KR101479582B1 - Device and method performing source/sink role switch in wifi display communication - Google Patents

Abstract

According to another aspect of the present invention, there is provided a mobile terminal including a search unit for searching for another device capable of WFD (WiFi Display) communication, a role relation setting unit for setting a sink / source role relationship with another selected one of the other devices, And a communication unit for receiving data from the other device and transmitting data to the other device when the selected other device is set as a sink device, the device for performing the source / sink role conversion in the WFD communication and the source / A role switching method is disclosed.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a device and a method for performing a source / sink role conversion in a WFD communication,

Embodiments relate to a WFD connection between a source device and a sink device, and more particularly to a sink device and a sink system for deriving a WFD connection.

Background Art [0002] With the recent development of electronic communication technology, technologies using wireless communication technology have been widely used in all industrial fields including a communication field as well as a service field. Accordingly, various services such as voice call, data transmission, and the Internet are provided based on a wireless network. Typical wireless communication technologies based on the wireless communication network include WiBro (Wireless Broadband Internet) And WiFi (Wireless Fidelity).

Wi-Fi is a wireless local area network (WLAN) technology that enables high-performance wireless communication by combining wireless technology with Hi-Fi (High-Fidelity) as one of short-range wireless communication technologies using IEEE 802.11 as a standard. Wireless LAN technology is a method of constructing a network by using radio waves or light, instead of using a wired network.

With this Wi-Fi technology, portable computers such as notebook computers can be connected wirelessly. In addition, Wi-Fi technology allows multiple PCs to be connected and transfer large file, graphics, video and audio information. In recent years, data communication using Wi-Fi has become possible in portable computers such as notebook computers, smart pads, and smart phones.

WFD (WiFi Display; Miracast) technology is a screen sharing method using Wi-Fi, and is related to screen sharing for displaying display information provided by a source device in a sink device.

The screen sharing method using the conventional WFD technology is inconvenient to set a WFD connection for a sink device in the source device and add it to a connection group in the case where one source device exists and one or more sink devices exist exist.

1 is a flowchart of a step in which a sink device and a source device exchange messages for a WFD connection according to a conventional WFD technology scheme. Referring to FIG. 1, there is a message exchange between devices performing different kinds of roles. One of the devices performing a different kind of role is the source device and the other is the sink device. The source device captures and encodes its own screen and sound, and then transmits the packet to the sink device through the wireless network. The sink device decodes the contents of the received packet and outputs it to the display of the sink device. Such screen output is referred to as mirroring, and through mirroring, the user can see and hear the screen and sound of the source device on the sink device.

Referring to FIG. 1, a source device or a sink device may be found in the WFD service discovery step. That is, the source device may discover the sink device or the sink device may discover the source device. To establish a WFD connection, a P2P network can be connected using technologies such as WiFi Direct or Tunneled Direct Link Setup (TDLS). The Wi-Fi direct and tunnel direct link setting are network communication technologies that enable data sharing without requiring a separate intermediary for the network between the two devices.

In FIG. 1, in a function exchange and negotiation step, a source device and a sink device determine a WFD capability that can be provided to each other using a real-time streaming protocol (RTSP) format message, and a real WFD connection . RTSP method is a protocol for controlling the delivery of real-time data such as audio and video contents. The RTSP method (RTSP method) is a method for describing a media object between two devices in RTSP, setup, play, encoding, set-parameter, pause, and tear-down operations. For example, both devices must have an RTSP method for play to play the media entity.

FIG. 2 is a flow chart for explaining the function exchange and negotiation steps in the WFD connection according to the conventional method. In the above-described function exchange and negotiation step, the source device transmits a message requesting a list of RTSP methods supported by the sink device (S11). That is, by checking the list of RTSP methods that the sink device can support, it can be confirmed whether or not the function for media playback is provided. The sink device transmits a list of RTSP methods provided by the sink device to the source device (S12).

Then, the sink device transmits a message requesting the RTSP method list (S21). The source device transmits a list of RTSP methods provided by the source device (S22). Accordingly, the two devices can acquire mutually available RTSP methods.

