NEW YORK — In the biggest clash yet between old and new video media, Viacom yesterday filed a $1 billion copyright infringement lawsuit against Google's YouTube.

Viacom says that the Web site — which Google bought last year for $1.65 billion — has shown "brazen disregard" for a demand that it stop showing user-posted video from Viacom cable shows including "The Daily Show with Jon Stewart "and "The Colbert Report" and movies such as "An Inconvenient Truth."

Viacom wants monetary damages for past abuses, which it alleges include 160,000 unauthorized clips viewed 1.5 billion times.

The suit also asks the U.S. District Court here for an injunction to bar YouTube from showing additional Viacom clips without its approval.

"The attitude of Google and YouTube has been to take people's content and ask questions later," Viacom CEO Philippe Dauman says. "That's just not appropriate for anyone to do. And it's not appropriate for one of the largest companies in the world to behave that way."

A YouTube statement said it believes the court will find it "has respected the legal rights of copyright holders" and added it will not "let this suit become a distraction."

At issue is whether YouTube is covered by the so-called safe harbor provisions of the Digital Millennium Copyright Act. It protects Web sites such as message boards from charges of copyright infringement when users inappropriately post someone else's work. But a site loses that protection if it directly profits from the unauthorized content, or doesn't promptly remove it when notified about it.

Viacom says that comedy and music clips from its channels have become "the cornerstone" of YouTube's business plan, "enabling it to gain a commanding market share, earn significant revenues, and increase its enterprise value."

Dauman adds that last month, when YouTube took down thousands of clips at Viacom request, "the traffic to our own sites for people who want to find 'Jon Stewart' increased significantly, and we're able to monetize that."

Dauman says that it's virtually impossible for outsiders to monitor the fast-changing site, but that YouTube can. "They are currently screening the content for pornography, for hate speech."

It's hard to predict who might prevail in court, because the definition of the "safe harbor" standards "has not been litigated," says Mel Avanzado, a lawyer for Jeffer Mangels Butler & Marmaro who has worked for Viacom.

And it still may not be, says David Gurwin of Buchanan Ingersoll & Rooney. "They'll probably end up coming to a settlement. This kind of litigation is very expensive. It may be a hardball negotiation tactic."