SAN JOSE, Calif. — TiVo Inc. is introducing music to its mix of entertainment services, offering owners of the company's digital video recorders access through their TVs to RealNetworks Inc.'s Rhapsody music service.

The new feature, being announced today, means TiVo subscribers with broadband-connected set-top boxes will be able to listen to music streamed over the Internet from Rhapsody's service, which has a catalog of more than 4 million songs.

Tivo and RealNetworks view their partnership as a cross-marketing way to boost their subscriber bases.

The deal also marks the latest in a string of features TiVo has added to promote itself as a premium service. TiVo has teamed with Amazon.com for movie downloads and with Yahoo Inc. for photo-sharing. It also offers direct access to some online content and lets users share home movies with other TiVo users.

Whether users access it through TiVo, a PC or portable gadgets, the Rhapsody service will cost $12.99 per month on top of the $12.95 or more TiVo regularly charges.

Rhapsody is considered one of the leading providers, along with Napster Inc., of subscription music. It's not as popular as a la carte download services such as Apple Inc.'s iTunes Store.

TiVo says it will roll out the Rhapsody feature in stages, with priority for current customers who sign up.

In its fiscal second quarter, TiVo saw its number of subscribers drop to 4.2 million from 4.4 million a year ago.

RealNetworks, a digital media services company, does not disclose specific subscriber totals for Rhapsody. But it had about 2.7 million subscribers, up from 1.7 million, including all its music-related services, in its fiscal second quarter.

TiVo, a pioneer of DVRs that let users pause live television, zip past commercials and record programs without tapes or CDs, is competing against often cheaper offerings from cable and satellite TV operators.

It isn't alone in trying to provide one-stop shopping for digital entertainment.

Larger rivals, such as Apple and Microsoft Corp., are on a similar track, for instance, with Windows media centers, the Xbox 360 game console and the Apple TV set-top box.