Thereafter, the source device transmits a message (get_parameter request) including an intention to make a WFD connection (S31). The sink device transmits a message including a WFD capability (W32) supported by the sink device (S32). The source device determines a function to be used among the WFD functions provided by the sink device and transmits a message (S41). The sink device accepts the function determined by the source device, and transmits a message including an acceptance intention (S42). The sink device may then receive the AV stream delivered from the source device.

3 is a simplified block diagram of the WFD connection process of FIG. Referring to FIG. 3, a WFD connection is requested at a source device (S1), a sink device accepts it (S2), a WFD connection is established at a negotiation phase (S3), a WFD connection (S4) can be found. However, there is no inconvenience in the situation of one source device and one sink device when operating as shown in FIG. 3, but there is a problem in controlling the WFD connection when there is one source device and a plurality of sink devices.

For example, when there are one source device and N sink devices, one source device must make a connection to all N sink devices, so that the user of the source device must input an input for N times WFD connections, which is cumbersome . In addition, when a new sink device is added while mirroring the screen and sound of one source device to the N sink devices, a screen for setting a new WFD connection is also shared with other sink devices.

In order to solve the above problems, according to one aspect of the present invention, an apparatus, a method, and a system are required in which a sink device indirectly controls a source device so that the source device makes a request for a WFD connection.

A device for performing a source / sink role conversion in WFD communication according to an exemplary embodiment of the present invention includes a search unit for searching for another device capable of WFD (WiFi Display) communication, a sink / A role relation setting unit for setting a source role relationship and a communication unit for receiving data from the other device when the selected other device is set as a source device and transmitting data to the other device when the selected other device is set as a sink device .

In addition, in the device, the role relationship setting unit may include an RTSP list setting unit that receives a list of RTSP methods that the other device can support from the other device and provides the other device with a list of RTSP methods that the device can support, And a source / sink role switching unit for transmitting a role switching parameter message for switching the source / sink role to another device.

In addition, in the device, the source / sink role switching unit may check whether the other device can perform a source / sink role change, and if the other device can perform a source / sink role change, And transmits the message.

In addition, in the device, the role relation establishing unit may transmit a message requesting switching of the source / sink role to the other device, and based on a response to the message requesting the source / sink role change, / ≪ / RTI > sink role switching can be performed.

In addition, in the device, the source / sink role switching unit may set the other device as a source device and the device as a sink device by transmitting the role switching parameter message.

In addition, in the device, the role relationship setting unit may receive a first RTSP setup parameter request message from the other device, and transmit a second RTSP setup parameter request message to the other device in response to the received RTSP setup parameter message To the mobile station.

In the device, the data may be data related to a streaming image.

Also, in the device, the source / sink role switching unit may check whether the other device can perform the source / sink role change, and if the other device can not perform the source / sink role change, Sink device, and sets the device as a source device.

In the device, the data may be data related to a streaming image.

A source / sink role switching method in WFD communication according to an embodiment of the present invention includes a searching step of searching for another device capable of WFD (WiFi Display) communication, a sink / source role relationship And a communication step of receiving data from the other device when the selected other device is set as a source device and transmitting data to the other device when the selected other device is set as a sink device .

In the method, the role relationship setting step may include: an RTSP list setting step of receiving a list of RTSP methods that the other device can support from the other device and providing a list of RTSP methods that the device can support to the other devices; And a source / sink role switching step of transmitting a role switching parameter message for switching the source / sink role to the other device.

In the above method, the step of switching the source / sink role includes checking whether the other device can perform the source / sink role change, and if the other device can perform the source / sink role change, To the mobile station.

In the above method, the step of establishing the role relationship may include: transmitting a message requesting switching of the source / sink role to the other device; and transmitting the source / And confirming whether or not the sink role conversion can be performed.

In the method, the source / sink role switching step may set the other device as a source device and the device as a sink device by transmitting the role switching parameter message.

In the method, the role relationship setting step may include receiving a first RTSP setup parameter request message from the other device, and, in response to the received RTSP setup parameter message, transmitting a second RTSP setup parameter request message to the other device And transmits the data.

In the above method, the data may be data relating to a streaming image.

In the above method, the switching of the source / sink role may include checking whether the other device can perform source / sink role switching, and if the other device can not perform source / sink role switching, And setting the device as a source device.

In the above method, the data may be data relating to a streaming image.

According to an aspect of the present invention, a sink device requests a connection without a separate input of a user of a source device and is added to a WFD connection group so that a screen can be automatically shared, thereby eliminating the inconvenience of the existing method and improving convenience .

