I'm completely at a loss on where to ask this but I thought I'll try here.
So I decided to test out the LG C7T's inbuilt media player and found something interesting.
It can play Atmos tracks over HDMI/ARC to my Marantz SR 7011 if the video file is contained in .mp4. I used the test files from the Dolby Atmos website:
https://www.dolby.com/us/en/guide/test-tones.html
However, Atmos audio in .mkv containers do not work.
Anyone has any idea why?
Nothing to do with Kodi, but you can try converting your MKV's to MP4 with VLC media player, or a paid app like VideoRedo.
The difference here is Dolby TrueHD Atmos vs Dolby Digital Plus Atmos. The test tones have Dolby Digital Plus Atmos, whereas the ones in MKV may have Dolby TrueHD. There is a speculation that LG may enable eARC on these OLEDs. Only time will tell...
(2017-11-20, 04:02)wesk05 Wrote: [ -> ]The difference here is Dolby TrueHD Atmos vs Dolby Digital Plus Atmos. The test tones have Dolby Digital Plus Atmos, whereas the ones in MKV may have Dolby TrueHD.
Is there some way to find out what the Dolby Test Tones are encoded in?
(2017-11-20, 04:09)wesk05 Wrote: [ -> ] (2017-11-20, 04:05)Enchilada Wrote: [ -> ] Is there some way to find out what the Dolby Test Tones are encoded in?
The are Dolby Digital Plus Atmos: https://pastebin.com/kgy7B5iL
You can use MediaInfo app to check it.
Hah! I just downloaded the same app to check. Looks like you're even faster.
So just to clarify, the issue most media players have is Dolby TrueHD Atmos as opposed to Dolby Digital Plus Atmos?
(2017-11-20, 04:16)Enchilada Wrote: [ -> ]So just to clarify, the issue most media players have is Dolby TrueHD Atmos as opposed to Dolby Digital Plus Atmos?
Sort of. If the device doesn't support HD audio passthrough, you are going to have issues with Dolby TrueHD Atmos. In your case, your LG TV doesn't support Dolby TrueHD over HDMI ARC. eARC that comes with HDMI 2.1 will support HD audio passthrough. There is a rumor that LG may enable eARC for 2017 OLEDs.
(2017-11-20, 04:40)wesk05 Wrote: [ -> ] (2017-11-20, 04:16)Enchilada Wrote: [ -> ]So just to clarify, the issue most media players have is Dolby TrueHD Atmos as opposed to Dolby Digital Plus Atmos?
Sort of. If the device doesn't support HD audio passthrough, you are going to have issues with Dolby TrueHD Atmos. In your case, your LG TV doesn't support Dolby TrueHD over HDMI ARC. eARC that comes with HDMI 2.1 will support HD audio passthrough. There is a rumor that LG may enable eARC for 2017 OLEDs.
I see.
So the only way to get Dolby TrueHD Atmos output to my AVR/Speakers is via passthrough-enabled media players such as nVidia Shield, AMLogic Boxes, etc.
This also means that the Netflix App on my LG C7T will only pass Dolby Digital Plus Atmos to my AVR/Speakers when playing Atmos-enabled Netflix videos. Yes?
It's unlikely that streaming sources are going to be using Dolby True HD + Almos tracks. The bitrates required just for the audio component are higher than Netflix use for 1080p HD video AND audio... (Dolby True HD audio is going to be in the 3-6Mbs range for 5.1-7.1 - Dolby Digital Plus will be <448kbs for streaming services - possibly a lot lower?)
I'd expect most streaming sources using Atmos to be using Dolby Digital Plus with Atmos - NOT True HD.
(eARC does have a place - supporting passthrough from Blu-ray sources etc. and also for local media playback of content that may not be lossy compressed)
Thanks for the lesson guys.
It's quite interesting. Makes me wonder how streaming services decide how to apportion bandwidth to audio/video tracks.
(2017-11-20, 13:49)Enchilada Wrote: [ -> ]Thanks for the lesson guys.
It's quite interesting. Makes me wonder how streaming services decide how to apportion bandwidth to audio/video tracks.
I think the reality is that relatively few golden-eared people can really tell the difference between DTS HD MA 5.1 and 1.5Mbs DTS 5.1... (Even broadcast 5.1 masters are often 2.3Mbs Dolby E...)
AIUI The major reason to move to DD+ from DD was to increase from 5.1 to 7.1 - and exploit the newer compression algorithms that let you drop bitrates further for a given perceived quality...