KR100655554B1 - Universal multimedia access system - Google Patents

Abstract

The present invention relates to a UMA system that enables universal multimedia access by performing adaptive conversion of a corresponding multimedia according to a specification of a receiving terminal when transmitting multimedia in an IMS environment.

The present invention provides a database including spec information of a user terminal device; An application server connected to a database to obtain a specification of a receiving user terminal device and to perform adaptive transcoding of a receiving terminal device of a multimedia resource; Addressing manager for addressing the data transmitted from the user terminal device via the application server. The present invention provides a method for realizing a transcoding service that optimally adjusts a frame rate or resolution of a multimedia resource in accordance with specifications of various terminal devices.

IMS, Universal Multimedia Access (UMS)

Description

Universal multimedia access system {UNIVERSAL MULTIMEDIA ACCESS SYSTEM}

1 is a schematic configuration diagram of an IP multimedia subsystem (IMS)

2 is a diagram showing the configuration of an IMS system according to a first embodiment of the present invention;

3 is a diagram showing the configuration of an IMS system according to a second embodiment of the present invention;

4 is a flowchart showing a multimedia access control procedure of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: transcoding application server 200: HSS

300: CSCF 400: mobile network

500: user terminal 600: MGCF

700: MGW 800: PSTN

110: specification information management and transcoding module 210: specification information database

310: addressing module

The present invention relates to a user terminal device adaptive universal multimedia access (UMA) system for multimedia resources in an Internet Protocol Multimedia Subsystem (IMS) environment.

In particular, the present invention relates to a system structure and method for realizing universal multimedia access for providing an optimal multimedia service adaptive to a terminal environment in an IMS environment.

As IP-based multimedia services are actively performed in WLAN-based notebook and PDA environments, attempts to combine mobile communication and IP-based environments have been made in various aspects. The most specific of these is the IMS, which is being carried out by the 3rd Generaion Partnership Project (3GPP), the 3rd generation mobile communication standard in Europe. Presenting.

Among the various services expected by using the IMS, video services and games such as video communication, video chat, and video conferencing are mainly talked about as main applications, and all include video or graphic services using a display of a terminal device as well as voice. Doing.

First, an overview of the IMS environment.

Standard activities for supporting a variety of services by connecting an IP network capable of providing abundant services using a wireless mobile communication terminal device are being actively performed based on the 3rd generation Generaion Partnership Project (3GPP), a European 3rd generation mobile communication standard. This is called IMS, and this standard mainly defines which server can be connected between different terminals. That is, it defines which components are needed and which sequence can connect IP network.

1 schematically shows an IMS system. Referring to FIG. 1, the IMS includes an application server (10), a home subscriber server (HSS) 20, a call session control function (CSCF) 30, a mobile communication network (3G, and a general packet radio service (GPRS)). , CDMA 40, User Equipment 50, Media Gateway Control Function (MGCF) 60, Media Gateway (MGW) 70, PSTN 80, and the like.

Here, the HSS 20 (user information server) has the subscriber information and provides the corresponding subscriber information on request, and the CSCF 30 provides the incoming gateway, call control, serving profile management and address processing functions. Perform. The MGCF 60 is responsible for transmission control with an external public wired communication network (PSTN) 80 and the like, and the MGW 70 is for connection with a public wired communication network (PSTN) 80. GGSN (Gatway GPRS System Node) 41 is a wireless switching network so that when the wireless terminal is to perform a high-speed packet communication, the wireless terminal and the data exchange with the destination via a wireless switching network including a base station to access the general Internet network again Serving as a gateway for interworking with the Internet, the Serving GPRS Support Node (SGSN) 42 is responsible for tracking the mobile node, which becomes a tunnel for sending and receiving packets with the GGSN.

In the IMS shown in FIG. 1, each terminal may be connected to a different home network. The terminal and the home network are connected through a GGSN 41 / SGSN 42, which is a mobile communication network. In order to transmit / receive with other terminal devices, a session must be connected first, and after the session connection, data can be actually transmitted and received.