1 is a flowchart of a step in which a sink device and a source device exchange messages for a WFD connection according to a conventional WFD technology scheme.
2 is a flow chart illustrating the function exchange and negotiation steps in a conventional WFD connection.
3 is a simplified block diagram of the WFD connection process of FIG.
4 is a configuration diagram of a sink system according to an embodiment of the present invention.
5 is a configuration diagram for providing a user selection for a source mode and a sink mode in a WFD connection with another device in another embodiment of the present invention.
6 is a flow diagram of the functional exchange and negotiation steps according to one embodiment of the present invention.
7 is a block diagram of a sync system according to another embodiment of the present invention.
8 is a flowchart of a sync request method according to an embodiment of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises ", or" having ", or the like, specify that there is a stated feature, number, step, operation, , Steps, operations, components, parts, or combinations thereof, as a matter of principle.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be construed as meaning consistent with meaning in the context of the relevant art and are not to be construed as ideal or overly formal in meaning unless expressly defined herein . Like reference numerals in the drawings denote like elements.

In the following description, well-known functions or constructions are not described in detail to avoid unnecessarily obscuring the subject matter of the present invention. In addition, the size of each component in the drawings may be exaggerated for the sake of explanation and does not mean a size actually applied.

Embodiments described herein may be wholly hardware, partially hardware, partially software, or entirely software. A "unit," "module," "device," or "system" or the like in this specification refers to a computer-related entity such as a hardware, a combination of hardware and software, or software. A processor, an object, an executable, a thread of execution, a program, and / or a computer, for example, a computer, but is not limited to, a computer. For example, both an application running on a computer and a computer may correspond to a part, module, device or system of the present specification.

Embodiments have been described with reference to the flowcharts shown in the drawings. While the above method has been shown and described as a series of blocks for purposes of simplicity, it is to be understood that the invention is not limited to the order of the blocks, and that some blocks may be present in different orders and in different orders from that shown and described herein And various other branches, flow paths, and sequences of blocks that achieve the same or similar results may be implemented. Also, not all illustrated blocks may be required for implementation of the methods described herein. Further, the method according to an embodiment of the present invention may be implemented in the form of a computer program for performing a series of processes, and the computer program may be recorded in a computer-readable recording medium.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In the present invention, the use of the terms sink and source in the sink device and the source device is the result of one embodiment of the present invention. That is, a device for receiving and displaying display information is represented as a sink device.

4 is a configuration diagram of a sink system according to an embodiment of the present invention. The sink system 10 may include a sink device 100 and a source device 200. In addition, a plurality of sink devices 100 may exist in the sink system 10. [ In this specification, the sink device 100 may be referred to as a device performing a source / sink role conversion in WFD communication, and the source device 200 may be referred to as another device.

4, the device 100 for performing the source / sink role conversion may include a search unit 110, a role relationship setting unit 120, and a communication unit 130. [

The search unit 110 can search for another device capable of WFD (WiFi Display) communication. The role relation setting unit 120 can set a sink / source role relationship with other selected devices among the searched devices. The communication unit 130 may receive data from the other device when the selected other device is set as a source device, and may transmit data to the other device when the selected other device is set as a sink device.

Referring to FIG. 4, the role relationship setting unit 120 may include an RTSP list setting unit 121 and a source / sink role switching unit 122.

Each of the sink device 100 and the source device 200 may be connected to the internet such as a smart phone, a tablet PC, a notebook, a personal digital assistant (PDA), a digital camera, a desktop, And various application programs can be executed based on an operating system (OS).

The OS is a system program for allowing an application program to use the hardware of a computer and includes all operating systems that can be installed in mobile computers such as Android OS, iOS, Windows Mobile OS, Sea OS, Symbian OS, Blackberry OS .

The application program is a program developed to perform a specific task using a computer. The application program includes not only various applications but also various multimedia contents such as a game, a moving image, a photograph, etc., an image viewer for executing the multimedia contents, Of the execution program of the program.

