Live presentation searching

In a networked client/server system, live presentations can be streamed from an encoder or other server to a client computer. Additionally, information describing the presentation is registered with a search server. This information is made available for user searches only for as long as the information properly describes the live presentation. When the information no longer describes a current live presentation, the information is no longer available for searching.

TECHNICAL FIELD

This invention relates to networked client/server systems and to method of delivering and rendering live content in such systems. More particularly, the invention relates to searching for live presentations.

BACKGROUND OF THE INVENTION

The advent of computers and their continued technological advancement has revolutionized the manner in which people work and live. Information that used to be available only in written or verbal form is becoming increasingly available in electronic form. Furthermore, presentations which used to be available only on particular recording media (e.g., film or tape) or via television broadcasts are now available in digital form (e.g., over the Internet).

One problem encountered by users when faced with this continually increasing mass of digital information is the ability to locate particular information that the user is interested in. For example, trying to locate a particular presentation can be difficult and cumbersome for users. Various search mechanisms exist for pre-recorded “on-demand” presentations (e.g., various world wide web search engines). On-demand presentations are fairly easily searchable because the underlying data of the presentation is already known. However, in the case of live presentations, such underlying data is not known because, as the presentation is live, the underlying data is not available yet.

Some systems do exist that allow a user to identify scheduled live presentations. For example, a television programming guide may be available over the Internet that allows a user to search for television programs that are scheduled to be broadcast (e.g., via cable, satellite system, or typical television broadcast frequencies, such as UHF or VHF) and their associated broadcast times. However, such programming guides typically do not provide the flexibility to allow non-scheduled programs to be identified to the user. Furthermore, such programming guides are typically limited to television broadcasts and do not allow users to identify presentations from any of the wide variety of alternate sources (such as via the Internet).

The invention described below addresses these disadvantages, providing a way to search for live presentations.

SUMMARY OF THE INVENTION

In a networked client/server system, live presentations can be streamed from an encoder or other server to a client computer. Additionally, information describing the presentation is registered with a search server. This information is made available for user searches only for as long as the information properly describes the live presentation. When the information no longer describes a current live presentation, the information is no longer available for searching.

According to one aspect of the invention, the information describes the entire presentation. The information is available in the search server for user searches for the duration of the presentation. Once the presentation is over, the information is deleted from the search server, preventing any subsequent user search requests from being satisfied using the information describing that presentation.

According to another aspect of the invention, the information describes a particular characteristic(s) of the presentation (e.g., the current topic). The information for a characteristic is available in the search server for user searches for as long as that characteristic describes the portion of the presentation currently being presented. Once that characteristic no longer describes the portion currently being presented, the information describing that characteristic is deleted from the search server, preventing any subsequent user search requests from being satisfied using the information describing that characteristic.

According to another aspect of the invention, a user can register a notification request with the search server. The notification request identifies a set of search criteria as well as a manner in which the user should be notified in the event a live presentation matches the search criteria. The search server continues to compare new information regarding available live presentations to the search criteria. If a match is found, the search server notifies the user in whatever manner the user requested.

DETAILED DESCRIPTION

General Network Structure

FIG. 1shows a client/server network system and environment in accordance with one embodiment of the invention. Generally, the system includes multiple (n) network client computers102, multiple (m) encoders104, and a search server106. The computers102, encoders104, and server106communicate with each other over a data communications network. The communications network inFIG. 1is a public network108, such as the Internet. The data communications network might also include local-area networks and/or private wide-area networks, and can include both wired and wireless sections. Client computers102, encoders104, and server106can communicate with one another via any of a wide variety of known protocols, such as the Hypertext Transfer Protocol (HTTP).

Encoders104receive live content or presentations in the form of different media streams110. Encoders104can be dedicated media servers, or alternatively other more general-purpose computer systems. These media streams110can be individual media streams (e.g., audio, video, graphical, etc.), or alternatively can be composite media streams including two or more of such individual streams. The media streams110are provided to encoders on a “live” basis from other data source components through dedicated communications channels or through the Internet itself. Encoders104coordinate the streaming of the live content to other components on the network108that request the content, such as client computers102. It is to be appreciated that although the media streams are referred to as being “live”, there may be a delay (e.g., between one second and thirty seconds) between the time of the actual event and the time the media streams reach the encoder(s).

There are various standards for streaming media content and composite media streams. “Advanced Streaming Format” (ASF) is an example of such a standard, including both accepted versions of the standard and proposed standards for future adoption. ASF specifies the way in which multimedia content is stored, streamed, and presented by the tools, servers, and clients of various multimedia vendors. ASF provides benefits such as local and network playback, extensible media types, component download, scalable media types, prioritization of streams, multiple language support, environment independence, rich inter-stream relationships, and expandability. Further details about ASF are available from Microsoft Corporation of Redmond, Washington.

