Crowds crammed to see the stars walk the red carpet, champagne flowed, fireworks filled the sky and screenings were packed, yet the Cannes film festival hit halfway on Monday lacking one key ingredient -- buzz.

The world's largest annual cinema showcase opened on May 12 and closes on May 23, when one of 19 movies in the main competition will be named winner of the coveted Palme d'Or.

As important to a successful festival are the hundreds of films shown out of competition and in the giant marketplace where producers and distributors wheel and deal.

With the majority of competition films yet to screen, the early front runner for the top prize is British director Mike Leigh, whose wry family drama "Another Year" was widely praised. He won the main award with "Secrets and Lies" in 1996.

Also popular was Mexican filmmaker Alejandro Gonzalez Inarritu's "Biutiful," a moving portrayal of a dying father played by Javier Bardem, and a low-budget drama from Chad, "A Screaming Man," set against conflict in the African country.

But most movies eligible for awards have disappointed so far, and what stars there have been in the French Riviera resort have generally failed to shine either on-screen or off.

"I think we're lacking people who know how to play to the media, how to play it up and how to charm on the red carpet and in interviews," said Variety critic Jay Weissberg.

"At the Cannes festival in particular, it needs that interplay between the star and the press and public, and we haven't really had that yet."

There is still time, with major celebrities including Mick Jagger and Sean Penn expected to arrive along with an influx of party goers from nearby Monaco, venue of Sunday's Grand Prix.

"It's been fairly quiet so far, but after Monaco, when all the yachts come, it should go 'boom'," said one event organizer.

CROWE, BLANCHETT, DOUGLAS IN TOWN

Hollywood was in town in the form of Ridley Scott's "Robin Hood" starring Russell Crowe and Cate Blanchett, and Woody Allen brought "You Will Meet a Tall Dark Stranger" to the festival held on the palm-lined waterfront.

Most topical, and giving Cannes a brief shot in the arm, was "Wall Street: Money Never Sleeps," Oliver Stone's slick follow-up to his 1987 hit "Wall Street" with Michael Douglas back as the ruthless corporate raider Gordon Gekko.

None was a critical hit, although a muted reception in Cannes need not dent their box office prospects.

Weighing on the mood here is uncertainty over the strength of the global economic recovery, which has hit financing and could further squeeze the market for independent, low- to medium-sized films from the United States and elsewhere.

"Economics have made a disparity between studio movies, most of which are at $70 million or more (to make), that have advertising and marketing budgets of $30-40 million or more, and your independent pictures which are under $12-15 million," Oscar winner Douglas said in Cannes.

"It's a bad situation right now, it's a huge disparity. It's not a good sign for the future."

His concerns appeared to be borne out in Cannes, where there is only one U.S. entry in competition, Doug Liman's "Fair Game" based on the story of outed CIA agent Valerie Plame and her husband starring Naomi Watts and Penn.

Hollywood movies tend to feature out of competition, and use Cannes as a global media platform due to the presence of thousands of reporters from all over the world.

Not everyone was downbeat, however, seeing resilience in the movie industry during tough economic times and eyeing opportunities to tap the booming 3D market.