As shown in FIG. 1, the terminal device 50 performs applications 51 related to mobile communication, a protocol stack 52 for a series of control processes for communication control, and data transmission and reception. A communication module 53, a codecs 54 for data encoding / decoding, and a display unit 55.

The protocol stack 52 includes a Session Initialization Protocol (SIP) for session connection, Real Time Transport Protocol (RTP) / Real Time Control Protocol (RTCP), and a User Datagram Protocol (UDP), which are a protocol stack required for transmitting media. ) / Transmission Control Protocol (TCP) and Internet Protocol (IP). These are well-known standard protocols and will not be described in detail here.

In the IMS environment shown in FIG. 1, a user terminal (UE) 50 corresponding to a mobile terminal corresponds to an interface of an IP core network using the GGSN 41 / SGSN 42 of the existing mobile communication network. The CSCF 30 is connected. In the IP core network through the CSCF 30, the application server 10 for providing various applications and the HSS 20 (user information server) for managing user information as a database are linked. And various services. Details of each component are mentioned in detail in the relevant standard specification document and will be omitted here.

The standard specification introduces such a basic architecture, and specifically establishes a standard for signal processing using the CSCF 30 in detail. In addition, application-specific matters are left to each non-standard application.

Recently released mobile terminal devices are being equipped with displays of various sizes ranging from 128 × 96 small display windows to VGA (640 × 480). In addition, a decoder for reconstructing and reproducing an image or audio is provided for each terminal device. The embedded decoder may be different for each terminal device. For example, video standards such as MPEG1, MPEG2, MPEG4, H.263, H.264 are mainly used, and audio such as G.711, G.726, ARM, AAC, and MP3 are mainly used.

However, unlike a PC, a mobile terminal device does not include all of these standard decoders due to limited resources, and includes only some predetermined decoders. In some cases, even non-standard codecs may be included. Therefore, there is a general problem that mobile terminal devices for different operators are not compatible with each other. That is, when the specifications of the sending terminal apparatus and the specification of the receiving terminal apparatus are different, in particular, the multimedia resource transmitted from the transmitting terminal apparatus having a relatively high specification is received and reproduced by the receiving terminal apparatus having a relatively low specification ( Image display, audio playback, etc.).

For example, assuming that the transmitting terminal apparatus transmits at the QVGA (320 x 240) resolution, if the display of the receiving terminal apparatus can support only the QCIF (176 x 144), the receiving terminal apparatus retains the received data. It cannot be restored and displayed, and costs are increased because unnecessarily large data is received. For another example, if the performance of the sending terminal device is capable of recording QVGA 30fps video and then transmits it, but if the receiving terminal device supports only QVGA 7.5fps, the receiving terminal device supports the corresponding video data. Restoring to 1/4 performance results in a 4x slower display on display.

An object of the present invention is to provide a system that can implement a universal multimedia access environment capable of performing multimedia services according to characteristics of different terminal devices in an IMS environment defined by 3GPP standards organizations.

The present invention adapts a user terminal device to provide multimedia resource services at an optimal image quality and cost by adaptively adjusting the transmitted multimedia according to specifications such as a display size of a user terminal device or a supportable video frame rate. Its purpose is to provide a conventional transcoding system.

The present invention provides a system that enables a component plug-in to execute a decoder after real-time download when multimedia having a format that requires a decoder that is not included in a user's terminal device is transmitted. Its purpose is to.

The universal multimedia access system of the present invention for achieving the above object is adaptively converted according to the database containing the specification information of the user terminal device and the multimedia data to be transmitted according to the specification of the receiving terminal device of the database ( and an addressing means for performing transport packet addressing so that the application server is provided by transcoding and the multimedia data to be transmitted is converted and provided through the application server.

In addition, the universal multimedia access system of the present invention for achieving the above object, the user terminal device including its specification information and can transmit it, and receiving the specification data transmitted from the receiving terminal device to receive the multimedia data to be transmitted An application server adaptively transcoding according to the terminal terminal specification information, and addressing means for performing transport packet addressing so that multimedia data to be transmitted is converted and provided via the application server. do.

