text: the present invention provides contextual search and query refinement for ce devices , wherein a cognitive load of query formation is relegated to the device itself , freeing the user to simply enjoy the content . the device then uses that context for query formation , as well as result filtering on behalf of the user . in one example implementation involving a local area network , metadata related to local content and current application states are gathered . the application states include user application states such as the current device ( s ) activity , for example , playing a music cd , playing a dvd , etc . the gathered data is then used to obtain the context for query formation and result filtering , essentially without user intervention . in this example , the user application states , the local context , and optionally , additional contextual terms derived from external sources ( e . g ., the external network ), are utilized to form an appropriate query . the query is submitted to a search engine and the results are presented to a user . preferably , contextual information is used to refine the search results returned by the search engine so that the search results are more likely to satisfy the user request . fig1 shows a functional architecture of an example network 10 , such as a local network ( e . g ., a home network ) embodying aspects of the present invention . the network 10 comprises devices 20 which may include content , ce devices 30 ( e . g ., a cell phone , pda , mp3 player , tv , vcr , stb , etc .) which may include content , and an interface device 40 that connects the network 10 to an external network 50 ( e . g ., another local network , the internet , etc .). though the devices 20 and 30 are shown separately , a single physical device can include one or more logical devices . the devices 20 and 30 , respectively , can implement the upnp protocol for communication therebetween . those skilled in the art will recognize that the present invention is useful with other network communication protocols such as jini , havi , 1394 , etc . the network 10 can comprise a wireless network , a wired network , or a combination thereof . referring to the flowchart in fig2 , each of the devices 20 and 30 can implement an example contextual search and query refinement process 200 according to the present invention , which includes the steps of : step 202 : extracting contextual information indicating current user activity from application states in the local network . step 204 : extracting contextual information about the content in the local network , from metadata sources in the local network . step 206 : extracting contextual information about the content in the local network , from metadata sources in an external network . step 208 : deriving additional contextual information from the extracted contextual information . step 210 : extracting additional contextual information about the content in the local network from results obtained from the external network . step 212 : forming an appropriate query based on the obtained contextual information , and performing a search based on the query . step 214 : using the contextual information to guide the selection of desired content from the search results . in one example , step 204 described above for extracting contextual information , includes the further steps of : ( a ) extracting contextual information from one or more of the following sources : ( i ) the user &# 39 ; s current activity indicated by the states of applications running on devices in the local network ( e . g ., the user is playing media in a cd player , wherein the type of content being played is “ music ”); and ( ii ) metadata about the content available in the local network , from one of the following sources : ( 1 ) the metadata sources in the local network ( e . g ., id3 tags from a local mp3 player ); ( 2 ) the metadata sources over the external network ( e . g ., the album , the artist etc ., information from a compact disc database ( cddb )); ( 3 ) the metadata embedded in available content ( e . g ., closed captions ), etc . ; and ( b ) deriving additional contextual information from the obtained contextual information . in one example , given a current activity that is “ playing music title : brand new day by artist : sting ,” it is deduced that sting may have a “ biography ” and “ brand new day ” may have “ lyrics .” in addition , in step 214 using the obtained contextual information to guide the selection of the most relevant content from the search results can further include forming an appropriate query from the obtained ( extracted ) contextual information , by : ( a ) using a subset of terms from the obtained contextual information to form a query . for example , “ music artist sting biography age debut .” ( b ) using the obtained contextual information to guide the selection of the most relevant content from the search results . for example , while searching for “ sting discography ,” search results that do not contain the album “ brand new day ” are ignored because from the local content , it is known that one of the albums by sting is called “ brand new day .” fig3 shows a functional block diagram of an example system 300 implementing such a contextual search and query refinement process , according to an embodiment of the present invention . the system 300 shows specific components that derive and use contextual information to form a query and to filter the search results for presentation