Elemental Technologies raised $13 million in Series C financing. The start-up rapidly gained some of the largest MSOs and programmers as customers with its video processing systems based on a combination of advanced hardware and software.

At the same time, Elemental said it appointed Kevin O’Hara chairman of the board, a position until recently held by Elemental founder and CEO Sam Blackman.

O’Hara, currently CEO of Integra Telecom, was a founder of Level 3 Communications. He has been serving on Elemental’s board.

The funding round was led by Norwest Venture Partners, which was joined by previous investors General Catalyst, Voyager Capital and Steamboat Ventures. NVP’s past investments include Omneon, Polycom and Rackspace.

“Elemental’s ascendance in the IP video delivery market over the last two years has been well-documented and something we have watched closely,” said Robert Abbott, general partner at NVP. “When combined with the clear growth trajectory of the over-the-top video and TV Everywhere markets and its deep technology differentiation, we believe now is the right time to invest in Elemental.”

Elemental Technologies’ customers include Comcast, Disney and HBO.