Help get (more) Dolby Atmos on Apple TV

I actually think that (mostly) Plex broke it rather than Nvidia.

But then again there were (at its peak) at least 5 different issues that surfaced on Plex on the shield. Only one of those issues ever appeared In Emby and Jellyfin.

Plex finally fixed pretty much everything on something like the 5th or 6th attempt.

Is there a way for Plex to possibly convert Atmos TrueHD 7.1 tracks to MAT with Atmos Metadata?

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Nope.

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A post was merged into an existing topic: TrueHD Atmos

Is Lossless (TrueHD) with Atmos available now? I thought that wasn’t possible due hardware limitation.

No it’s not.

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I can’t speak to what local transcoding may be occurring within Apple TV using the Infuse app. And TrueHD clearly isn’t bitstreamed to my Sonos Arc+Ones+Sub. It would, of course, to help to have a Stat for Geeks mode to tell us what is occurring between ATV+Infuse.

But, you can direct play a TrueHD file to Infuse from Jellyfin, where the video has no alternative audio tracks.

Perhaps @James can confirm whether it is converted to Dolby MAT 2.0 with or without Atmos objects.

It’s converting the TrueHD track to PCM internally. The atmos metadata is discarded.

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Nothing is ever bitstreamed on Apple TV hardware.

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So I have some questions about when Apple TV converts TrueHD to PCM. While there will be some compromises such as discarding the Atmos metadata, we are still get other benefits, right?

For example:

  1. Are we still getting a lossless audio quality, or is it something else? PCM is uncompressed so it should theoretically not downgrade the audio quality, right? There has to be a difference compared to something like a Dolby Digital Plus lossy source.

  2. If the original track was TrueHD Atmos 7.1, is it converted to PCM with a 7.1 multi-channel metadata, or is that lost with the Atmos metadata too? PCM supports up to 8 channels, right?

So the conclusion I am trying to get at is that we just lose the Atmos benefits, which mainly has to do with better surround techniques, but we still get the 8 channel setup and amazing audio quality that is more or less same to original TrueHD source, right?

Correct.

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In principle what you’re saying is correct. But, there is another caveat to consider: bandwidth.

Dolby Atmos and DTS-HD MA are lossless compressed format, and the receiver will have the role of decompressing them while PCM is raw lossless. The decompression is handle at the Infuse level. Now, HDMI has a fixed amount of bandwidth reserved for audio, so streaming a compressed format may result in higher bitrate while the raw version, it will consume more space and therefore, it may have a lower quality.

In practice we still talk about super high quality lossless, so the difference may not be that noticeable.

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The bandwidth of HDMI 2.0/2.1 is enough to transmit the unpacked sound without trimming the bitrate. Therefore, today it does not matter who exactly is engaged in unpacking these audio tracks.

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A post was split to a new topic: Box R 4K Plus

Apple TV 4K 2022 does not support Dolby Atmos Lossless and DTSX

Is there a solution for films with Atmos Lossless audio track to be played in Atmos DD+ instead of PCM 7.1 (TrueHD) and for DTSX?

Or do Atmos Lossless and DTSX films have to be obligatorily played in Dolby TrueHD/DTS-HD?

Thanks

I just gave up and using ATV as a main media player. What’s also annoying is that Firecore is loading libraries every time and it’s slow. Now I use Nvidia Shield Pro and Plex as main video player. All audio formats play perfectly. Apple really messed up by removing Passthrough.

I guess that just depends on your priorities. NVIDIA Shield will result in inaccurate colors for anyone who has Dolby Vision files in their library whereas Infuse has accurate colors but can’t passthrough object metadata of Spatial Audio formats.

Also, Apple didn’t remove Audio Passthrough… it never existed in the first place.

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Early versions of tvOS had bitstream support. It was removed in the 12 or 13 version of tvOS.

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I feel like it only supported 5.1 and there were issues. PCM worked much better.

There was. Long time ago when I used to use Apple tv for Kodi, there was working passthrough. I think it was TV OS 10. or 11. Can’t remember now. Shortly after that I switched to Coreelec media box because of that. And then Nvidia Shield Pro.

Not sure what do you mean about Dolby Vision on Shield but I have both Shield and Apple tv and both can play DV files fine. Apple tv DOES not display those better or worse. Just about the same.

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