Encoders104can transmit any type of presentation over the network108. Examples of such presentations include audio/video presentations (e.g., television broadcasts or presentations from a “NetShow™” server (available from Microsoft Corp. of Redmond, Wash.)), video-only presentations, audio-only presentations, graphical or animated presentations, etc.

Search server106maintains a content database112, a notification database114, and a scheduled presentations database116. In content database112, server106maintains descriptive information regarding the current live content available from encoders104. A user of a client computer102can access search server106to search for particular live content. In notification database114, server106maintains information regarding users of client computers102that have registered to be notified when particular live content is available. In scheduled presentations database116, server106maintains information regarding future live presentations that have been registered with server106.

Exemplary Computer Environment

In the discussion below, the invention will be described in the general context of computer-executable instructions, such as program modules, being executed by one or more conventional personal computers. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the invention may be practiced with other computer system configurations, including hand-held devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. In a distributed computer environment, program modules may be located in both local and remote memory storage devices.

Alternatively, the invention could be implemented in hardware or a combination of hardware, software, and/or firmware. For example, the invention could be implemented in one or more application specific integrated circuits (ASICs).

FIG. 2shows a general example of a computer142that can be used in accordance with the invention. Computer142is shown as an example of a computer that can perform the functions of any of client computers102, server encoders104, or server106of FIG.1.

Computer142includes one or more processors or processing units144, a system memory146, and a system bus148that couples various system components including the system memory146to processors144.

The bus148represents one or more of any of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, and a processor or local bus using any of a variety of bus architectures. The system memory includes read only memory (ROM)150and random access memory (RAM)152. A basic input/output system (BIOS)154, containing the basic routines that help to transfer information between elements within computer142, such as during start-up, is stored in ROM150. Computer142further includes a hard disk drive156for reading from and writing to a hard disk, not shown, a magnetic disk drive158for reading from and writing to a removable magnetic disk160, and an optical disk drive162for reading from or writing to a removable optical disk164such as a CD ROM or other optical media. The hard disk drive156, magnetic disk drive158, and optical disk drive162are connected to the system bus148by an SCSI interface166or some other appropriate interface. The drives and their associated computer-readable media provide nonvolatile storage of computer readable instructions, data structures, program modules and other data for computer142. Although the exemplary environment described herein employs a hard disk, a removable magnetic disk160and a removable optical disk164, it should be appreciated by those skilled in the art that other types of computer readable media which can store data that is accessible by a computer, such as magnetic cassettes, flash memory cards, digital video disks, random access memories (RAMs) read only memories (ROM), and the like, may also be used in the exemplary operating environment.

A number of program modules may be stored on the hard disk, magnetic disk160, optical disk164, ROM150, or RAM152, including an operating system170, one or more application programs172, other program modules174, and program data176. A user may enter commands and information into computer142through input devices such as keyboard178and pointing device180. Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, or the like. These and other input devices are connected to the processing unit144through an interface182that is coupled to the system bus. A monitor184or other type of display device is also connected to the system bus148via an interface, such as a video adapter186. In addition to the monitor, personal computers typically include other peripheral output devices (not shown) such as speakers and printers.

Computer142operates in a networked environment using logical connections to one or more remote computers, such as a remote computer188. The remote computer188may be another personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to computer142, although only a memory storage device190has been illustrated in FIG.2. The logical connections depicted inFIG. 2include a local area network (LAN)192and a wide area network (WAN)194. Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets, and the Internet. In the described embodiment of the invention, remote computer188executes an Internet Web browser program such as the “Internet Explorer” Web browser manufactured and distributed by Microsoft Corporation of Redmond, Wash.

When used in a LAN networking environment, computer142is connected to the local network192through a network interface or adapter196. When used in a WAN networking environment, computer142typically includes a modem198or other means for establishing communications over the wide area network194, such as the Internet. The modem198, which may be internal or external, is connected to the system bus148via a serial port interface168. In a networked environment, program modules depicted relative to the personal computer142, or portions thereof, may be stored in the remote memory storage device. It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used.

Search Server

FIG. 3illustrates an exemplary search server in more detail. Search server106includes a query interface210, a registration interface212, a search engine214, and a database controller216. Client computers102(FIG. 1) communicate with search server106via query interface210. Query interface210allows users of client computers102to enter search criteria for live content. Upon receipt of a search request via query interface210, search engine214accesses content database112to search for live content that matches the search criteria.

