It seems that there is a lot of confusion in “Dolby/DTS Passthrough Issues” about lossy and lossless codecs from DTS that I thought there should be its own thread with an explanation.
DTS-HD and DTS-HD MA (DTS-HD Master Audio) are two different codecs. DTS-HD is lossy, supports up to 5.1 channels, and has a sampling rate of up to 96kHz. DTS-HD MA, on the other hand, is lossless, supports up to 7.1 channels, and has a sampling rate of up to 192kHz (see DTS pdf below).
A majority of Blu-ray movies are DTS-HD MA, so you will only get the lossy DTS 5.1 core coming out of the Apple TV until Infuse actually supports the lossless wrapper. James has stated that they are working on lossless codecs, but it is currently not supported. This includes lossless codes from both DTS and Dolby (TrueHD) and eventually we may see the new DTS:X and Dolby Atmos codecs supported too.
So stop complaining that DTS-HD isn’t working, when it is probably DTS-HD MA that isn’t working. If you don’t know what your source is, use an app like MediaInfo to tell you. I do think that Infuse should put a superscript on “DTS-HD” and say “DTS-HD MA is not currently supported” to prevent more confusion. Also I request to users that in other threads, try to be more specific about the formats and don’t just say “HD audio” because that isn’t synonymous with lossless.
or pdf “DTS-HD® and DTS-HD Master Audio™: Enabling HD Audio Across an Evolving Media Delivery Landscape” under “White Papers” from http://www.dts.com/resources/resource-center.aspx