The sink device 100 may display the streaming image information provided from the source device 200. [ The system 10 includes a platform for supporting wireless LAN communication, and the sink device 100 and the source device 200 communicate with each other via a wireless LAN. The wireless LAN may be a wireless local area network (WLAN) such as WiFi (Wireless Fidelity) and TDLS (Tunneled Direct Link Setup) in a manner that enables high-speed Internet access within a certain distance using radio waves or infrared rays without using wires. You can include both.

According to an embodiment of the present invention, the sink device 100 may perform a process of discovery of the source device 200 on the wireless LAN system. After the sink device 100 discovers an arbitrary source device 200 and a P2P network is connected between the sink device 100 and the source device 200, a step of performing a Capability Exchange and Negotiation You can enter.

Hereinafter, functions and configurations of the sink device 100 in the function exchange and negotiation steps will be described.

The RTSP list setting unit 121 of the sink device 100 may transmit a message requesting a real-time streaming protocol (RTSP) method list to another device 200. [ Here, the message may mean a packet including specific data. The RTSP method list requested by the RTSP list setting unit 121 is a list of RTSP methods supported by the source device 200.

In response to the request, the sink device 100 may receive a message from the source device 200 including a list of RTSP methods supported by the source device 200.

Sink device 100 may receive a message from source device 200 requesting a list of RTSP methods. The RTSP method list requested by the sink device 100 is a list of RTSP methods supported by the sink device 100.

The sink device 100 may transmit a message including a list of RTSP methods supported by the sink device 100 to the source device 200. [

Through the above process, the sink device 100 can check the list of RSTP methods available in the WFD connection with the source device 200.

As described above, at the beginning of the function exchange and negotiation step of the WFD connection according to an embodiment of the present invention, the sink device 100 can serve as a source device of a general WFD connection. Then, the sink device 100 functions as a general sink device by performing a specific function (role exchange between the source device and the sink device).

The source / sink role switching unit 122 may transmit a role switching parameter message (e.g., a GetParameter extened parameter) for causing the source device 200 to perform the source / sink role switching. The role change parameter message may be a command instructing the sink device to request a WFD connection. That is, the sink device 100 does not directly request the WFD connection to the source device 200, but rather directs the source device 200 to request the sink device 100 to make a WFD connection.

In one embodiment, the source / sink role switching unit 122 determines whether the source device 200 can perform a source / sink role transition and if the source device 200 performs a source / sink role transition If yes, the Role Switching parameter message may be transmitted.

Herein, the role change parameter message includes a message asking the sink device 100 whether the WFD connection request is possible, and a message instructing the sink device 100 to request the WFD connection to the sink device 100 Message. ≪ / RTI >

Specifically, in response to the inquiring message, the source apparatus 200 may determine whether a request for a WFD connection is possible and transmit a message that a WFD connection request is possible. In response, the sink device 100 may send a message instructing the source device 200 to make a WFD connection request. Then, the source apparatus 200 may transmit a message to the sink apparatus 100 to perform the WFD connection request.

That is, the role relation establishing unit 120 receives the first RTSP setup parameter request message from the source apparatus 200, and transmits the second RTSP setup message to the source apparatus 200 in response to the received RTSP setup parameter message. Parameter request message. The first and second RTSP configuration parameter request messages are mutually confirmed information for establishing an RTSP between the two devices.

The sink device 100 asks if the source device 200 can perform the source / sink role transition, and if the source device 200 responds with a message that the source / sink role transition is possible, Sink device 100 is capable of sending a message (a message to perform source / sink role exchange) instructing source device 200 to attempt a WFD connection request.

Specifically, the source / sink switching switcher 122 sets the source device 200 as a source device for transmitting streaming video data by transmitting the role switching parameter message, and transmits the sink device 100 to the streaming It can be set as a sink device for receiving video data.

Accordingly, the role relationship establishing unit 120 can receive the WFD connection request from the source apparatus 200. [ Specifically, the sink device 100 may receive a message including an intention to make a WFD connection. The WFD connection request of the source device 200 can be performed after the source device 200 determines that the sink device 100 is suitable for WFD connection with the source device 200 based on the role change parameter message have.

The sink device 100 may receive a WFD connection request from the source device 200 and then send a message containing a WFD capability list to the source device 200 in response to acknowledging the connection request . Here, the WFD function list includes a capability related to the streaming image information that the sink device 100 can use in the WFD connection. After the source / sink role switching step, the WFD connection processing unit (not shown) can process the information about the WFD connection.