In addition, the universal multimedia access control method of the present invention for achieving the above object, when the multimedia data transmission is made, confirming the specification information of the receiving terminal device, and the multimedia data to the confirmed receiving terminal device specifications; And adaptively transcoding and transmitting the multimedia data converted according to the specification of the receiving terminal device.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of a universal multimedia access system in the IMS environment of the present invention.

In order to describe a feature for adapting a transcoding service to the above-described IMS environment, a general procedure for a transcoding service is briefly described as follows.

First, when the data is transmitted, the server needs to obtain the terminal device specification information of the receiving side, and then converting the transmitted data according to the specification of the receiving terminal device, and converting the converted data to the receiving side. The transmission may proceed. As described above, the application server including the transcoder needs to know the specification information of the terminal device for the transcoding service. In this case, the method of obtaining the specification of the terminal device is a method using an HSS or a SIP method. There are two ways.

[Method using HSS]

Figure 2 shows an embodiment configuration of a universal multimedia access system of the present invention using an HSS. As shown in FIG. 2, the universal multimedia access system in the IMS environment according to the present invention includes a transcoding application server 100, an HSS 200, a CSCF 300, a mobile communication network 400, and a user. Terminal device 500, MGCF (600), MGW (700), PSTN (800) and the like.

In FIG. 2, the application server 100 is a transcoding application server and includes a manager (UE spce info. Manager) and a transcoder 110 of user terminal specification information. In FIG. 2, the HSS 200 includes a UE Spec Database 210. In FIG. 2, the CSCF 300 includes an addressing module 310.

The HSS 200 provides subscriber information on request with subscriber information, and the CSCF 300 performs an incoming call gateway, call control, serving profile management, and address processing. The MGCF 600 is responsible for transmission control with an external public wired communication network (PSTN) 800, and the MGW 700 is for connection with a public wired communication network (PSTN) 800. The GGSN 410 is a gateway that interworks with a wireless switching network and an internet network so that a wireless terminal can perform data communication with a destination via a wireless switching network including a base station and again accessing a general internet network when a wireless terminal intends to perform high-speed packet communication. In this role, SGSN 420 is responsible for tracking the mobile node, which becomes a tunnel for sending and receiving packets with the GGSN.

In the IMS shown in FIG. 2, each terminal may be connected to a different home network. The terminal and the home network are connected through a GGSN 410 / SGSN 420 which is a mobile communication network. In order to transmit / receive with another terminal device, a session must first be connected, and after the session connection, data can be actually transmitted and received.

As described above, the HSS 200 is a master database for recording user information. Therefore, the database 210 may be configured to describe the user equipment specification of the user to the HSS 200. Subsequently, the application server 100 interoperates with the CSCF 300 to obtain the specification of the receiving terminal device from the database 210 of the HSS 200 and converts data to be transmitted according to the specification. In this case, since the user may change the terminal device 500, the database 210 information of the HSS 200 should be updated and maintained, but the user terminal device specification information recorded in the database 210 of the HSS 200 is updated. The update of may be performed by transmitting the update information including corresponding update information to the SIP used by the terminal device 500 to initialize a session at the start of transmission and reception. That is, it is possible to describe by updating the update information of the user terminal device in a predetermined field of the SIP, and to reflect this to the database 210 of the HSS 200 to modify the specification information for the terminal device.

 For reference, the terminal device 500 includes a step of connecting a session for data transmission and reception and RTP / RTCP which is a protocol used when transmitting and receiving data. This has been described with reference to FIG. 1 above. SIP and RTP / RTCP correspond to the session layer among the seven network layers defined by OSI, UDP or TCP correspond to the actual transport layer, and IP correspond to the network layer.

In order to convert the transmission data as described above, unlike the conventional method, the routing address in the packet must be changed so that the data is passed through the server so that the application server can obtain and convert the transmission data packet. For this service, an addressing module 310 is included in the IMS to allow the terminal device 500 to set a routing address of each packet through the corresponding application server. 2 illustrates a case in which the addressing module 310 is included in the CSCF 300. In addition, the transcoding application server 100 includes a module for taking the specification of the terminal device 500 from the HSS 200, and a conversion module for converting the data to be transmitted according to the interpretation of the corresponding terminal device specifications. . In FIG. 2, the terminal specification information manager and the transcoder 110 are represented.

