Tarantino is not competing in this year's event, but he spoke to journalists and film critics before a 35mm screening of his hit "Pulp Fiction" on the beach on Friday night.
"The fact that most films now are not presented in 35mm means that the war is lost," said the director of the cult hit "Reservoir Dogs".
Digital formats and distribution have swept the world of cinema, largely because of cost - most of the films in Cannes are now projected that way.
But aficionados still sing the praises of the old-school film reels - in the same way that music buffs hold on to their vinyl LPs over compact discs. Fans obsess about the warmth and fineness of the 35mm grain and its ability to record the darkest of shadows and the brightest of lights.
"Digital projections, that's just television in public. And apparently the whole world is okay with television in public, but what I knew as cinema is dead," said Tarantino.
"I'm hopeful that we're going through a woozy romantic period with the ease of digital and I'm hoping that while this generation is completely hopeless, that the next generation that will come out will demand the real thing," he added.
The director known for the energy and violence of his films said digital did have some advantages.
"The good side of digital is the fact that a young filmmaker can actually now just buy a cellphone and if they have the tenacity to actually put something together ... they can actually make a movie," he said.
Before the advent of digital, the barriers to getting a film made were so great, it was like a "Mount Everest that most of us couldn't climb".
"But why an established filmmaker would shoot on digital, I have no fucking idea at all," added Tarantino.
The director said he has a "pretty terrific" collection of 35mm prints at home, and an even bigger 16mm one, "and I screen them all the time, I'm always watching movies".
"One of the nice things about my life, because I've done fairly well in cinema, it's kind of afforded me a chance to almost live an academic's life, and so my feeling is I'm studying for my professorship in the history of world cinema and the day I die is the day I graduate."
Tarantino was asked about his win of Cannes' top Palme d'Or prize in 1994 for "Pulp Fiction."
"Winning the Palme d'Or, to this day, as far as laurels are concerned, is my single absolutely, positively, greatest achievement," said Tarantino.
"Of all the trophies that I have won, it is the one that has the biggest place of honor in my house, it's the one I want another one of, maybe, someday, before they turn out the lights."
One idea currently intriguing Tarantino is turning his 2012 Western "Django Unchained", starring Jamie Foxx and Leonardo DiCaprio, into a four-part mini-series for cable, using extra unseen footage, he said.
Eighteen films are competing for the Palme d'Or in the festival's main competition this year. The prize will be awarded on Saturday.
( Source: reuters.com )