Encoders104(FIG. 1) communicate with search server106via registration interface212. Registration interface212allows encoders104to provide descriptive information regarding the live content that they can stream to client computers. This descriptive information can then be added to content database112and used for searches by search engine214. Descriptive information can be maintained by server106for any live content that can be provided by encoders104.

Database controller216manages the databases112,114, and116. This management includes both adding entries to and removing entries from databases112,114,and116.

Live content or presentations available from encoders104can be either prescheduled or non-scheduled. Pre-scheduled presentations refer to presentations that have been registered with search server106as occurring in the future (e.g., not already in progress and not starting within the next five minutes). Descriptive information regarding pre-scheduled presentations (e.g., presentation title, key words describing the content of the presentation, and encoder(s) from which the presentation will be available) can be provided to server106from one of the encoders104or some other source, either via the network108(FIG. 1) or alternatively some other delivery mechanism (e.g., a magnetic or optical disk).

Non-scheduled presentations refer to presentations that have not been registered with search server106as occurring in the future. A non-scheduled presentation is registered with server106as the presentation is about to begin (e.g., within the next five minutes) or shortly after it has begun. The presentation can be registered by an encoder104(e.g., the encoder104that will be streaming the live content), or alternatively some other source. As part of the registration process, server106is provided with descriptive information regarding the presentation.

FIG. 4illustrates entries of an exemplary content database in more detail.FIG. 4is described with additional reference to components in FIG.3. Each entry in content database112includes data for one or more of the following fields: title230, source232, duration234, current characteristic(s)236, and descriptive information238. Content database112can be stored in volatile memory (e.g., RAM), non-volatile memory (e.g., a magnetic disk drive), or a combination thereof.

Title field230includes a descriptive title of the presentation. Source field232identifies the encoder(s)104from which the presentation can be obtained. Duration field234identifies, for some entries, the duration of the presentation; in other entries, the duration data is not included. Characteristics field236optionally identifies the current characteristics for the presentation (i.e., one or more characteristics describing the portion of the presentation currently being presented or about to be presented). Any of a wide variety of characteristics can be included for the presentation, such as the current topic (as illustrated in FIG.4), the name of the current speaker, the gender of the current speaker, the color of the current speaker's clothing, etc. Descriptive information field238provides various descriptive information that describes the content of the presentation.

Content database112maintains information identifying each of the currently available live presentations that is registered with server106. Information regarding pre-scheduled presentations that are not currently available (or shortly will be available) from an encoder104is maintained in scheduled database116. Alternatively, such information could be included in content database112and simply marked as “invalid” until the presentation is available from an encoder104.

In the illustrated example, each current live presentation has an associated entry in database112. When a pre-scheduled presentation is about to begin (e.g., it is scheduled to begin shortly, such as within two minutes), database controller216(FIG. 3) loads descriptive information corresponding to the presentation into an entry of database112. In the case of pre-scheduled presentations, this descriptive information is loaded from pre-scheduled presentations database116. In the case of non-scheduled presentations, this descriptive information is received directly from registration interface212.

When a presentation is over, the entry in database112corresponding to the presentation is deleted. Server106is provided with an indication of the duration of a live presentation from the encoder or other device that registered the presentation with server106. In one implementation, this indication of the duration is a time period or “run time” for the presentation. For example, an encoder may indicate that a particular live presentation is going to be available between 2:00 p.m. and 4:00 p.m. on Jan. 1, 2000, or that a particular live presentation is going to last for 45 minutes. Database controller216monitors content database112for presentations whose time period or “run time” has passed, and deletes the corresponding entries from database112. According to another implementation, this indication of the duration of the presentation is simply a “presentation over” message or similar indicator. For example, an encoder may register for a current live presentation, and then send a “presentation over” message to the server106when the presentation has completed. Upon receipt of the “presentation over” message, database controller216deletes the entry corresponding to the presentation from database112.

In one implementation of the invention, database controller216also includes a timeout control that monitors the length of time that entries have been in database112. If a “presentation over” message is not received for a live presentation within a default period of time, then controller216assumes that a “presentation over” message was mistakenly not sent (or was lost in transit) and removes the entry corresponding to the live presentation from database112.

