Jon Johansen, also known as DVD Jon, posted details about the tool on his blog on Wednesday. Johansen is also known for such hacks as and .
By removing the encoding around NSC files that store data, Johansen is able to allow open-source video media players and streaming services to tap into multicast streams, said Derk-Jan Hartman, a developer with VideoLAN, a nonprofit open-source video media player organization. Hartman and another VideoLAN member asked Johansen to come to their assistance, Hartman said.
"VideoLAN members need to multicast video, but the Windows Media Player creates NSC files that contain encoded text," Hartman said. "You need that information in order to connect to the video stream."
As a result, VideoLAN members asked Johansen if he could reverse-engineer the code, which he did earlier this week and posted the tool to his site.
Multicasting video streams let people efficiently transport large amounts of data with less load on the network, Hartman said. Heavy users of this technology include researchers and university networks, and, to a lesser degree, companies and video content distributors, he said.
Microsoft said that while Johansen's tool will remove the encoding around NSC files, it will not reveal the content of the encrypted media.
"This tool will not provide access to that content. It will not circumvent Windows Media's" digital-rights management, said Marcus Matthias, a product manager for Microsoft's Windows Digital Media division.
Nonetheless, members of VideoLAN are happy to see the removal of encoding around NSC files, Hartman said. VideoLAN members and other non-Windows-based media players will be able to get access to information such as the address of the stream server, he added.
Hartman's organization plans to soon have the capability to support and connect its open-source media player, VideoLAN Client, to multicasts from Windows Media Players. He said that may occur in the next week or so.