Server, client, and content reproduction system

Abstract

To normally output on a client side a digital content acquired on a server side and protected by a hardware DRM.SOLUTION: A server transmits the digital content protected by the hardware DRM to a client and instructs the client to cancel the protection of the digital content by the hardware DRM, by a protection cancel unit owned by the client.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The disclosure herein relates to a server, a client, and a content playback system. [Background technology]

[0002] A cloud browser is known as one form of a browser (see, for example, Patent Document 1).

[0003] A cloud browser is a browser that runs on a server. The cloud browser generates the rendering results of a web page and sends them to the client. The client displays the rendering results that it receives.

[0004] Heavy-duty operations such as parsing web pages are performed on the cloud browser, so the client does not need to perform heavy-duty operations. The client can, for example, display rich web content even if its resources are poor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2022-77175 Summary of the Invention [Problem to be solved by the invention]

[0006] Digital content (such as videos) embedded in a web page may be protected by hardware DRM (Digital Rights Management). Digital content protected by hardware DRM can only be output to monitors and speakers directly connected to unprotected hardware devices. In other words, when digital content protected by hardware DRM embedded in a web page is played in a cloud browser, the digital content cannot be transmitted to the client. As a result, the user cannot view the digital content on the client.

[0007] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a server, a client, and a content playback system that can properly output, on the client side, digital content that is acquired on the server side and protected by hardware DRM. [Means for solving the problem]

[0008] A server according to one embodiment of the present invention is a server connected to a client, transmits digital content protected by hardware DRM to the client, and instructs the client to remove the hardware DRM protection applied to the digital content using a protection removal unit possessed by the client.

[0009] A client according to an embodiment of the present invention is a client connected to a server, and includes a protection removal unit and a player. The client receives digital content protected by hardware DRM from the server, removes the hardware DRM protection applied to the digital content in the protection removal unit in accordance with an instruction from the server, plays the digital content from which the hardware DRM protection has been removed in the player, and outputs the played content to an output device.

[0010] A content playback system according to an embodiment of the present invention is a system including a server and a client connected to the server. In the content playback system, the server transmits digital content protected by hardware DRM to the client and instructs the client to remove the hardware DRM protection applied to the digital content. In the content playback system, the client includes a protection removal unit and a player. The client receives the hardware DRM protected digital content from the server, removes the hardware DRM protection applied to the digital content using the protection removal unit in accordance with the instruction from the server, and plays the hardware DRM-free digital content using the player and outputs it to an output device. Effect of the Invention

[0011] According to one embodiment of the present invention, there is provided a server, a client and a content playback system that can properly output, on the client side, digital content protected by hardware DRM that has been acquired on the server side. [Brief description of the drawings]

[0012] [Figure 1] 1 is a block diagram showing a configuration of a content reproduction system according to an embodiment of the present invention. [Diagram 2] 1 is a diagram illustrating an outline of a process flow until a video distributed by a content distribution server is displayed on a display connected to a client in one embodiment of the present invention. [Diagram 3] 2 is a sequence diagram showing processes executed by each unit of the content reproduction system in one embodiment of the present invention. FIG. [Figure 4] FIG. 2 is a diagram illustrating an example of a functional configuration of a server and a client according to an embodiment of the present invention. [Diagram 5] FIG. 2 is a diagram illustrating an example of the hardware configuration of a server and a client according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] A content reproduction system according to an embodiment of the present invention, and a method and program executed by a computer included in the content reproduction system will be described in detail with reference to the drawings.

[0014] FIG. 1 is a block diagram showing a configuration of a content reproduction system 1 according to an embodiment of the present invention.

[0015] 1, the content reproduction system 1 includes a content distribution server 2, a server 10, a client 20, a display 30, and a speaker 40. The content distribution server 2, the server 10, and the client 20 are connected to each other via a network so as to be able to communicate with each other.

[0016] The display 30 and the speaker 40 may be an example of an output device 1006 described later. That is, the display 30 and the speaker 40 may be provided in the client 20.

[0017] The content distribution server 2 is, for example, a server that provides a video distribution service (VOD: Video On Demand), which is a type of cloud service. The number of content distribution servers 2 is not limited to one. There may be multiple content distribution servers 2.

[0018] In this embodiment, a technology for outputting digital content protected by hardware DRM obtained on the server side (cloud browser) on the client side will be explained using a video distribution service as an example, but this technology can also be applied to other fields (e.g., metaverse, mobility, VR (Virtual Reality), AR (Augmented Reality), etc.).

