YouTube has launched a public beta of its Video Identification tool designed to prevent copyrighted material appearing on its site.

The public launch follows several months of development and a private test with nine media companies.

David King, product manager at YouTube, wrote in the company's official blog: "Video Identification is the next step in a long list of content policies and tools for copyright owners to more easily identify their content and manage how it is made available on YouTube."

King claimed that the system beings together several new and existing initiatives, such as the repeat-infringer policy which has been in place since the site's launch.

This policy terminates the accounts of repeat infringers based on notices under the Digital Millennium Copyright Act, and provides a unique code for every video removed for copyright infringement.

YouTube has also imposed a 10-minute limit on the length of content uploaded to the site in an effort to prevent the uploading of TV shows and feature films.

Content owners are now provided with an electronic notification and takedown tool to help them identify their material and request YouTube to take it down.

"Like many of these other policies and tools, Video Identification goes above and beyond our legal responsibilities," wrote King.

"It will help copyright holders to identify their works on YouTube and choose whether to block, promote or monetise their videos if a copyright holder chooses to license their content to appear on the site."

YouTube has received hundreds of thousands of takedown requests from content providers and royalty groups since last year.

Viacom requested the takedown of 100,000 videos in February which evolved into a $1bn lawsuit filed in March.

YouTube has long been accused of dragging its heels in creating an effective filtering system to automatically identify and remove copyrighted material.

YouTube attorney Philip S. Beck told a New York court in July that the system would be in place "hopefully in September".

Glenn Brown, a partner development manager at YouTube, said: "We expect to hit unforeseen bumps and bottlenecks as we refine, improve and scale the system to meet everyone's needs.

"We have worked with [parent company] Google to develop one-of-a-kind technology that can recognise videos based on a variety of factors. Video Identification is brand-new cutting-edge stuff."