SAN FRANCISCO — Pink Visual has taken a long-running online porn piracy battle to court, asking a US judge to stop “tube sites” from playing dirty when it comes to copyrighted digital videos.

A lawsuit filed in US district court by Pink Visual copyright holding company Ventura Content accuses a pair of Canadian companies of streaming its videos at a “pornhub” network of websites.

“Many have drawn parallels between this case and the music industry’s fight against digital piracy,” Pink Visual president Allison Vivas told AFP on Tuesday.

“Whether or not those comparisons are apt, we believe this case could set much needed precedent that will benefit the adult industry as a whole.”

While porn makers have been complaining about “the tube site business model” for years, this is the first lawsuit aimed at the underlying copyright issues, according to Vivas.

Tube sites allow people to upload and share videos for free.

“Like other notorious infringing websites before them such as Napster, Grokster and Kazaa… these tube sites threaten not just Ventura but the entire adult entertainment industry,” attorney Gianni Servodidio said in the suit.

Pink Visual has been “overwhelmed with support” from members of the industry, according to Vivas.

The lawsuit charges that pornhub websites violate US copyright law by copying, displaying and distributing Ventura videos “tens of millions of times.”

Terms of use posted at the websites warn users that they must have the rights to material they post.

Ventura has hired the Jenner and Block law firm that successfully represented copyright holders in legal cases against Grokster, Torrentspy and Usenet.com.

“We are extremely confident in the legal theory and supporting arguments that have been constructed by our legal team, and we believe our case is very strong,” said Vivas.

Ventura is seeking cash damages along with a court order barring the websites from being involved with its copyrighted material.