SAN FRANCISCO — Internet powerhouse Yahoo Inc. is setting out to build a vast online library of copyrighted books that pleases publishers — something rival Google Inc. hasn't been able to achieve.

The Open Content Alliance, a project that Yahoo is backing with several other partners, plans to provide digital versions of books, academic papers, video and audio. Much of the material will consist of copyrighted material voluntarily submitted by publishers and authors, said David Mandelbrot, Yahoo's vice president of search content.

Other participants in the alliance announced today include Adobe Systems Inc., Hewlett-Packard Co., the Internet Archive, O'Reilly Media Inc., the University of California and the University of Toronto.

Although Yahoo will power the search engine located at www.opencontentalliance.org, all the content will be made available so it can be indexed by all the other major search engines, including Google's.

By joining the project, Sunnyvale, Calif.-based Yahoo is hoping to upstage Google, which has a one-year head start on scanning and indexing books so more literature and academic research can be accessed from anywhere in the world with an Internet connection.

"My feeling is we are doing something new here," Mandelbrot said. "We are building a collaborative effort that will make a great deal of copyrighted material available in a way that's acceptable to the creators. That is novel."

The alliance won't include any copyrighted material unless it receives the explicit permission of a publisher or author. That restriction means the alliance is bound to be missing much of the material available in brick-and-mortar libraries.

In an effort to be as comprehensive as possible, Google plans to index millions of copyrighted books from three major university libraries — Harvard, Stanford and Michigan — unless the copyright holder notifies the company by Nov. 1 about which volumes should be excluded from the search engine index.

Google's "so-called" opt out provision has outraged many publishers, who contend the company is flouting long-established copyright laws. The Author's Guild Inc., which represents about 8,000 writers, sued Google for copyright infringement last month. Google maintains its scanning represents "fair use" allowed under the law because it only allows Web surfers to view excerpts from copyrighted books.

Some of the most strident critics of Google's library project are endorsing the Open Content Alliance, or OCA.

Patricia Schroeder, president for the Association of American Publishers, described the alliance's approach as "very encouraging."

Sally Morris, chief executive for the Association of Learned and Professional Society Publishers, said she hopes Google follows the alliance's example. "The OCA's model of allowing rights holders to control which of their works are opened up . . . and where they are hosted may encourage others to do so."

Google also applauded the Yahoo-backed alliance. "We welcome efforts to make information accessible to the world."