Ok I just tried many things.
With everything has it is, a movie with Dolby TrueHD 7.1 audio track (show in emby real one is Dolby Atmos - Dolby TrueHD). Playing through LG Emby Apps (the version released today 1.0.24) on server 126.96.36.199.
I start the moving, I see "direct streaming" with transcoding position and buffer. My Sony STR-DN1080 show "Dolby Digital 5.1(3/2)". It is connected through the Arc port (and earc on the sony).
If I disable all 3 transcoding, it now show direct play, and the sony display "Dolby Digital 5.1(3/2)".
Both of them display "HDR" on startup, but the image isn't the same.
If I check one or two configuration in any order, I always receive the message "there is no compatible stream", thus it's working when everything is checked or none are checked. But in the event that all are checked, it's transcoding.
Now, here, everything shows has Dobly Digital 5.1(3/2)" on my receiver, while it's Dolby Digital TrueHD 7.1. THat's because ARC cannot do lossless TrueHD 7.1, only earc can.
If I play from my PC directly the 4k video, which is connected directly in my sony amp through HDMI, my amp display "Dolby Atmos - Dolby TrueHD". My computer isn't able to play 4k so that's why I'm using the emby app.
Aside from having a more powerfull pc, the best case scenario for me would be to have the xbox one app do direct streaming since it can play 4k hdr/dv and dolby atmos because it's connected directly to my amp, not through arc. But for now, it's the LG TV App that is doing some transcoding that isn't needing since my TV does it anyway (has showed by the amp).
Edited by nodiaque, 21 February 2020 - 11:34 AM.