DVDs use compressed audio formats such as Dolby Digital and DTS for multichannel sound. NDI carries video, multichannel uncompressed audio and metadata. Stereo and multichannel surround (5.1) are both supported. Many trailers are mixed in Dolby Digital or any other multichannel sound mix. The selected source can be mixed to mono, stereo or any other multichannel format. Omnichannel retailing is an expansion of multichannel retailing. It is designed for efficient rendering of multichannel three-dimensional positional audio. The advent of multichannel digital sound in the 1990s obviated these very expensive prints. Network Ten also showed races on its digital sports multichannel, ONE. They are also broadcast in an omnibus edition each Sunday on Seven's digital multichannel 7Two. It is monaural and not a multichannel codec. Programming from the network also airs free-to-air on Nine Network's digital multichannel 9Life. Extensions such as Multichannel MP and Multichannel OMP allow one to process multicomponent signals. Bold is an Australian free-to-air digital television multichannel owned by Network 10. Since moving to digital multichannel Eleven, "Neighbours" has traditionally rated between 250,000 and 350,000 viewers.