Then, the source apparatus 200 selects a WFD function to be used from the WFD function list provided by the sink apparatus 100, and transmits the message to the sink apparatus 100. In response, the sink device 100 may send a message to the source device 200 that has an acceptance implication for the WFD function selected by the source device 200.

The sink device 100 may be WFD-connected to receive data from the source device 200, and the data may be data for a streaming image. Accordingly, the sink device 100 can display the image of the source device 200 through the display unit.

In another embodiment, the source / sink role switching section 122 determines whether the source device can perform the source / sink role transition, and if the source device can not perform the source / sink role transition, As a sink device for receiving and displaying data, and setting the sink device as a source device for providing data to the sink device. That is, depending on the function of the other device, the device 100 can selectively operate as one of the source device and the sink device. In this case, since the other device can not use the source / sink role switching function, the device 100 that requested the RTSP method list first operates as the source device. Accordingly, the device 100 may transmit data to the other device 200, and this data may be related to a streaming image.

5 is a configuration diagram for providing a user selection for a WFD connection in a source mode and a sink mode in a WFD connection with another device in another embodiment of the present invention;

Referring to FIG. 5, a user may select a source mode 510 or a sink mode 520 of a device used by the user. If the source mode 510 is selected, the screen of the user can be displayed on the screen of the other device. If the user selects the sink mode 520, the screen of the other device can be displayed on the screen of the user.

In particular, at least one of the other devices capable of WFD communication around the user device 1000 may be selected based on user input, and the source / sink role switching function may be performed based on the user input.

5, when the source mode 520 is selected, the user device 1000 does not transmit a role change parameter message, and transmits an RTSP setup message in which the user device 100 directly requests a WFD connection to another device. In this case, the user device 1000 requesting the list of RTSP methods according to a typical WFD step performs a role as a general source device. The conversion between these modes may be performed by the role relationship setting unit 120 based on the user's selection, and the user input may include any means such as a touch to the touch screen. By allowing the user to select the operation as the source and the sink as described above, the streaming video exchange between the two devices can be tailored to the user convenience.

In yet another embodiment, the device 100 according to the present invention may further include an automatic execution unit (not shown) for executing the role relationship setting unit 120. [ When the sink device 100 and the source device 200 are positioned within a predetermined distance, the automatic execution unit 160 can execute and control the role relationship setting unit 110. [

Specifically, when the sink device 100 is located in a place where the source device 200 can communicate with the source device 200, the automatic execution module 160 can execute the role relationship setting module 120 for the WFD connection with the source device 200 have. Accordingly, the role relation setting unit 120 can select another device with the strongest signal strength or user input.

In another embodiment, the auto-run unit may provide a message pop-up window 500 for selecting a source / sink mode, as shown in FIG.

Hereinafter, functions and configurations of the source apparatus 200 in the function exchange and negotiation steps will be described. In describing the function and configuration of the source apparatus 200, the description of the functions and configurations of the sink apparatus 100 described above can be referred to.

In response to a request from the sink device 100, the source device 200 may send a message containing a list of RTSP methods to the sink device 100. Thereafter, the source apparatus 200 may receive the role change parameter message from the sink apparatus 100. [ The role change parameter message includes a message instructing the sink device 100 to request a WFD connection.

In another embodiment, the source device 200 may receive an RTSP configuration parameter request message in addition to the role switch parameter message. The source apparatus 200 can determine whether a WFD connection with the sink apparatus 100 is possible based on the role change parameter message. Specifically, the source device 200 can determine whether the source device 200 can support source / sink exchange capability and whether it can perform a WFD connection request to the sink device 100 have.

The source device 200 may attempt to request a WFD connection to the sink device 100 when the source / sink role exchange function is supported.

6 is a flow diagram of the functional exchange and negotiation steps according to one embodiment of the present invention. Referring to FIG. 6, the sink device 100 may transmit a message requesting a list of RTSP methods to the source device 200 (S61). Then, the source device 200 can sequentially transmit a message requesting a list of RTSP methods supported by the source device and a list of RTSP methods supported by the sink device (S62).

In response, the sink device 100 may send a message to the source device 100, including a list of RTSP methods supported by the sink device 100.

