PARIS — Three portraits dominate Gilles Jacob’s homey office at Cannes Festival headquarters in Paris. Propped against walls are mounted posters of Francois Truffaut and Marlene Dietrich. Above a sofa, in a pop-art fresco, Federico Fellini, with sombrero and long coat, stands on a blue-skied Cannes beach.

Jacob, a courteous host, walks up to the painting. “When directors come here, they sit on the sofa, and I take photos. Polanski liked the painting,” he says, beaming in characteristic Jacob style with a full-faced, boyish grin.

It’s impossible to understand Cannes without understanding the elegant, enthusiastic and self-effacing Jacob. For half of the history of the world’s most prestigious festival, he’s steered Cannes’ fortunes — as delegate general starting in 1978 and president since 2000 — with dedication, diplomacy and discretion.

In a lengthy conversation, the Polanski reference is one of the few times that Jacob — who has met most of the world’s great directors — comes anywhere near name-dropping. But it is clear where his heart is, and has always been. Acting legends and hallowed auteurs don’t just populate his work environment: They shape his film landscape as well.

In film terms, Jacob came of age during World War II, when the Jacobs, like many Jewish families, left Paris for Nice. An adolescent Jacob discovered his own form of escape, catching two to three films weekly on Nice’s Avenue de la Victoire.

After the ravages of war, France found in the cinema — both local masterpieces and Hollywood — a ready relief and the possibility for the reconstruction of national culture.

“I love cinema,” Jacob professes. “Everybody educated in the ’40s and ’50s had two loves: literature and cinema.” As a student, Jacob edited a quarterly film review, Raccords. Pierre Rissient, a longtime festival aide with a keen nose for new talent, remembers picking up a copy at Paris’ Ars Una bookshop in the early ’50s. He took note of “a remarkably written and insightful essay” by Jacob, about John Huston’s first films. Back in Paris after the war, Jacob spent years working at his family factory, a subsid of the Toledo Scale Co., slipping away early to catch films.

It was an essay collection, “History of Modern Cinema,” that brought Jacob wider recognition, and a critic’s post at magazine Cinema 64. (He later reviewed for weeklies Les Nouvelles Litteraires and L’Express.) The timing of “History” was key. It was published in 1964, a few years after Truffaut’s “The 400 Blows” and Jean-Luc Godard’s “Breathless,” and as European art cinema began to fascinate the world. Both of these helmers received chapters.

It’s the great tradition of European art films and its Hollywood ’70s counterpart — movies that are more than popcorn fare — that Jacob and Cannes at large have sought to preserve and renew.

That commitment’s played out in multiple ways over the years. In the media’s eyes, adding up U.S. pic counts at the fest, Cannes-Hollywood relations have blown hot and cold. The real rub, Jacob says, was that, “In the case of world premieres, the studios were afraid of the influence of the European press on the American press.”

But U.S. directors who drank deep at the well of great European cinema — Italy’s neorealism, Bergman, France’s Nouvelle Vague — sometimes broke this impasse.

“Some great directors pressured the studios to go to Cannes,” Jacob recalls, citing Coppola and “Apocalypse Now,” the 1979 Palme d’Or winner.

Another Cannes carp is that it rolls out Riviera regulars, perennial star auteurs, whether on form or not. But that’s one of the tenets of auteur thinking: that any film, however weak, says something about a director’s overarching oeuvre.

Perhaps Jacob’s largest achievement — “a source of pride,” he confesses — has been to realize from the early ’70s that the auteur talent pool requires constant renewal.

Upon becoming Cannes’ delegate general, he immediately inaugurated a Camera d’Or prize for first-time filmmakers. Jacob also helped anoint some of the most important auteurs to have emerged in the last three decades, including Lars von Trier, the Coen brothers, Quentin Tarantino, Emir Kusturica, Hou Hsiao Hsien and Abbas Kiarostami. While not all were discovered at Cannes, their selection or prizes at the fest consolidated their careers and catapulted them into the international spotlight.

As another bolster to auteur renewal, Jacob in 1998 launched Cinefondation, a Paris-based filmmakers’ screenwriting lab, as well as Cinefondation Atelier, a networking initiative at Cannes for young directors and producers (see story, page 28).

At 77, Jacob shows no sign of slowing down. He’s writing his memoirs, “Life Will Go By Like a Dream,” which mixes personal flashbacks with memories of his life, his relationship with Cannes and the cinema world. Jacob says the book will include such things as “an interview with (Maurice) Pialat, Woody Allen, a scene from a Kubrick film.”

