KR20060100002A - Detecting system and method for media file in network - Google Patents

Abstract

The present invention relates to a system and method for retrieving a media file, and more particularly, to search and provide contents (media files) in a plurality of UPnP AV servers existing on a UPnP network through a specific UPnP AV server. There is this. To this end, the present invention provides a plurality of media servers 231 to 233 for providing a media file, a media renderer 220 for receiving and playing arbitrary media files, the media renderer 220 and a plurality of media servers ( In the UPnP AV network having a control point 210 for controlling the media files 231 to 233 to play a media file selected by the user, the media server 231 includes a plurality of media servers 232, 233 to discover and obtain media information from the found multiple media servers 232 and 233 and to provide its own media information and multiple media information obtained from the multiple media servers 232 and 233. Agent 240 is configured.

Description

DETECTING SYSTEM AND METHOD FOR MEDIA FILE IN NETWORK}

1 is a block diagram of a general UPnP AV architecture.

2 is a block diagram of a system for an embodiment of the present invention.

Figure 3 is an exemplary view showing a media file directory structure in the present invention.

4 is an operation flowchart according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

210: control point (CP) 220: media renderer

231 to 233: Media server 240: CP agent

The present invention relates to home networking technology, and more particularly, to a system and method for retrieving a media file.

Recently, as computing power is applied to small and various devices, cheap and universal networking media technologies are emerging or commercialized. For example, a variety of devices such as refrigerators, TVs, washing machines, PCs, and audio devices used in homes are connected by networking and given the computing power to make it easier to use and set up so that people can enjoy higher quality of life. I could enjoy it.

(이하, UPnP라 약칭함)이 제시되었다. Since the Plug and Play (PnP) feature has been added to the current operating system, installing and configuring PC peripherals has become much easier, but these convenient features can be transferred to the entire network based on Internet standard technologies such as TCP / IP, HTTP, and XML. Is a technology that enables home networking for network devices such as home appliances, network printers, and Internet gates.

(Hereinafter abbreviated as UPnP) has been presented.

UPnP is one of the technologies for connecting small and various devices to a network.

Currently, the UPnP AV architecture, as shown in FIG. 1, controls a Control Point (CP) 110, a Media Server (MS) 130 that provides content, and plays the content. A media renderer (MR) 120 is provided.

The media renderer 120 actually plays the media using the information provided from the media server 130. In this case, the content type that the media renderer 120 can receive depends on a transfer protocol and a data format supported by the media renderer 120.

The media server 130 not only stores and stores media information such as music, movies, and photos, but also informs media information or transmits a media file at the request of the control point 110. In this case, the media server 130 provides at least one transfer protocol and data formats for each content item. In addition, the media server 130 may convert a format of a given content item into another format and transmit the same.

The control point 110 adjusts or manages operations of the media server 130 and the media renderer 120 according to a user's command. That is, the control point 110 manages a plurality of media renderers 120 and a plurality of media servers 130 which are UPnP devices to perform a predetermined operation in a UPnP scenario, and coordinates the operations of each device so as not to interfere with each other. Play a role.

Therefore, when the user selects the content of the media server 130 using the user interface (UI) of the control point 110 and selects the media renderer 120, the selected content is out of band. is directly transferred to the media renderer 120 using an of-Band transfer protocol.

Meanwhile, in the UPnP standard, direct communication with the actual media is performed using a content directory service (hereinafter, referred to as "CDS"), and respective actions and events are defined for this purpose.

In general, there are two main methods for implementing the CDS.

First, a method of using a specific data structure in memory is a method of processing the actual media file management on the memory by reading the information of the media file stored on the recording medium into the memory. This first method is characterized in that the data structure of the entire media file is uploaded and used on the memory. If there is no change of information on the media file media, no I / O operations are performed on the file media. Faster, and in-memory processing is much more flexible than file processing, so there is an advantage in that the current data structure needs to be modified a little without the need for extra processing to store specific metadata.

The second method is to create response data by taking the information directly from the recording medium whenever a specific action request is received from the client without storing the media information in memory. This second method is characterized by collecting actual information by accessing the media where the data is located when an action is received from the client without creating any administrative data structure in memory. The advantage is that it is small and simple to implement, and that the information is obtained directly from the actual media file, eliminating the need for additional refresh or synchronization operations that occur when using memory data structures.

In other words, the CDS enables viewing of content that the media server 130 can provide to the home network.

