Google Inc. on Tuesday launched a TV video-search service that broadens the company's strategy of expanding search to information on and off the web, and takes it into a market where more advanced services have been available for years.

The Google Video service, released in beta, searches the closed captioning content of television programs to return still photos and a text excerpt at the point where the search phrase was spoken. Transcripts are available, but not video clips.

Hours before Google unveiled its "early-stage release," rival Yahoo Inc. launched a video search link on its homepage. The Yahoo service searches and returns actual video clips for playback, but does not offer transcripts.

Google Video is the second major announcement in the Mountain View, Calif., search giant's goal to expand its search capabilities beyond information found on the web. The company in December announced that it was digitally scanning collections of books and documents in Harvard, Stanford, the University of Michigan, the University of Oxford and The New York Public Library, making the information searchable online.

"(Video search) is very much in keeping with their broader mission of making all information, whether it's on or off the Internet, searchable," Mark Mahaney, financial analyst for American Technology Research, said.

Google's recent offerings reflect a business strategy that's more focused on search than major rivals Microsoft Corp. and Yahoo, which include search as part of their news, entertainment and shopping web portals, analysts say. Google derives the majority of its revenues from ad links, which are displayed separately from general search results.

The capabilities of Google Video, however, do not match those of video search services currently available on the web, analyst Gary Price with SearchEngineWatch.com said. Examples of TV video search services include Blinkx.tv, SpeechBot from Hewlett-Packard Co., which uses speech-recognition in its search; and ShadowTV Inc., which offers a paid business service.

"Google's is an interesting launch, but others have been doing audio and video search since the late 90s," Price said.

Nevertheless, Google's status as the leading search engine on the web, as well as its powerful marketing machine, makes its new offering turn heads, even if the service isn't new.

"When they release a product, it makes everyone's mouth drop," Price said. "They're brilliant marketers."

Google, however, has just started in the video search market, and its size makes it an immediate player.

"Who knows what Google is going to roll out in the next couple of months," Price said.

For now, Google Video is meant to attract feedback from users, Google product manager John Piscitello said. Video clips will eventually be available, but Google isn't saying when.

In the meantime, the service's preview page will display up to five still video images and five short text segments from TV programs. For individual shows, users can find out when the program will air next, and search for specific words within the program.

Program details, such as channel, date and time, can also be displayed according to zip code.

Google, for now, is indexing information it's gathering directly from TV broadcasts over satellite, Piscitello said. The company is also indexing content made available through partnerships with PBS, the National Basketball Association, Fox News and C-SPAN.