Warner Bros. will release the next two "Harry Potter" films in 3D, a move underscoring the post-"Avatar" rush for extra-dimensional box office returns.

Studio executives around town have been scrutinizing film slates for opportunities to expand forays into 3D releasing. Warners has been testing footage from its upcoming "Clash of the Titans" -- converted into 3D by an outside vendor -- and the tests have gone so well that the studio has decided to release not only "Titans" but also the two-part "Harry Potter and the Deathly Hallows" in 3D.

Warners refused to confirm the decisions Tuesday, but an announcement on "Titans" -- a co-production with studio-based producer Legendary Pictures -- is expected by week's end. Official word on the "Potter" pics also is awaited.

Conversion expenses have been coming down, so each film will cost just $5 million to change into 3D. Warners also will absorb an additional $5 million expense per picture to pay for 3D glasses for exhibitors handling the movies.

In a related move, Warners will push back the release of "Titans" one week to April 2. "Deathly Hallows: Part I" is set to unspool November 19, and "Part II" is slotted for July 15, 2011.

As for the impact on box office prospects for the final two "Potter" sequels, consider the more imminent situation with "Titans."

A remake of a 1981 film starring Laurence Olivier, "Titans" previously might have been expected to fetch no more than $200 million domestically, and even that was an aggressive projection. Released in 3D, Warners figures to reap well north of $200 million, with 2007's $211 million domestic grosser "300" considered a beatable benchmark.

"Titans" in 3D also is considered a safe bet to best the $245 million in foreign coin that Warners fetched with "300."

The "Titans" move is not without risk. The installed base of 3D movie screens has been growing rapidly, but it's not sufficient to release the film entirely in 3D.

That should be less of a concern by the time the next "Potter" hits multiplexes. But execs also are quietly confident of getting enough 3D playdates for "Titans."

"I would not think it would be an issue to establish ourselves in the 3D marketplace with 'Titans,'" a studio insider said. "By sliding it back a week, we should at least have enough screens in the major markets."

Warners should secure upward of 1,000 playdates for "Titans," which will unspool a week after Paramount bows DreamWorks Animation's spring tentpole "How to Train Your Dragon."

The "Titans" move might spur further reshuffling in the spring release calendar, as its new date makes for a fifth wide opener set for Easter weekend, which historically is a solid boxoffice session but hardly one to support that many big pics.

Other wide openers set for April 2 include Fox's "Diary of a Wimpy Kid," a likely PG-rated film adapted from a book series popular with middle-schoolers; Disney's PG-rated Miley Cyrus starrer "The Last Song," adapted from a Nicholas Sparks novel; Universal's futuristic action thriller "Repo Men," starring Jude Law and Forest Whitaker; and Lionsgate's latest Tyler Perry pic, "Why Did I Get Married Too?"

Meantime, the move of "Potter" into the extra dimension could prompt other high-profile moves. Could a 3D James Bond loom?

Warners' decision with its "Potter" franchise is likely at least to prompt 3D discussions between MGM and 007 producers. But unlike Warners' incremental move with the "Potter" franchise -- going with full-on 3D only after an initial foray into partial Imax 3D -- Lion execs would be starting at square one in talks on Bond.

Still, there is the siren call of those extra-dimensional dollars -- and other 3D currencies. In addition to lusting after "Avatar"-like boxoffice, industry execs have taken note of how well 3D pics play overseas.

Warners 3D horror pic "The Final Destination" overperformed internationally this summer, and Sony's 2D "Zombieland" did less than one-fourth as well overseas as domestically a few months later.

Perhaps by no coincidence, Sony might send "Spider-Man" into the third dimension with the webslinger's next pic.