[0019] The server 10 includes a cloud browser 11, a Web application 12, and a control IF (Interface) 13.

[0020] The cloud browser 11 is a browser that runs on the server 10. The cloud browser 11 is a web browser that can interpret, for example, HyperText Markup Language (HTML), Cascading Style Sheets (CSS), JavaScript (registered trademark), and the like, and their related specifications.

[0021] For example, in response to a request from a client 20, the cloud browser 11 generates a request message conforming to the Hypertext Transfer Protocol (HTTP) and accesses a specified Uniform Resource Identifier (URI) to download Web content such as a Web page.

[0022] Cloud browser 11 interprets downloaded HTML format Web content and generates a DOM (Document Object Model) tree, a layout tree, etc. Cloud browser 11 sequentially renders each element of the Web content, whose layout has been determined, in an image buffer in server 10. The rendering result in the image buffer is transferred to client 20. By transferring the rendering result to client 20, the Web content is displayed on display 30.

[0023] In this way, high-load processing such as parsing of Web content is executed on the cloud browser 11. Therefore, the user can view rich Web content even if the performance of the cloud browser 11 is not high.

[0024] The Web application 12 is an application that runs on the cloud browser 11. The Web application 12 performs various procedures for video distribution between the content distribution server 2 and the Web application 12 in accordance with instructions from the cloud browser 11.

[0025] The control IF 13 is, for example, an API (Application Programming Interface), and connects the cloud browser 11 and an application 21 (described later) so that they can cooperate with each other. The control IF 13 includes an API for a media player (media player IF 13a) and an API for a CDM (Content Decryption Module) (CDM IF 13b).

[0026] The client 20 is a device that does not include a browser, and is connected to a display 30, which is an example of an output device, and a speaker 40. The client 20 is, for example, a set-top box, an HDMI (registered trademark) dongle, a thin client, an in-vehicle device, an electronic signboard, or the like.

[0027] The client 20 is not limited to a device that does not have a browser, but may be a device that has a browser, such as a smartphone, a tablet terminal, or a notebook PC.

[0028] The client 20 includes an application 21 , a CDM 22 and a media player 23 .

[0029] The application 21 performs various processes for implementing various functions of the present embodiment. For example, the application 21 accepts input according to a user operation related to a video (an example of digital content) distributed by the content distribution server 2. User operations related to a video include, for example, selecting, playing, stopping, fast-forwarding, and rewinding a video.

[0030] The CDM 22 is an example of a protection removal unit, and is a module for removing hardware DRM protection applied to digital content.

[0031] The media player 23 is an example of a player that plays back digital content. The media player 23 decodes and plays back digital content (for example, video data).

[0032] Here, hardware DRM is realized by providing a mechanism for managing the use of software and digital content in electronic components, and controlling the operation of the software that runs on the hardware with that mechanism. In other words, with hardware DRM, the copyright of the digital content is managed at the hardware layer, and usage is permitted under appropriate rights.

[0033] The hardware DRM protection is removed, and the deprotected digital content is played and output to an output device directly connected to the device. The digital content cannot be output to any device other than the output device directly connected to the device that removed the hardware DRM protection.

[0034] Typically, a media player and a CDM are built into a cloud browser. Therefore, the cloud browser removes the hardware DRM protection applied to digital content using the CDM built into the cloud browser, and plays the deprotected digital content using the media player built into the cloud browser. However, in this case, the digital content can only be output to an output device directly connected to the server on which the cloud browser is implemented. Therefore, a user cannot view the digital content on a client.

[0035] Therefore, in this embodiment, as shown in FIG. 1, the CDM 22 and the media player 23 are separated from the cloud browser 11 and arranged in the client 20.

[0036] FIG. 2 is a diagram showing an outline of the flow of processing until digital content (moving images) distributed by the content distribution server 2 is displayed on the display 30. As shown in FIG.

[0037] For example, when application 21 accepts a video playback operation by a user, it transmits a request to cloud browser 11. Cloud browser 11 renders a web page in response to this request and transmits the resulting image a to application 21, and also transmits video data A1 to application 21. This video data A1 is an example of digital content protected by hardware DRM.

[0038] That is, the server 10 (cloud browser 11) transmits digital content (video data A1) protected by hardware DRM to the client 20 (application 21).

[0039] The video data A1 is transferred from the server 10 to the client 20 by streaming, for example.

[0040] The cloud browser 11 instructs the application 21 to remove the hardware DRM protection applied to the video data A1. When the application 21 receives this instruction via the CDMIF 13b, which is an example of an API, it accesses the CDM 22 and removes the hardware DRM protection applied to the video data A1.