Thereafter, the source apparatus 200 can determine whether or not it has received the role change parameter message (S63). Upon receiving the role change parameter message, the source device 200 may determine whether it can support source / sink role switching and may request a WFD connection to the sink device 100 if the source device 200 can support it.

However, if the source device 200 fails to receive the role change parameter message, the source device 200 can wait and receive a WFD connection request from the sink device 100 (S65). The source device 100 receiving the role change parameter message can determine whether a WFD connection request to the sink device 100 is possible based on the role change parameter message. When it is determined that the WFD connection request is possible, the source apparatus 200 can request the WFD connection to the sink apparatus 100. In response to this, the sink device 100 transmits a message including an intention of acceptance so that the source device 100 performs a role as a source device in the WFD connection, so that the sink device can display the screen of the source device, Can be provided.

In another embodiment, the source device 200 may include a cryptographic function to limit the WFD connection to the sink device 100. The source device 220 may execute the encryption step after receiving the role switch parameter message or may perform the encryption step after being discovery by the sink device 100. [

When the source apparatus 200 is WFD-connected to the sink apparatus 100, the source apparatus 200 can provide streaming image information of the source apparatus 200 to the sink apparatus 100 through image preparation (not shown). Accordingly, the sink device 100 can display the screen of the source device 200 on the sink device 100. [

The functions and configurations of the sink system 10 for the function exchange and negotiation steps in one embodiment of the present invention are described with reference to the descriptions of the functions and configurations of the sink device 100 and the source device 200 described above Lt; / RTI >

Referring to FIG. 4, a sink system 10 including a source device 200 connected to a wireless network and one or more sink devices 100 is shown.

In the system 10 of FIG. 4, the source device 200 can perform the functions described above and is also referred to as another device. The sink device 100 can also perform the functions as described above, and is referred to as a user device or a device that performs source / sink role switching.

In the sink system 10, the source device 200 provides a streaming image to the sink device 100, and the sink device 100 can display a streaming image provided by the source device. The image may be a moving image including a voice. Although a wireless access device (AP) 1000 is illustrated in FIG. 4, it may be omitted.

7 is a block diagram of a sync system according to another embodiment of the present invention. Referring to FIG. 7, a sink device 702 for WFD connection with one source device 701 for displaying a streaming image and a sink device 703 for transmitting request information for additional WFD connection appear.

Specifically, in the sink system 10, the source apparatus 200 can receive a role switching parameter message in a WFD-connected state with another sink apparatus. That is, while one source device 200 is providing a streaming image to another sink device, the source device 200 may add a WFD connection to the new sink device based on the role switch parameter message.

8 is a flowchart of a sync request method according to an embodiment of the present invention. Specifically, FIG. 8 shows the flow of message exchange between two devices in the function exchange and negotiation phase. In FIG. 8, device 1 and device 2 may be in a wireless network connection, device 2 may be viewed as sink device 100, and device 1 may be viewed as source device 200.

8, the device 2 operates as a source device (S11, S12, S21, S22), and a step of a P region (a step in a square box indicated by a dotted line; S311, S312, S411, and S412) Thereafter, from the steps S31, S32, S41, and S42, the device 2 then operates as a sink device. If the step of the P region is not performed, the device 2 can function as a source device in a general WFD connection.

Referring to FIG. 8, the device 2 transmits a message requesting a list of RTSP methods supported by the device 1 (S11). Then, the device 1 transmits a message including a list of RTSP methods provided by the device 1 to the device 2 (S12). Thereafter, the device 1 transmits a message requesting a list of RTSP methods supported by the device 2 (S21). The device 2 transmits a list of RTSP methods supported by the device 2 (S22).

The device 2 transmits a role change parameter message (e.g., RTSP GET_PARAMETER) to the device 1 (S311). This message may include a message asking if Device 1 can perform a source / sink role transition (i.e., Device 1 can make a WFD connection request). In response, the device 1 transmits a message including a capability field to the device 2 (S312). Source / sink role switching means a function that can operate as a source device and a sink device.

In step S312, the device 2 checks whether the device 1 supports switching of the source / sink role of the device 1 in the received message, and if the device 1 is confirmed to support the source / sink role conversion, To the device 1 (S411). Here, a message including an intention to use the source / sink role switching may include a message indicating that the device 1 requests the device 2 to make a WFD connection.