[Method using SIP]

Figure 3 shows an embodiment configuration of a universal multimedia access system of the present invention using SIP. As shown in FIG. 3, the universal multimedia access system in the IMS environment according to the present invention includes a transcoding application server 100, an HSS 200, a CSCF 300, a mobile communication network 400, and a user terminal device 500. , MGCF 600, MGW 700, PSTN 800, and the like.

In FIG. 3, the application server 100 is a transcoding application server and includes a manager (UE spce info. Manager) and a transcoder 110 of user equipment specification information. In FIG. 3, the CSCF 300 includes an addressing module 310.

The HSS 200 provides subscriber information on request with subscriber information, and the CSCF 300 performs an incoming call gateway, call control, serving profile management, and address processing. The MGCF 600 is responsible for transmission control with an external public wired communication network (PSTN) 800, and the MGW 700 is for connection with a public wired communication network (PSTN) 800. The GGSN 410 is a gateway that interworks with a wireless switching network and an internet network so that a wireless terminal can perform data communication with a destination via a wireless switching network including a base station and again accessing a general internet network when a wireless terminal intends to perform high-speed packet communication. In this role, SGSN 420 is responsible for tracking the mobile node, which becomes a tunnel for sending and receiving packets with the GGSN.

In the IMS shown in FIG. 3, each terminal may be connected to a different home network. The terminal and the home network are connected through a GGSN 410 / SGSN 420 which is a mobile communication network. In order to transmit / receive with another terminal device, a session must first be connected, and after the session connection, data can be actually transmitted and received.

As shown in FIG. 3, the terminal device 500 includes an application 510 related to mobile communication, a protocol stack 520 for a series of control processes for communication control, and communication for data transmission and reception. Module 530, Codecs 540 for data encoding / decoding, Display unit 550, Spec information storage for storing the specification information of the corresponding terminal device to include the specification information of its own in the SIP ( 560, the specification information generating module 570 to include this in the SIP further. The protocol stack 520 includes SIP, RTP / RTCP, UDP / TCP, and IP.

In the IMS environment shown in FIG. 3, the user equipment 500 corresponding to the mobile terminal uses the GGSN 410 / SGSN 420 of the existing mobile communication network to provide the CSCF (corresponding to the interface of the IP core network). 300). In the IP core network through the CSCF (300), the application server (Application Server) (100) for providing a variety of applications (application) and the various services in connection with the HSS (200) for managing user information as a database do.

As described above, SIP is a protocol used when connecting an initial session, and may transmit and receive necessary information between a transmitting and receiving terminal device. When the transmitting side first connects to the CSCF 300 by SIP, the receiving side also connects to the CSCF by SIP to perform necessary signaling. At this time, it may include the specification of the receiving terminal device required for SIP transmitted from the receiving side. The specification of the terminal equipment can be expressed using a field predefined by the standard. That is, the specification information of the terminal device is described and expressed in a predetermined field predefined in the SIP by the standard, and the specification information described in the SIP is taken from the transcoding application server 100 and interpreted, and based on the corresponding terminal device. It is to know the specification of.

In the system of FIG. 3, in comparison with the system of FIG. 2 described above, the application server obtains and uses the information included in the SIP, instead of obtaining the specification of the receiving terminal device from the HSS 200. The rest of the procedure is the same as using the HSS. To this end, since the terminal device 500 needs to add its own spec information to the SIP and transmits it to the SIP, the spec information store 560 storing the spec information of the corresponding terminal device and the spec information generation module 570 including the same in the SIP. It contains more. Accordingly, the terminal device 500 describes the specification information by including its specification information in a predetermined field of the SIP in the specification generation module 570 using its specification information stored in the specification information storage 560 and transmits it. Thus, as described above, the specification of the terminal device by the transcoding application server 100 and the adaptive multimedia transcoding and transmission corresponding thereto are performed based on the SIP in which the specification information of the receiving terminal device is described.