Additionally, in another implementation of the invention a presentation that is scheduled for a particular duration (e.g., 90 minutes, or from 2:00 p.m. to 4:00 p.m.) may be extended. The duration can be extended by the encoder104(or other device) sending a message to server106to change the duration in the corresponding entry of database112. For example, the message may indicate to change “90 minutes” to “110 minutes”, or to change “2:00 p.m. to 4:00 p.m.” to “2:00 p.m. to 5:00 p.m.”. Alternatively, the duration may be extended by the encoder104(or other device) sending a message to server106indicating that server106is to ignore the previously identified duration and that a “presentation over” message or similar indicator will be transmitted to server106when the presentation is over.

The descriptive information field238of an entry includes data that describes the content of the corresponding presentation. In the illustrated example ofFIG. 4, the data includes a set of one or more key words describing the presentation. Alternatively, the data could include a summary or abstract of the presentation, or a textual transcript of the presentation.

The data for descriptive information field238can be generated manually or automatically. Manual generation refers to an individual (e.g., the presentation author) creating the data. For example, the author may write a summary or a list of key words for the presentation and provide them to server106(either directly or via an encoder104).

Automatic generation refers to one of the components, such as an encoder104or server106, using any of a variety of mechanisms to generate data describing the presentation as the presentation occurs. For example, conventional key word generation processes may be employed to identify key words from the presentation. This may be carried out by an encoder104, server106, or some other component coupled to network108. By way of another example, closed captioning information may be used as the data, or conventional speech-to-text conversion techniques may be used to convert audio data into text data.

The information maintained in content database112is used by search engine214to respond to search requests received from users of a client computer102(FIG.1). A user provides, as part of his or her search request, a set of search criteria and which fields the search criteria should be applied to. The user can provide search requests via any of a wide variety of conventional input mechanisms, such as a graphical user interface (GUI). In the illustrated example, the user is able to search any of the fields in content database214. Search engine214compares the user-provided search criteria to each entry in the database112to determine whether the presentation corresponding to the entry satisfies the search request. Any of a variety of conventional searching algorithms and methodologies can be used. For example, any entry with at least one word matching one of the search criteria may satisfy the search request, an entry may be required to include every word in the search criteria in order to satisfy the search request, etc.

Information regarding presentations that satisfy a search request are provided to the client computer102of the user that placed the request. Such information may be the entire entry from database112, or alternatively a selected portion (e.g., the title field230and source field232for the entry). The source field232is provided to the client computer to allow the user to subsequently request the presentation, via the client computer, from the appropriate encoder104. In the illustrated example, the data in source field232comprises a uniform resource locator (URL) that identifies a particular presentation available from a particular encoder.

Information from each entry that satisfies the search criteria is provided to the user and, if multiple entries satisfy the each criteria, then the user can select one or more presentations based on this information. Alternatively, server106may rank the entries based on how well they match the search criteria and return information for only the highest ranking entry (or entries) to the user.

In addition to information describing the overall content of the presentation, current “characteristic” information is also (optionally) included in database112. Characteristic information describing one or more current characteristics of the presentation is registered with search server106by the encoder104. When one or more of the current characteristics changes, the encoder104registers the new current characteristic(s) with server106. Server106, in response, changes the entry in content database112corresponding to the presentation to identify the new current characteristics (e.g., by replacing one or more of the current characteristics or by adding a new characteristic(s)). By continually updating the current characteristics, a user can search for particular characteristics without regard for which actual presentation includes the characteristics. For example, a user may be interested in discussions of Microsoft Corporation and can search for the characteristics “Microsoft” or “Bill Gates” across multiple presentations registered with server106.

A current characteristic has a duration analogous to that of the presentation discussed above. Each characteristic may have its own duration, or multiple characters for a presentation may have the same duration. The duration of the characteristics can be identified explicitly (e.g., the author may indicate that Microsoft Corporation will be discussed from 2:07 p.m. to 2:12 p.m., or that the current characteristic of Microsoft Corporation will be accurate for the next seven minutes, or a “characteristic over” indicator (such as a “cancel characteristic” message) may be transmitted to server106from encoder104). Alternatively, the duration of the characteristics can be identified implicitly (e.g., the previous current characteristics are over when new current characteristics information is received).

Current characteristics data can also be generated either manually or automatically, analogous to the generation of data for descriptive information field238discussed above. For example, an algorithm may use closed captioning data or a speech-to-text conversion algorithm to obtain a textual version of the presentation. Key words can then be identified from the textual version and if their frequency is high enough (e.g., the word “Microsoft” occurs at least a threshold number of times, such as ten, within a period of time, such as sixty seconds or every 500 words), then those key words are identified as the current topic data.