to a user , as described . the system 300 utilizes the following components : broadcast unstructured data sources 301 , a local contextual information gatherer 302 , a local metadata cache 303 , a contextual information deriver 304 , a correlation framework 305 , a broadcast data extractor and analyzer 306 , local content sources 307 , document theme extractor 308 , application states 309 , a client user interface ( ui ) 310 , a query execution planner 312 , a correlation plan executor 314 , a correlation constructor 316 , an internet metadata gatherer from structured sources 318 , internet structured data sources 320 , a query 322 , a search engine interface 324 , web pages 326 , a snippet analyzer 328 , and internet unstructured data sources 330 . the function of each component is further described below . the broadcast unstructured data sources 301 comprises unstructured data embedded in media streams . examples of such data sources include cable receivers , satellite receivers , tv antennas , radio antennas , etc . the local contextual information gatherer ( lcig ) 302 collects metadata and other contextual information about the contents in the local network . the lcig 302 also derives additional contextual information from existing contextual information . the lcig 302 further performs one or more of the following functions : ( 1 ) gathering metadata from local sources whenever new content is added to the local content / collection , ( 2 ) gathering information about a user &# 39 ; s current activity from the states of applications running on the local network devices ( e . g ., devices 20 , 30 in fig1 ), and ( 3 ) accepting metadata and / or contextual information extracted from internet sources and other external sources that describe the local content . the lcig 302 includes a contextual information deriver ( cid ) 304 which derives new contextual information from existing information . for this purpose , the cid 304 uses a local taxonomy of metadata related concepts . an example partial taxonomy 400 is shown in fig4 . each edge 402 ( solid connector line ) connects a pair of concepts 404 ( solid ellipses ). an edge 408 between a pair of concepts 404 represents a has - a relationship between that pair of concepts 404 . each edge 408 ( dotted connector line ) connects a concept 404 and a synonym 406 ( dotted ellipse ), and represents a is - a relationship therebetween . as such , each edge 408 connects a concept 404 with its synonym 406 . in one example where the current information need is about a music artist , the cid 304 uses the taxonomy 400 to determine “ biography ” and “ discography ” as derived contextual terms . the cid 304 also knows that “ age ” and “ debut ” are relevant concepts in an artist &# 39 ; s biography . referring back to fig3 , the lcig 302 further maintains a local metadata cache 303 , and stores the collected metadata in the cache 303 . the cache 303 provides an interface for other system components to add , delete , access , and modify the metadata in the cache 303 . for example , the cache 303 provides an interface for the cid 304 , local content sources 307 , internet metadata gatherer from structured sources 318 , broadcast data extractor and analyzer 306 , document theme extractor 308 and snippet analyzer 328 , etc ., for extracting metadata from local or external sources . the broadcast data extractor and analyzer ( bdea ) 306 receives contextual information from the correlation framework ( cf ) 305 described further below , and uses that information to guide the extraction of a list of terms from data embedded in the broadcast content . the bdea 306 then returns the list of terms back to the cf 305 . the local content sources 307 includes information about the digital content stored in the local network ( e . g ., on cd &# 39 ; s , dvd &# 39 ; s , tapes , internal hard disks , removable storage devices , etc .). the document theme extractor ( dte ) 308 receives contextual information from the cf 305 as input and performs one or more of the following operations guided by the contextual information : ( 1 ) extracting and selecting a list of terms that best summarize the themes of documents returned as search results by the search engine interface 324 , and returning the list to the cf 305 , and ( 2 ) clustering the documents returned as search results , extracting and selecting therefrom a list of terms that best summarize the themes of each cluster , and returning the list to the cf 305 . the dte 308 decides among one or more of these operations based on current user requirements . for example , if only the top ( most important ) keywords from a set of documents are needed , then operation 1 above is utilized . if there is a need to cluster the documents returned and then find the most important ( representative ) keywords from each cluster , then operation 2 above is utilized . the local application states 309 includes information about the current user activity using one or more devices 20 or 30 ( e . g ., the user is listening to music using a dtv ). the client ui 310 provides an interface for user interaction with the system 300 . the ui 310 maps user interface functions to a small number of keys , receives user input from the selected keys and passes the input to the cf 305 in a pre - defined form . further , the ui 310 displays the results from the cf 305 when instructed by the cf 305 . an implementation of the ui 310 includes a module that receives signals from a remote control , and