Figure 4 shows the control procedure of the universal multimedia access system of the present invention described so far. The data transmission step (S41) is a step in which a transmitting terminal device intends to start transmitting a multimedia resource to a receiving terminal device. In the specification recognition step (S42), as described above, the application server obtains and interprets the specification information of the receiving terminal device from the specification information database of the HSS, or the receiving terminal device provided based on SIP in the receiving terminal device. It is a step of determining whether transcoding of the multimedia resource is necessary by recognizing and interpreting the specification information of the multimedia resource. The spec information may be device information including a display resolution, performance information of a processor, a video specification including a resolution and a frame rate, or a combination thereof.

If the multimedia resource to be transmitted meets the specification of the receiving terminal device, transcoding will not be required. Otherwise, the multimedia resource transcoding adaptive to the receiving terminal device is required. If transcoding is not needed, the multimedia resource does not need to go through a transcoding application server. In this case, therefore, the transmission data is controlled to be transmitted to the receiving terminal apparatus without passing through the transcoding application server. In other words, if the specification of the transmitted receiving terminal apparatus is suitable for the transmission data, and if it is determined that it is appropriate and no transcoding is necessary, the transport packet is addressed so that the transmission data does not pass through the application server, If it is determined that transcoding is necessary, then the transport packet is addressed so that the transport data passes through the application server.

Next step S43 is a step of converting the transmission data (multimedia resource) in accordance with the specification of the receiving terminal device. In this step, the corresponding multimedia resource is converted according to the specification of the receiving terminal apparatus. For example, the frame rate and resolution of video data are converted in accordance with the specifications of the receiving terminal apparatus. In the next step S44, the data (multimedia resource) converted according to the specification of the receiving terminal device is transmitted. The execution result of this step is to receive data such as a video converted to the specification of the receiving terminal device. You can listen and play without difficulty.

On the other hand, the following processing can also be performed from the acquired specification information of the receiving terminal device. That is, a system that enables component plug-in to execute the decoder after real-time download when multimedia having a format that requires a decoder not included in the user's terminal device is transmitted. .

To this end, when a decoder that does not include the receiving terminal apparatus is requested by the application server based on the specification information of the receiving terminal apparatus, the decoder downloads the decoder to the receiving terminal apparatus in real time and uses the multimedia data. Receive and play back.

Therefore, in this case, various kinds of decoders (decoding algorithms) corresponding to various multimedia formats should be constructed as a kind of database, and among the decoders provided therein, according to the format of the multimedia data to be transmitted and the specification of the receiving terminal device. The decoder is downloaded to the receiving terminal device, and playback is performed after the reception of the multimedia data based on the downloaded decoder.

The downloading of such a decoder (decoding algorithm) is performed automatically when there is no decoder capable of decoding the multimedia data as a result of checking the specification of the receiving terminal device, or only when the user accepts the receiving terminal device. You can also control it. That is, whether or not the decoder is downloaded is executed after receiving confirmation from the user of the receiving terminal device.

There are various types of transforms corresponding to the transcoding described above, but here, the frame rate and the resolution of the video are taken as an example. First, assuming that the transmitting terminal device transmits in QVGA (320 x 240) resolution, if the display of the receiving terminal device can support only QCIF (176 x 144), the receiving terminal device restores the received data as it is and displays it. Since it is impossible to do this, a separate reduction work must be performed, and the cost is increased because unnecessary data is received unnecessarily. To this end, resolution transcoding may be performed to convert to an appropriate resolution.

Next, if the performance of the sending terminal device is able to record QVGA 30fps video and transmits it, but if the performance of the receiving terminal device supports only QVGA 7.5fps, the receiving terminal device receives 1/4 of the video data. Restoring to performance causes the display to be displayed four times slower. In order to prevent this problem, frame rate transcoding is required to convert the frame rate. Through such frame rate conversion, the video data can be normally reproduced and displayed on the receiving terminal device.

The present invention proposes a method for realizing a transcoding service that optimally adjusts a frame rate or resolution of a multimedia resource in accordance with specifications of various terminal devices in an IMS environment. In particular, the present invention proposes a method of using the specification information of each terminal device to reduce the data transmission cost and optimize the processing of the terminal device, and provides two methods of exchanging information in real time through the method using the HSS and the method using the SIP. By proposing all the possibilities, it can be appropriately implemented in the environment of the multimedia resource transmission / reception system. Although the present invention has been described with reference to a video service, it proposes a method that can be extended to all multimedia resources.