[0041] As a specific example, the CDM 22 is a dynamic library. When the cloud browser 11 instructs the application 21 to remove the hardware DRM protection applied to the video data A1, the cloud browser 11 instructs the application 21 to call the CDM 22 by dynamic linking. In response to this instruction, the application 21 removes the hardware DRM protection applied to the video data A1 by using the CDM 22.

[0042] That is, the server 10 (cloud browser 11) instructs the client 20 (application 21) via CDMIF13b (an example of a control interface) to remove the hardware DRM protection applied to the video data A1 (an example of digital content) using CDM22 (an example of a protection removal unit).

[0043] In addition, the client 20 (application 21) receives video data A1 (an example of digital content) protected by hardware DRM from the server 10 (cloud browser 11), and removes the hardware DRM protection applied to the video data A1 using CDM22 (an example of a protection removal unit) in accordance with instructions from the server 10 (cloud browser 11).

[0044] Here, when the cloud browser 11 transmits the image a to the application 21, it specifies an area in the web page where the video (image) is to be embedded according to the description in the HTML data. Hereinafter, when distinguishing between the image and the sound that compose the video, the former will be referred to as "video (image)" and the latter as "audio of the video."

[0045] The application 21 instructs the media player 23 to place a video (image) in that area (referred to as the "designated area"). In accordance with the instruction from the application 21, the media player 23 decodes the video data (referred to as "video data A2") from which hardware DRM protection has been removed, and aligns and draws the decoded video (image) in the designated area. For convenience, the decoded video (image) is referred to as "video A3 (image)".

[0046] The application 21 generates image B by combining image a with video A3 (image) aligned with the specified region, and outputs the image B to the display 30. As a result, image B (i.e., image a with video A3 embedded in the specified region) is displayed on the display 30, and the sound of the decoded video is output from the speaker 40 in synchronization with the video A3 (image).

[0047] In this manner, the application 21 plays back video (an example of digital content) from which hardware DRM protection has been removed on the media player 23 (an example of a player) and outputs it to the output device (the display 30 and the speaker 40).

[0048] A user can watch videos that are embedded in a web page and protected by hardware DRM on a display 30 and speakers 40 connected to a client 20 .

[0049] 3 is a sequence diagram showing the processes executed by each unit of the content playback system 1. Note that in this sequence diagram, various processes are shown concisely and clearly. As an example, a request is sent from the application 21 to the cloud browser 11 multiple times, but in this sequence diagram, for convenience, only one request is shown.

[0050] As shown in FIG. 3, when the application 21 receives a video playback operation by the user (step S101), the application 21 transmits a request to the cloud browser 11 (step S102).

[0051] The cloud browser 11 accesses the content distribution server 2 in response to a request from the application 21, and requests the video data A1 while performing various transactions such as license authentication. As a result, the video data A1 protected by hardware DRM is transferred (e.g., streamed) from the content distribution server 2 to the cloud browser 11.

[0052] The cloud browser 11 transfers the video data A1 transferred from the content distribution server 2 to the application 21 without removing the hardware DRM protection (step S103).

[0053] For example, it may take a long time to start up the media player 23 due to a performance problem of the client 20. Therefore, at this stage, the cloud browser 11 instructs the application 21 to start up the media player 23 (step S104). The application 21 that has received the instruction starts up the media player 23.

[0054] That is, the cloud browser 11 instructs the application 21 to start the media player 23 before instructing the application 21 to remove the hardware DRM protection applied to the video data A1. This allows the video to be played back on the media player 23 promptly after the hardware DRM protection is removed, even if it takes time to start the media player 23.

[0055] The cloud browser 11 renders the web page in response to a request from the application 21, and transmits the resulting image a to the application 21 (step S105).

[0056] The cloud browser 11 instructs the application 21 to remove the hardware DRM protection applied to the video data A1.

[0057] The application 21 calls the CDM 22, which is a dynamic library, and communicates (for example, key exchange and license authentication) with the cloud browser 11 in accordance with a procedure in accordance with the W3C (World Wide Web Consortium) standard. As a result, the application 21 uses the CDM 22 to remove the hardware DRM protection applied to the video data A1 (step S107).

[0058] The application 21 instructs the media player 23 to place the video A3 (image) in the designated area in the image a (step S108). The media player 23 decodes the video data A2 from which DRM protection has been removed, and aligns and draws the decoded video A3 (image) in the designated area.