a web browser that overlays on a tv screen . the query execution planner ( qep ) 312 provides a plan that carries out a user request to perform a task such as a search . the correlation plan executor ( cpe ) 314 executes the plan by orchestrating components in the system 300 and correlating the results from the components to deliver better results to the user . for example , the cpe 314 performs a “ task ” by orchestrating all the components and devices required for performing the task . the correlation constructor 316 cooperates with the qep 312 to form a plan by correlating data gathered from external sources with the data gathered from the local network . the correlation constructor 316 can also form the plan automatically using the correlation . the metadata gatherer from structured sources 318 gathers metadata about local content from the internet structured data sources 320 . the internet structured data sources 320 includes data with semantics that are closely defined . examples of such sources include internet servers that host xml data enclosed by semantic - defining tags , internet database servers such as cddb , etc . the query 322 is a type of encapsulation of the information desired , and is searched for , such as on the internet . the query 322 is formed by the cf 305 from the information and metadata gathered from the local and / or external network . the search engine interface ( sei ) 324 inputs a query 322 and transmits it to one or more search engines over the internet , using a pre - defined internet communication protocol such as http . the sei 324 also receives the response to the query from said search engines , and passes the response ( i . e ., search results ) to a component or device that issued the query . the internet unstructured data sources 330 includes data or data segments with semantics that cannot be analyzed ( e . g ., free text ). internet servers that host web pages typically contain this type of data . the web pages 326 include web pages on the internet that are returned in the search results . in one example , when a query is sent to a search engine , the search engine returns a list of urls that are relevant to that query . for each relevant url , most search engines also return a small piece of text such as a snippet , from a corresponding web page . the main purpose of the snippets is to provide the user a brief overview of what the web page is about . the snippet is either from the web page itself , or taken from the meta tags of the web page . different search engines have different techniques for generating these snippets . the snippet analyzer 328 inputs the search results and a query from the cf 305 . the snippet analyzer 328 then analyzes snippets from the search results and extracts from the snippets terms that are relevant to the query . the extracted terms are provided to the cf 305 . the cf 305 orchestrates contextual query formation , contextual search and refinement by : ( a ) providing contextual information to appropriate components in the system 300 ( i . e ., one or more of the components 302 , 306 , 310 , 324 , 328 , 308 , 318 ) for query formation , query plan formation , plan execution or examining search results . ( b ) receiving a list of terms from components that retrieve related information from the internet ( i . e ., one or more of components 308 , 328 , 324 ). then , making the following decisions : ( i ) whether the terms in the list should be further refined ; ( ii ) whether any of the terms in the list carry contextual information ; ( iii ) whether and how a new query should be formed using the contextual information and the existing query ; and ( iv ) whether any of the contextual information should be used as context for a query . ( c ) if new contextual terms are found from a list of terms , then using all or some of the terms in task formation , and optionally providing the terms to the lcig 302 to store for later use . ( d ) if a new query should be formed , then constructing the query according to the decision made and executing the new query . ( e ) if some of the contextual information should be used as context for a query , then using such information according to a pre - determined format , and executing the query . ( f ) if a list of terms returned by a component needs to be further refined , then further refining the list of terms using the contextual information . as such , a ce device 20 or 30 ( fig1 ) configured based on the process 200 and the system 300 can form a query and perform a search using contextual information about a user &# 39 ; s activity , local network content , and the metadata about such content . the user is not required to be involved in this process . further , users need not be skilled in query formation to obtain relevant results such as from the internet . such a configured ce device uses contextual information to select among the relevant results returned in response to the query . as is known to those skilled in the art , the aforementioned example architectures described above , according to the present invention , can be implemented in many ways , such as program instructions for execution by a processor , as logic circuits , as an application specific integrated circuit , as firmware , etc . the present invention has been described in considerable detail with reference to certain preferred versions thereof ; however , other versions are possible . therefore , the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein .