https://forum.kodi.tv/showthread.php?ti ... pid2547074
"When TrueHD was first defined the specification included the ability to add extensions to the TrueHD audio stream, these extensions have been unused until now. When Dolby came to define Atmos, they made use of these TrueHD extensions so an Atmos audio stream is simply a TrueHD stream + extensions, thus any device that supports TrueHD can pass an Atmos stream as it doesn't need to know what is inside those extensions, it simply see's it as TrueHD stream and passes it through as is."
roblrobl wrote:Hi Mike and Others,
Does something still need to be done within MakeMKV to allow or pass through Dolby Atmos audio? Here's what I see:
Thanks for any help!
- I'm using the Star Trek, Into Darkness UHD/4k disk. IT has HDR (hdr10?) and Dolby Atmos.
- I perform a full disk backup (57.1GB) and then create a single .mkv file in it with everything selected (52.1GB). Any idea on why the .mkv is smaller?
- When I open the disk backup with MakeMKV, the best audio shown is TrueHD Surround 7.1 English. When I play the .mkv file using roku/plex on my main TV/amp, the amp agrees. It's "Dolby+ 7.1 surround" or 7.2.0 and not 7.2.4. The ceiling speakers are not firing.
- Another poster claimed Dolby Atmos was perhaps mislabeled at the 7.1 stream. It doesn't seem this way to me. From what I understand, Atmos and DTS:X are both object based methods, like PC audio, where various streams have positional information, and then the stereo mixes them all to the appropriate speakers. This is quite different than the 1 speaker = 1 audio stream approach.
- Also, for the Video steam showing up as MpegH, is there any way we can get more definition on this in a future version of MakeMKV? Perhaps something that shows if it is non-hdr, hrd10, dolby vision, etc. It seems that 4k bluray players are able disregard the hdr info, and some of our PC tools don't understand them yet. Would it be possible to see them as different video streams? (such as 4k non-hdr, vs 4k hdr10?) Or an option to strip out the HDR metadata?