[0059] The application 21 composites the video A3 (image) transferred from the media player 23 into a specified area in the image a received from the cloud browser 11 (step S110). The application 21 outputs the composite image B to the display 30, and outputs the audio of the decoded video to the speaker 40 in synchronization with the video A3 (image) (step S111).

[0060] Thus, according to this embodiment, even if the digital content acquired on the server side (cloud browser 11) is protected by hardware DRM, the user can view the digital content on the display 30 and speaker 40 connected to the client 20.

[0061] 4 is a diagram showing an example of the functional configuration of the server 10 and the client 20. As shown in FIG. 4, the server 10 and the client 20 include a control unit 110, a storage unit 120, a communication unit 130, an input unit 140, and an output unit 150.

[0062] Note that Fig. 4 shows only an example of the functional blocks of the server 10 and the client 20. The server 10 and the client 20 may include other functional blocks that are not shown in Fig. 4. Furthermore, the server 10 and the client 20 may not include some of the functional blocks.

[0063] The control unit 110 controls the server 10 and the client 20. The control unit 110 can be configured by a controller, a control circuit, or a control device that is explained based on common understanding in the technical field related to the present invention.

[0064] The storage unit 120 stores information used by the server 10 and the client 20. The storage unit 120 can be configured, for example, by a memory, a storage device, a storage device, or the like that is described based on a common understanding in the technical field related to the present invention.

[0065] The communication unit 130 performs communication between the server 10 and the client 20 (e.g., mutual communication between the two). The communication unit 130 can be configured with a transmitter / receiver, a transmission / reception circuit, or a transmission / reception device that is explained based on a common understanding in the technical field related to the present invention. The communication unit 130 may be configured with a transmission unit and a reception unit.

[0066] The input unit 140 accepts inputs from the server 10 and the client 20. The input unit 140 may also be connected to a predetermined device, storage medium, etc., and may accept input of data. The input unit 140 may output the input result to the control unit 110, for example.

[0067] The input unit 140 can be configured with input devices such as a keyboard, a mouse, and buttons, input / output terminals, input / output circuits, etc., which are explained based on common understanding in the technical field related to the present invention. The input unit 140 may also be configured to be integrated with a display unit (for example, a touch panel).

[0068] The output unit 150 performs output on the server 10 and the client 20. The output unit 150 may be configured to include a display unit that displays images, an audio output unit that outputs audio, and the like.

[0069] The display unit may be configured with a display device such as a display or monitor that is described based on a common understanding in the technical field of the present invention, and the audio output unit may be configured with an output device such as a speaker that is described based on a common understanding in the technical field of the present invention.

[0070] The block diagrams used in the description of the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of hardware and / or software. The means for realizing each functional block is not particularly limited. That is, each functional block may be realized by one physically combined device, or may be realized by two or more physically separated devices connected by wire or wirelessly.

[0071] For example, the devices (server 10 and client 20) according to an embodiment of the present invention may function as a computer that performs various processes according to an embodiment of the present invention.

[0072] 5 is a diagram showing an example of the hardware configuration of the server 10 and the client 20. The server 10 and the client 20 may be physically configured as computer devices including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

[0073] In this embodiment, the terms "apparatus," "circuit," "device," "unit," "server," etc. may be interchangeable. The hardware configurations of the server 10 and the client 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0074] For example, although only one processor 1001 is shown, there may be multiple processors, and the processes may be performed by a single processor or the processes may be performed by two or more processors simultaneously, serially, or otherwise. The processor 1001 may be implemented by one or more chips.

[0075] Each function of the server 10 and the client 20 is realized by loading a specific software (program) onto hardware such as a processor 1001 and a memory 1002, so that the processor 1001 performs calculations and controls communication via a communication device 1004, reading and / or writing of data in the memory 1002 and the storage 1003, etc.

[0076] The processor 1001 controls the entire computer by running, for example, an operating system. The processor 1001 may be configured with a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. Each unit such as the control unit 110 may be realized by the processor 1001.

[0077] The processor 1001 reads out programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes according to the programs. The programs used are those that cause a computer to execute at least a part of the operations described in the above embodiments. For example, the control unit 110 may be realized by a control program that runs on the processor 1001. Similarly, other functional blocks may be realized by control programs. The control programs are stored in the memory 1002, for example.

[0078] The memory 1002 is a computer-readable recording medium and may be composed of, for example, at least one of a Read Only Memory (ROM), an Erasable Programmable ROM (EPROM), an Electrically EPROM (EEPROM), a Random Access Memory (RAM), or other suitable storage medium.

