Transcode TrueHD Atmos to DD+ Atmos?

[qazwsx16 0]

So I have an interesting problem. I'm in the process of setting up my first complete home theater with a C8 as my TV was reading up on the limitations associated with ARC. I plan on using one of LG's internal Emby app.

 

The system I'm setting up is a 5.1.2 system and I was hoping that I could stream lossless audio by connecting my receiver to my C8 through the ARC connection, but I was reading that only eARC is cable of TrueHD. 

 

A quick diagram of my connections: LG C8 (Internal Emby App) -> AVR -> Speakers

 

As an example, my Avengers Infinity War file has the following for audio (which looks like no DD+ [E_AC-3]):

• TrueHD: 5174 kbps | 8 channel
• A_AC-3: 640 kbps | 6 channel
• A_AC-3: 192 kbps | 2 channel

 

I definitely want to retain the atmos channels since that's why I got the additional speakers. From my understanding, since the TrueHD can't transfer to my AVR, it would default to the A_AC-3 audio, which would not contain the atmos components (correct me if I'm wrong).

 

So my question is, would it be possible to force my Emby server to transcode the TrueHD with atmos to DD+ with atmos? And if so, is this a fairly hardware intensive transcode?

 

Let me know if I can clarify anything or if I said anything wrong!

~Q

[qazwsx16 0]

One thing I did want to clarify was that I can't send just the video from my AVR to the TV since my AVR does not support HDR passthrough (Onkyo TX NR-737).

[Jdiesel 1284]

I don't believe TrueHD to DD+ with Atmos conversation is possible, at least I have never heard of it being done before.

[samuelqwe 316]

Unfortunately, that isn’t possible at the moment as there is currently no open source software (that I’m aware of) that can decode Atmos metadata in order to retain it while converting TrueHD to DD+. Only Dolby’s own proprietary tools would be capable of such conversion.

[qazwsx16 0]

I don't believe TrueHD to DD+ with Atmos conversation is possible, at least I have never heard of it being done before.

 

 

Unfortunately, that isn’t possible at the moment as there is currently no open source software (that I’m aware of) that can decode Atmos metadata in order to retain it while converting TrueHD to DD+. Only Dolby’s own proprietary tools would be capable of such conversion.

 

Ah that is unfortunate! I've been planning this project for months and just the last few pieces the other day. Didn't even consider restrictions from the TV. Do you know if we're able to transcode the audio on our own even if Emby can't? I know you mentioned that it was Dolby's own tool, so I'm assuming now.  

[samuelqwe 316]

Do you know if we're able to transcode the audio on our own even if Emby can't? I know you mentioned that it was Dolby's own tool, so I'm assuming now.

Neither Emby or anyone else (except Dolby) is capable of doing the conversion as no generally accessible tool exists to do this. Only Dolby would be able to do it currently, but their tools are not available to the general public.

[qazwsx16 0]

Neither Emby or anyone else (except Dolby) is capable of doing the conversion as no generally accessible tool exists to do this. Only Dolby would be able to do it currently, but their tools are not available to the general public.

 

Thank you for the quick clarification! I think my plan now (and only solution) is to sell my current AVR and find one that supports HDR/Dolby Vision passthrough and connect my Nvidia Shield (Emby Server) directly to it.

Edited February 20, 2020 by qazwsx16

[otarie 2]

I dont know if it helps now that's its been some months, but if I sent a truhd atmos signal via hdmi directly from my shield tv (emby for kodi) into my c9, it sends the audio via arc to my "old" onkyo and i get a dd+ signal with atmos

[qazwsx10 6]

3 hours ago, otarie said:

I dont know if it helps now that's its been some months, but if I sent a truhd atmos signal via hdmi directly from my shield tv (emby for kodi) into my c9, it sends the audio via arc to my "old" onkyo and i get a dd+ signal with atmos

Interesting! Is there any transcoding that occurs?

[otarie 2]

Not that I'm aware of True HD Atmos goes in and DD+ Atmos. I was suspecting it might be the core track of the true hd stream.