Current characteristics information can be deleted from database112in an immediate manner. That is, as soon as new current characteristics data is received, the previous current characteristics data is deleted. Alternatively, the current characteristic information may be “aged out” of database112gradually. For example, if new current characteristics are identified and the key words that caused the identification of the previous current characteristics are not detected within a threshold amount of time (e.g., ten minutes), then the previous current characteristics are deleted from database112. This aging out can be implemented by server106, or alternatively can be used by encoder104in determining when to transmit a “characteristic over” indicator to server106.

Thus, using characteristics, it can be seen that the results of a search request can vary depending on when during the presentation the search request is made.

Alternatively, the current characteristics for a presentation can be displayed to the user rather than used for searching. For example, a user may submit a search request that results in multiple live presentations with descriptive information238satisfying the search criteria. Search server106transmits the current characteristics for each of these matching live presentations (as well as other information, such as title230) to client102for display to the user. Search server106also transmits any changes in the current characteristics for these matching live presentations to client102. Thus, client102presents to the user a continually updating display of the current characteristics of the live presentations that satisfy his or her search request.

Database controller216also maintains notification database114. A user can register a “notification request” with server106that includes a search request and a notification type. The search request includes the user's search criteria and the notification type identifies how the user wants to be notified in the event a live presentation begins that matches the search criteria. In one implementation, a user can register an email address, a pager number, a cellular phone (or other telephone) number, etc.

Database controller216receives the notification request and places the search criteria and notification type in notification database114. Database controller216also invokes search engine214to determine whether any current entry in content database112satisfies the search criteria. If a match is found, then the user is notified in a manner according to the notification type. The notification request may then be removed from notification database114, or alternatively left in notification database114to detect subsequent matches.

If a match is not immediately found, then database controller216continues to invoke search engine214each time new information is placed in content database112. Once invoked, search engine214determines whether the new information results in an entry that matches any of the search criteria of notification requests in notification database114. This search may be compared to all entries in content database112, or alternatively only to the entries in database112that include the new information.

FIG. 5shows exemplary steps in a process for allowing searching of live presentations. Steps on the left side of dashed line250are carried out by an encoder104ofFIG. 1, and steps on the right side of dashed line250are carried out by search server106of FIG.1. These steps may be performed in software.FIG. 5is described with additional reference to components in FIG.1.

Initially, encoder104sends identifying information for a current live presentation to search server106(step252). This identifying information is received by server106(step254), which records the information and makes the information available for user searches (step256). The identifying information is used by server106in responding to any subsequent search requests it receives (step258).

While server106is performing steps254-258, encoder104continues to stream the live presentation to any of the client computers102that request it until the presentation is over (steps260and262). When the presentation is over, encoder104stops streaming the presentation to client computers102and sends a “presentation over” indication to server106(step264).

Server106receives the “presentation over” indication from encoder104(step266) and deletes its record of the identifying information regarding the presentation (step268). Thus, any subsequent search requests will not be compared to the identifying information for that presentation, as that presentation is over.

Alternatively, rather than relying on a “presentation over” indication in step266, server106may be informed of the end of the presentation in other manners (such as a pre-programmed duration).

FIG. 6shows exemplary steps in a process for allowing searching of current characteristic information in live presentations. Steps on the left side of dashed line280arc carried out by an encoder104ofFIG. 1, and steps on the right side of dashed line280are carried out by search server106of FIG.1. These steps may be performed in software.FIG. 6is described with additional reference to components in FIG.1.

Initially encoder104sends, to search server106, current characteristic(s) information for the portion of a live presentation currently being presented (step282). Search server106in turn receives the current characteristic(s) information (step284). Server106records the current characteristic(s) information and makes the information available for searching (step286). The characteristic(s) information is used by server106in responding to any subsequent search requests it receives (step288).

While server106is performing steps284-288, encoder104continues to stream the live presentation to any of the client computers102that request it (step290). Encoder104also checks whether the current characteristic(s) are over (step292). When the current characteristic(s) are over (e.g., they no longer describe the portion of the live presentation currently being presented), encoder104sends a “characteristic(s) over” indication to server106(step294).

Server106receives the characteristic(s) over indication from encoder104(step296) and deletes its record of the characteristic(s) information (step298). Thus, any subsequent search requests will not be compared to the characteristic(s) information for that presentation, as those characteristic(s) are over.

Conclusion

The invention allows for the searching of live presentations. An encoder providing a live presentation registers with a search server, advantageously making information identifying the presentation available for searching only for the duration of the presentation. Additionally, characteristic information identifying current characteristic(s) of the presentation can be registered with the search server only for the duration of that characteristic(s). Thus, the characteristic information is advantageously made available for only as long as that characteristic(s) describes the current portion of the live presentation.