Claims (18)

A receiving terminal apparatus, A user information server including a user information database storing user information and a specification information database of the receiving terminal device; An application server for adaptively transcoding and providing multimedia data to be transmitted according to specification information of a receiving terminal device of the database; And addressing means for performing transport packet addressing such that the multimedia data to be transmitted is converted and provided via the application server. According to claim 1, The application server means for adaptively converting the multimedia data according to the specification of the receiving terminal device, and connected to the database to obtain and interpret the specifications of the receiving terminal device based on the receiving side Universal multimedia access system comprising a means for controlling to convert the corresponding multimedia data in accordance with the specifications of the terminal device. 2. The universal multimedia access system of claim 1, wherein the user information server is an HSS in an IMS structure. 2. The universal multimedia access system of claim 1, wherein the addressing means is a CSCF in an IMS structure. The universal multimedia access system of claim 1, wherein the terminal specification information is device information including a display resolution, processor performance information, a video specification including a resolution and a frame rate, or a combination thereof. The method of claim 1, wherein adaptively transcoding the multimedia data to be transmitted according to specification information of the receiving terminal device of the database is controlled by adjusting the resolution, frame rate, or both according to the specification of the receiving terminal device. Universal multimedia access system, characterized in that. A receiving terminal apparatus including its own specification information and transmitting the same when the session is connected; An application server that receives the spec information transmitted during the session connection from the receiving terminal device and adaptively transcodes multimedia data to be transmitted according to the receiving terminal device specification information; Addressing means for performing transport packet addressing so that the multimedia data to be transmitted is converted and provided via the application server; And a user information server including a database for storing user information of the receiving terminal device. 8. The method of claim 7, wherein the application server is adapted to adaptively convert multimedia data according to the specification of the receiving terminal device, and receives and interprets the specification information from the receiving terminal device based on the received terminal device. Universal multimedia access system comprising a means for controlling to convert the corresponding multimedia data in accordance with the specification. The universal multimedia access system of claim 7, wherein the specification information transmitted from the terminal device is transmitted using SIP in an IMS structure. 8. The universal multimedia access system of claim 7, wherein the addressing means is included in a CSCF in an IMS structure. The universal multimedia access system of claim 7, wherein the terminal device specification information comprises device information including a display resolution, processor performance information, a video specification including a resolution and a frame rate, or a combination thereof. 8. The method of claim 7, wherein adaptively transcoding the multimedia data to be transmitted according to the specification of the receiver terminal device of the database adjusts the resolution, frame rate, or both according to the specification of the receiver terminal device. Universal multimedia access system, characterized in that. Receiving specification information of a receiving terminal device from a server including a user information database when the multimedia data transmission is made; Adaptively transcoding the multimedia data according to the received terminal equipment specification; And transmitting the multimedia data converted according to the specification of the receiving terminal device. 15. The universal multimedia access control of claim 13, further comprising determining whether the multimedia data passes through an application server for transcoding according to the confirmed receiving terminal specification. Way. 15. The method of claim 13, further comprising: determining whether the identified receiving terminal equipment specification is suitable for transmission multimedia data, and if the receiving terminal equipment specification is suitable for transmission multimedia data, applying the application server for transcoding. Addressing the transport packet so as not to pass through, and if not appropriate, addressing the transport packet via the application server. Authenticating a user by receiving user information from a server including a user information database; Receiving specification information of the receiving terminal device from a receiving terminal device in a session connection step; Adaptively transcoding the multimedia data according to the received terminal equipment specification; And transmitting the multimedia data converted according to the specification of the receiving terminal device. 17. The universal multimedia access control as claimed in claim 16, further comprising the step of determining whether the corresponding multimedia data passes through an application server for transcoding according to the received terminal specification. Way. 17. The method of claim 16, further comprising: determining whether the identified receiving terminal equipment specification is suitable for transmission multimedia data; Addressing the transport packet so as not to pass through, and if not appropriate, addressing the transport packet via the application server.

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