DTS-HD, or as it's properly know, DTS-HD Master Audio, is a form of Digital Theatre System (DTS) audio, owned by DTS, Inc. DTS-HD supports an unlimited number of surround sound channels. It supports bitrates from DTS Digital Surround up to lossless audio and can be downmixed to 5.1CH and 2CH audio.
DTS-HD Master Audio finds its audience in home theater systems by being part of the specifications of both blue laser next generation formats. HD DVD and Blu-ray Disc have both selected DTS-HD as an optional surround sound format to be included on retail titles to provide the highest quality audio. Both DTS-HD and it's competitor, Dolby TrueHD, are the only two formats that provide compressed lossless surround sound for both blue laser formats.