In this case, the control point 110 may obtain detailed information such as name, creation date, size, etc. of the content item provided by the media server 130 using the CDS.

Accordingly, the control point 110 checks whether the media renderer 120 can render the corresponding content by using the obtained detailed information.

In other words, the UPnP AV standard provides the UPnP AV control point with various information about the media file owned by the media server through the CDS service, and the UPnP AV control point performs a browse action using Object ID as an input variable. You can get that information by calling it.

However, in the related art, even if multiple media servers exist on the UPnP network, the control point (CP) can obtain the information of the media file from each media server or only the information of the media file existing in one media server. As a result, the media processing speed is lowered.

That is, conventionally, any media server has a disadvantage in that it cannot provide a media file being serviced by another media server on a UPnP network.

If there is a method for exchanging media file information between UPnP AV servers, the control point (CP) can access a single media server and obtain information on all media files on the UPnP network.

Accordingly, the present invention searches for a media file created to search and provide contents (media files) in a plurality of UPnP AV servers existing on a UPnP network through a specific UPnP AV server in order to improve the conventional disadvantage. Its purpose is to provide a system and method.

In order to achieve the above object, the present invention provides a network system in which a plurality of media servers, at least one or more media renderers, and a control point exist. And a CP agent mounted on a specific media server to obtain media information from the media server and to provide its media information and a plurality of media information obtained from the plurality of media servers.

In addition, the present invention provides a method for retrieving a media file in a network in which a plurality of media servers, including at least one media renderer, and a control point, including a specific media server equipped with a CP agent, The specific media server checking whether there is a content directory service (hereinafter referred to as "CDS") action from the control point, and if there is the CDS action, calling a CDS action on the network to find a plurality of media servers and discovering Acquiring media information from a plurality of media servers, and aligning the obtained media information with its own media information and transmitting the media information to the control point.

Therefore, in the UPnP AV network using the Asynchronous-Pull Transfer Protocol, the control point searches only a specific media server on the UPnP network without expanding the control point (CP), so that media files of various media servers can be found. Information can be obtained at once.

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

2 is a block diagram of a media file search system according to an exemplary embodiment of the present invention. As shown in FIG. 2, a plurality of media servers 231 to 233 which provide a media file, and an arbitrary media file are provided for playback. In the UPnP AV network having a media renderer 220, a control point 210 for controlling the media renderer 220 and a plurality of media servers (231 to 233) to play any media file selected by the user, The media server 231 discovers a plurality of media servers 232 and 233 present on the network, obtains media information from the found plurality of media servers 232 and 233, and has its own media information and a plurality of media. CP agent (240) is provided to provide a plurality of media information obtained from the server (232, 233).

Referring to the operation and effect of the embodiment of the present invention configured as described above are as follows.

In the initialization process of the UPnP media servers 231 to 233, the specific media server 231 confirms in advance the existence of the media servers 232 and 233 existing on the network. This is because the media server 231 receives the description information of the media server newly added to the network as a multicast message and stores the newly added media server.

In addition, the media server 231 identifies the media server existing in the network by multicasting the M-SEARCH message to the network at the time of being connected to the network.

The operation of FIG. 2 will be described on the assumption of the above condition.

When the control point 210 requests the media file search to the media server 231, the media server 231 checks whether the media file requested by the control point 210 exists on its own disk, and corresponds to its own disk. If the media file does not exist, a search request is made to the media servers 232 and 233 where the object exists.

To this end, the media server 231 is equipped with a CP agent (240).

Here, assuming that the requested media file exists in the media server 233, the media server 233 transmits the result of the search request to the media server 231.

The media server 231 transfers the results from the media server 233 to the control point 210.

Accordingly, when the user confirms the received information and selects the playback of the media file, the control point 210 calls the CM: PrepareForConnection () action to the media server 231, and the media server 231 requests the request. The action is delivered to the media server 233 to prepare a connection for playback.

The control point 210 calls the CM: PrepareForConnection () action to the media renderer 220 to prepare a connection for playback.

Thereafter, when the control point 210 calls the AVT: SetAVTransportURL () and AT: Play () actions to the media renderer 220, the media renderer 220 directly downloads the stream of the media file from the media server 233. Receive and play.

Meanwhile, the CDS-based media file has a tree structure as shown in FIG. 3, which will be described below.

