Film giant Peter Jackson has spoken out about the "fragile state" of the industry after confirming that his much-anticipated The Hobbit is yet to gain financial backing.

Jackson, who spoke at the 40th annual Comic-Con on California the largest comic book and popular arts convention late last week, said changing technology meant fewer people watched films on the big screen.

"The film industry is in this weird state of falling box office, or so the studios feel; DVDs are down, internet piracy, and it's in a fragile state," Jackson said.

"It feels like the entire industry is playing a defensive game at the moment."

He was at the event to promote the trailer for his first big-budget science-fiction movie, District 9, filmed in South Africa.

He spoke on panel discussions, along with Titanic director James Cameron, about the future of film.

"If people want to see movies on their iPod, I can't do anything about it," Jackson said. "But iPod movies are postcards of the film experience. They can't compete with the theatrical movie experience."

He said the medium of film was "infinitely superior to any other" because of its emotional core, not its fancy dressing.

"The whole thing about the future of movies and technology is, to me, just a huge red herring, because movies are all about story and character," Jackson said.

He told the crowd of 6000 that the two-film adaptation of The Hobbit, to be directed by Guillermo del Toro and shot around Wellington, was three to four weeks away from having its first draft submitted to Warner Brothers.

He said the film was yet to receive a green light and therefore had no budget.