are described without limitation to either singular or plural, they should be understood separately in the context. Except for, the component may be singular or plural.

10 Server 11 Processor 12 Memory 15 Storage 30 User terminal 41 Split module 42 Decompression module 43 Judgment module 44 Embedded module 45 Compression module 46 Transmission module

Claims (10)

With one or more computer processors,
With memory
Storage for storing multiple compressed digital contents,
It is a system equipped with
The one or more processors may execute a given computer-readable instruction.
Of the plurality of compressed digital contents, the data of the specific digital content requested by the user is divided to generate a plurality of compressed data units.
The first data unit among the plurality of compressed data units is stored in the memory, and the first data unit is stored in the memory.
The first data unit stored in the memory is decompressed and
It is determined whether or not the first data unit includes an embedded area, and it is determined.
When the embedded area is included in the first data unit, an embedding process for embedding user-specific information that identifies the user in the embedded area of the first data unit is performed.
The data of the specific digital content includes a data body and metadata of the data body.
The embedded area is an area for storing the metadata.
system. The system of claim 1, wherein the one or more processors compresses the first data unit after the embedding process. The system according to claim 2, wherein when the first data unit includes the embedded region, the one or more processors compress the first data unit in which the user-specific information is embedded. 2. The system of claim 2, wherein if the first data unit does not include the embedded region, the one or more processors compresses the first data unit that does not contain the user-specific information. The system according to any one of claims 2 to 4, wherein the one or more processors perform a transmission process for transmitting the compressed first data unit to the user. The system according to any one of claims 1 to 5, wherein the one or a plurality of processors deletes the first data unit from the memory after starting a transmission process for the first data unit. The one or more processors
After the first data unit is deleted from the memory, a second data unit different from the first data unit among the plurality of data units is stored in the memory.
The second data unit stored in the memory is decompressed and
It is determined whether or not the second data unit includes an embedded area, and it is determined.
When the embedded area is included in the second data unit, an embedding process is performed in which the user-specific information that identifies the user is embedded in the embedded area of the second data unit.
The system according to claim 6. The system according to any one of claims 1 to 7, wherein the embedded area is an area that does not affect the viewing of the specific digital content. A method realized by one or more processors executing certain computer-readable instructions.
The process of dividing the data of the specific digital content requested by the user from among the multiple digital contents compressed and stored in the storage to generate multiple compressed data units, and
The step of storing the first data unit among the plurality of compressed data units in the memory, and
The step of expanding the first data unit stored in the memory and
The step of determining whether or not the first data unit includes an embedded area, and
When the first data unit includes the embedded area, the first data unit includes a step of embedding user-specific information for identifying the user in the embedded area of the first data unit .
The data of the specific digital content includes a data body and metadata of the data body.
The embedded area is an area for storing the metadata.
Method. By being executed on one or more processors, the one or more processors
The process of dividing the data of the specific digital content requested by the user from among the multiple digital contents compressed and stored in the storage to generate multiple compressed data units, and
The step of storing the first data unit among the plurality of compressed data units in the memory, and
The step of expanding the first data unit stored in the memory and
The step of determining whether or not the first data unit includes an embedded area, and
When the first data unit includes the embedded area, a step of embedding user-specific information for identifying the user in the embedded area of the first data unit, and a step of performing an embedding process.
Is a program that executes
The data of the specific digital content includes a data body and metadata of the data body.
The embedded area is an area for storing the metadata.
Program .

Images