After step S411, the device 1 sends a message to the device 2 that includes an intention to perform the source / sink role transition in response to the step S411. Accordingly, the apparatus 1 serves as a general source apparatus, and the apparatus 2 can perform a role of a sink apparatus. Accordingly, the device 1 transmits, as a source device, a message including an intention to WFD connection to the device 2 (S31). In response, the device 2 transmits a message including the WFD function supported by the device 2 to the device 1 (S32). The device 1 determines a function to be used among the WFD functions provided by the device 2 and transmits a message to the device 2 (S41). The function may be information on a streaming image. The device 2 may accept the request of the device 1 and establish a WFD connection with the device 1 as a sink (S42). In addition to the above, it should be acknowledged that there may be other exchange of information between Device 1 and Device 2.

The subsequent steps may be the same as the order of message exchange between the source device and the sink device in a typical WFD connection.

While the invention has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. However, it should be understood that such modifications are within the technical scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (18)

A search unit for searching for another device capable of WFD (WiFi Display) communication;
Determining whether another selected device among the searched devices can perform a source / sink role change, setting a sink / source role relationship with the selected other device according to a result of the check, A role relationship setting unit for transmitting a role switching parameter message to the selected other device if the switching can be performed; And
And a communication unit for receiving data from the selected other device when the selected other device is set as a source device and transmitting data to the selected other device when the selected other device is set as a sink device, The device that performs the conversion.
The method according to claim 1,
Wherein the role-
An RTSP list setting unit that receives a list of RTSP methods that can be supported by the selected other device from the selected other device and provides a list of RTSP methods that the device itself can support to the selected other device; And
And a source / sink role switching unit for transmitting a role switching parameter message for performing a source / sink role switching to the selected other device in the source / sink role switching in the WFD communication.
delete The method according to claim 1,
Wherein the role-
Transmitting a message requesting switching of the source / sink role to the selected other device,
And determines whether the selected other device can perform a source / sink role change based on a response to the message requesting the source / sink role change.
The method according to claim 1,
Wherein the role-
And setting the selected other device as a source device and setting the device itself as a sink device by transmitting the role switching parameter message.
6. The method of claim 5,
Wherein the role-
Receiving a first RTSP setup parameter request message from the selected other device,
And transmits a second RTSP setup parameter request message to the selected other device in response to the received RTSP setup parameter request message.
delete The method according to claim 1,
Wherein the role-
Confirms whether the selected other device can perform a source / sink role change,
And setting the selected other device as a sink device and setting the device itself as a source device if the selected other device can not perform the source / sink role change. device.
The method according to claim 1,
Wherein the data is data relating to a streaming image.
A searching step of searching for another device capable of WFD (WiFi Display) communication;
Determining whether another selected device among the searched devices can perform a source / sink role change, setting a sink / source role relationship with the selected other device according to a result of the check, A role relationship setting step of transmitting a role switching parameter message to the selected other device if the switching can be performed; And
And a communication step of receiving data from the selected other device when the selected other device is set as a source device and transmitting data to the selected other device when the selected other device is set as a sink device, How to convert roles.
11. The method of claim 10,
Wherein the role-
An RTSP list setting step of receiving a list of RTSP methods that the selected other device can support from the selected other device and providing a list of RTSP methods that the device itself can support to the selected other device; And
And a source / sink role switching step of transmitting a role switching parameter message for performing a source / sink role switching to the selected other device.
delete 11. The method of claim 10,
Wherein the role-
Transmitting a message requesting switching of the source / sink role to the selected other device,
And determines whether the selected other device can perform a source / sink role change based on a response to the message requesting the source / sink role change.
11. The method of claim 10,
Wherein the role-
And setting the other device as a source device and setting the device itself as a sink device by transmitting the role switching parameter message.
15. The method of claim 14,
Wherein the role-
Receiving a first RTSP setup parameter request message from the selected other device,
And transmitting a second RTSP setup parameter request message to the selected other device in response to the received RTSP setup parameter request message.
delete 11. The method of claim 10,
Wherein the role-
Confirms whether the selected other device can perform a source / sink role change,
And setting the selected other device as a sink device and setting the device itself as a source device if the selected other device can not perform the source / sink role change.
11. The method of claim 10,
Wherein the data is data relating to a streaming image.

Images