[0079] The memory 1002 may be called a register, a cache, a main memory, etc. The memory 1002 may store executable programs (program codes), software modules, etc. for implementing a method according to an embodiment of the present invention.

[0080] Storage 1003 is a computer-readable recording medium. Storage 1003 may be, for example, at least one of a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disk (CD-ROM (Compact Disc ROM)), a digital versatile disk, a Blu-ray (registered trademark) disk), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic stripe, a database, a server, and other suitable storage media.

[0081] The storage 1003 may be called an auxiliary storage device. The storage unit 120 may be realized by the memory 1002 and / or the storage 1003.

[0082] The communication device 1004 is hardware (transmission / reception device) for performing communication between computers via at least one of a wired network and a wireless network. The communication device 1004 is also called, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may include a SIM card. Note that the communication unit 130 may be realized by the communication device 1004.

[0083] The input device 1005 is an input device (e.g., a keyboard, a mouse, etc.) that accepts an input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may be integrated into one (e.g., a touch panel). The input unit 140 and the output unit 150 may be realized by the input device 1005 and the output device 1006, respectively.

[0084] Each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured by a single bus, or may be configured by different buses between the devices.

[0085] Furthermore, the server 10 and the client 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA), etc., and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented by at least one of these pieces of hardware.

[0086] (Modification) In addition, terms explained in this disclosure and / or terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings.

[0087] The information, parameters, etc. described in this disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. Furthermore, the names used for parameters, etc. in this disclosure are not limiting in any respect.

[0088] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0089] Information, signals, etc. may be input and output via multiple network nodes. Input and output information, signals, etc. may be stored in a specific location (e.g., memory) or may be managed using a table. Input and output information, signals, etc. may be overwritten, updated, or appended. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0090] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0091] Also, software, instructions, information, etc. may be transmitted and received via a transmission medium and / or signal waveform. For example, if the software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)) and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of a transmission medium.

[0092] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched according to implementation. In addition, the processing procedures, sequences, flow charts, etc. of each aspect / embodiment described in this disclosure may be reordered unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0093] In addition, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made in the implementation stage without departing from the gist of the invention. In addition, the functions executed in the above-mentioned embodiment may be implemented in appropriate combinations as much as possible. The above-mentioned embodiment includes various steps, and various inventions can be extracted by appropriate combinations of the multiple components disclosed. For example, if an effect can be obtained even if some components are deleted from all the components shown in the embodiment, the configuration from which the components are deleted can be extracted as an invention. [Explanation of symbols]

[0094] 1: Content playback system 2: Content distribution server 10: Server 11: Cloud Browser 12: Web Applications 13: Control IF 20: Client 21: Application 22: CDM 23: Media Player 30: Display 40: Speaker 110: Control unit 120: Storage section 130: Communications Department 140: Input section 150: Output section 1001: Processor 1002: Memory 1003: Storage 1004 :Communication equipment 1005: Input device 1006 : Output device 1007: Bus

Claims

1. A server connected to a client, Transmitting digital content protected by hardware DRM (Digital Rights Management) to the client; instructing the client to remove the hardware DRM protection applied to the digital content using a protection removal unit included in the client; server.

2. instructing the client to start a player for playing the digital content before instructing the client to remove the hardware DRM protection applied to the digital content; The server of claim 1 .

3. the protection removal unit is a dynamic library, instructing the client to call the dynamic library by dynamic linking when instructing the client to remove the hardware DRM protection applied to the digital content; The server of claim 1 .

4. A client connected to a server, A protection release unit; a player; receiving hardware DRM protected digital content from the server; The protection removal unit removes the hardware DRM protection applied to the digital content in accordance with an instruction from the server; The digital content from which the hardware DRM protection has been removed is played on the player and output to an output device. client.

5. an application that receives an input corresponding to a user operation related to the digital content; The application may include receiving an instruction from the server, the protection removal unit removes the hardware DRM protection applied to the digital content; The client of claim 4.

6. The protection removal unit is a Content Decryption Module (CDM). A client according to claim 4 or claim 5.

7. A content playback system including a server and a client connected to the server, The server, Transmitting hardware DRM protected digital content to said client; Instructing the client to remove the hardware DRM protection applied to the digital content; The client: A protection release unit; a player; receiving hardware DRM protected digital content from the server; The protection removal unit removes the hardware DRM protection applied to the digital content in accordance with an instruction from the server; The digital content from which the hardware DRM protection has been removed is played on the player and output to an output device. Content playback system.

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