He’s developed a taste for filmmaking, himself, he adds. His most notable production, last year’s 33-part omnibus “To Each His Own Cinema,” commemorating Cannes’ 60th edition, raises perhaps the largest question about Cannes’ future and its current paradox. In Walter Salles’ spirited seg, two Brazilian musicians rap about Cannes outside a moldering village theater showing Truffaut’s “400 Blows.” One’s read all about Cannes on the Internet: “It’s leader’s called Gil.” The other thinks “Blows” is a porn film.

Cannes — and thus Jacob — has never been more famous. But, art film — barring star helmers — seems ever more minority fare.

Where will Cannes’ embrace of art cinema take it in the future? One answer, for Jacob and programming head Thierry Fremaux, has been for Cannes to take the developing world to its heart — sometimes, literally: Two of Jacob’s four great hopes hail from Mexico (Amat Escalante) and Sri Lanka (Vimukthi Jayasundara). This year’s Atelier invites young filmmakers to Cannes from Estonia, Somalia, Uruguay and Vietnam.

Whatever answers Cannes gives to its future, Jacob has fought hard for the festival to make them on its own terms. Negotiating broadcaster money and corporate sponsors — Canal Plus, L’Oreal, Chopard — Jacob has matched Cannes’ public funding with private-sector finance. “Little by little, we’ve wrestled independence from economic, artistic, diplomatic, professional and friendship pressures,” he says.

And, while over the last 30 years, Europe’s other large fests — Berlin, Venice — have reinvented themselves, sometimes painfully, Cannes has largely stayed its own course. It enters its 61st edition this week on what looks like an even keel.

Six days after our interview, in Paris’ august Grand Hotel, Jacob and Fremaux sit side by side to present this year’s Official Selection. Jacob announces that Cannes has to be “recentered and renewed”; Fremaux notes the beginning of “a new cycle.” But this is no desperate back-to-the-blackboard start from scratch, rather a greater focus on newer or unknown filmmakers.

When Jacob became Cannes president, speculation ran rife whether Jacob and the more unbuttoned Fremaux could really get along. Jacob’s as-yet-unseen comedy “Retour a Tullins-Fures,” a fictionalized biography of Fremaux (played by Jean-Pierre Leau) intercut with scenes from classic films, hardly suggests large tensions.

“Under him, the Official Selection became less official and more of a selection,” Fremaux says of Jacob’s programming legacy. “His routine at Cannes is totally different to 10 years ago, but he has the same fighting spirit, the same joy, and a great capacity to open his mind to discover new activities.”

Adds Rissient, “I’ve seen Gilles opening himself up and extending his vision of the role of Cannes as a festival and his personal role in leading it.”

Cannes remains the festival against which all others measure their importance. And that can be put down in no small part to the gentlemanly Jacob. Though he’s far too modest to ever say it himself.

Steven Gaydos contributed to this report.

1978: Appointed General Delegate
2000: Appointed festival President, names Thierry Fremaux Artistic Delegate.
2007: Upon Jacob’s proposal, Fremaux appointed General Delegate

“Once I accompanied Grace Kelly in her car, and she gave me her loveliest smile. Woody Allen onstage saying: `It’s because I wear glasses that people take me for an intellectual.’ And giving the Medaille des Arts et Lettres to Sharon Stone.”

“When we had to start the festival in 1983 in the new Palais: The projector lamps blew one after another, for no apparent reason.”

“Martin Scorsese’s `Goodfellas.’ I tell the story in the book I’m writing.”

Vimukthi Jayasundara, Sri Lanka (“The Forsaken Land,” Un Certain Regard selection, Camera d’Or winner, 2005)
Amat Escalante, Mexico (“Sangre,” Un Certain Regard, 2005; “The Bastards,” Un Certain Regard, 2008)
Celine Sciamma, France (“Water Lilies,” Un Certain Regard, 2007)
Antonio Campos, U.S. (“Buy It Now,” First Prize, Cinefondation, 2005; “After School,” Un Certain Regard, 2008)

The fest prexy’s list of the top 10 films of all time is ever-changing. Instead, he offers his top 10 comedies, adding,”It’s important to have a sense of humor when you help run a festival.”
“The Great Dictator,” Charles Chaplin, U.S., 1940
“The General,” Buster Keaton, U.S., 1927
“Duck Soup,” Leo McCarey, U.S., 1933
“Play Time” Jacques Tati, France, 1967
“Liberty for Us,” Rene Clair, France, 1931
“Annie Hall,” Woody Allen, U.S., 1977
“Kind Hearts and Coronets,” Robert Hamer, U.K., 1949
“La grande guerra,” Mario Monicelli, Italy, 1959
“The Meaning of Life,” Terry Jones and Terry Gilliam, U.K., 1983
“Doctor Strangelove or How I Learned to Stop Worrying and Love the Bomb,” Stanley Kubrick, U.S., 1964