Under the root container, media files existing in the local media server 231 as well as media files existing in other media servers 232 and 233 on the same network exist as "child".

When a search request is received from the control point 210 for objectID = "0", the media server 231 "roots" the root of the content directory of other media servers 232 and 233 on the network. Including as and delivers the search results to the control point (210).

That is, objects existing on the local disk are attached as "child" at the root as before.

The objectID of a media file existing in another media server is distinguished from the local media file by prefixing to identify the media server in which the object exists. For example, the prefix is added as <MS Name>: <Item Name>.

Referring to Figure 4 again the process performed in an embodiment of the present invention will be described.

FIG. 4 illustrates a series of control points 210 in which a plurality of media servers exist on an Asynchronous-Pull UPnP network to communicate with only one specific media server to obtain media file information from another media server. The process is illustrated.

First, the control point 210 requests the media server 231 to search for a media file.

The media server 231 checks whether the requested object exists on the local disk. The media server 231 may check whether the requested object exists on its own disk or another media server 232 through the prefix used for the object name.

The media server 231 transfers the search result directly to the control point 210 when the object requested by the control point 210 is stored in its disk.

If the requested object exists in another media server (232 in FIG. 4) on the network, the media server 231 requests a search instead of the control point 210 to the media server 232 in which the object exists. In this case, it is possible to know which media server to search by using prefix information attached to the object name.

The media server 232 transfers the information of the object existing on the local disk to the media server 231.

The media server 231 transfers the information of the object to the control point 210. In this case, the object name is not used as the value transmitted by the media server 232, but the control point 210 is prefixed with a prefix that can indicate that the object exists in the media server 232. To pass.

Thereafter, when play of any media file existing in the media server 232 is set, the control point 210 calls the CM: PrepareForConnection () action to the media server 231.

In this case, the media server 231 transmits the action request to the media server 232, receives the result of the action, and delivers the result of the action to the control point 210.

Accordingly, the connection of the media server 232 where the actual object exists is prepared.

Although a communication process between the control point 210 and the media renderer 220 is omitted in FIG. 4, this process is the same as that described in the UPnP AV architecture.

Thereafter, the stream transmission of the media file is performed directly between the media server (one of 231 to 233) and the media renderer 220 where the object exists.

That is, according to the present invention, in the asynchronous-pull transmission scheme, the control point (CP) can communicate with one specific UPnP AV server at the same time without a function extension so as to simultaneously communicate with a plurality of UPnP AV servers. This allows you to search for content existing on the AV server at once.

In the above-described preferred embodiment of the present invention, the CP agent 240 is mounted only on the media server 231 to retrieve media file information of other media servers 232 and 233 in response to a request of the control point 210. Although the case of returning to 210 has been described, the CP agent may be mounted on the media server 232 or 233 or the CP agent may be mounted on all of the media servers 231 to 233 on the network. This means that those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

As described in detail above, the present invention enables UPnP through a single media server by allowing a control point (CP) to communicate with a media server using UPnP AV technology, thereby allowing data to be exchanged between a plurality of media servers in a predetermined manner. By enabling communication with a plurality of UPnP AV servers existing on the network at one time, the media processing speed can be improved.

Claims (6)

In a UPnP network system in which a plurality of media servers, at least one media renderer, and a control point (CP) exist, CP agent that discovers a plurality of media servers existing on the network, obtains media information from the found multiple media servers, and provides its own media information and a plurality of media information obtained from the multiple media servers. A media file retrieval system characterized by being mounted on a specific media server. The method of claim 1, wherein the particular media server Check whether the media file requested from the control point is owned, and if the media file is found to exist on another media server, request the media server information from the media server and deliver the information to the control point. Media file retrieval system. The media file retrieval system according to claim 2, wherein the media file information is transmitted to the control point with a prefix indicating a media server where the media file exists. The method of claim 1, wherein the particular media server The control point is configured to receive the playback command requested by the control point and deliver it to the media server. A method for retrieving a media file in a network in which a plurality of media servers including a specific media server equipped with a CP agent, at least one media renderer, and a control point exist, Identifying, by the specific media server, an action for retrieving media file information from a control point; If the action is confirmed, the specific media server checks whether the information of the owned media file, and If it is determined that the media file is not owned by the specific media server, calling the media file search action on a network to obtain corresponding media file information from another media server; And transmitting the obtained media file information to the control point. 6. The method of claim 5, wherein the media file information is prefixed with a media server.

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