Help get (more) Dolby Atmos on Apple TV

It’s not about bitstream or PCM. It’s just a matter of what your receiver supports. By itself, a bitstream is just a sound stream that can contain anything. what exactly is the receiver’s task. Apple TV 4K and Infuse have nothing to do with it. And since you had only 5.1 channel audio in the bitstream format many years ago, it only means that at that time you had a 5.1 channel audio system, nothing more.

No, I’ve had a 7.1 system long before Apple TV 4K even existed and have enjoyed bitstream audio with my blu-ray player. Regardless, the Apple TV doesn’t support it and I use my player for Atmos, but infuse for everything else :slightly_smiling_face:

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The Shield’s Dolby Vision color accuracy is fundamentally broken and appears to be unfixable given NVIDIA has known about this issue for years. Here are images demonstrating this.

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Sorry but that some kind of joke. I use ATV and Shield Pro side by side since 2020, upgrading ATV with every new version and never ever saw any Dolby Vision problem on Shield Pro. Just for you, I shot video on my iPhone 13 Pro Max, showing Dolby Vision demo file playing first in Infuse ATV and then Switching to Plex on Shield Pro. As you can see, there is ZERO difference in picture quality.
Here’s download link:

It’s pretty well known issue with Profile 7 and Profile 8 content.

Profile 5 doesn’t have the issue.

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In fact, Nvidia Shield had a problem with colors. One of the owners of the Shield was able to prove this to Nvidia tech support and literally 4 months ago this problem was solved.

That’s not the same issue with Dolby Vision Profile 7 and Profile 8 content.

This issue is still an outstanding issue that likely will never be fixed.

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AFAIK the only outstanding bug is slightly elevated reds in some DV content.

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Maybe it’s TV problem? Because I honestly don’t remember any DV picture problems. I use Sony XH92 75" TV. Both NVIDIA Shield and ATV are connected to Denon 4500 AVR.

If you know about some Blu-ray rips I could test it, let me know and I’ll be more than happy to compare the playback again.

It happens with every TV and every Dolby Vision Blu-ray backup from all Shield models.

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Well, I don’t see it. Is it because the signal is going through AVR maybe?

The AVR can’t affect it. It’s a decoding error on the Shield itself.
With that said, you should probably just enjoy your Shield and not worry about the color error if it’s not bothering you :slight_smile:
…as long as you don’t have a professional requirement for color accuracy.

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Words to live by!

If it ain’t broke, don’t fix it.

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I will. And I’ll keep closer eye on it now. And once I spot something weird, I’ll let you know. :slight_smile:

Fascinating thread. What exactly is Infuse doing with AC3/Atmos content such my Denon reports “Atmos”?

Or equivalently what is Plex not doing such that my Denon reports MCH IN?

Is MCH IN an LPCM stream with Atmos stripped out? Or could it be Dolby MAT with both AC3 and Atmos encoded? Would the Denon report “Atmos” or MCH IN for the latter?

Infuse will do lossy Atmos but not True-HD Atmos. So I guess that’s when you see Atmos triggering.

Plex converts all HD-Audio to Multi Channel FLAC on the Apple TV.

(Just as a side note Plex on the ATV hilariously converts all FLAC music to AAC)

I understand the TrueHD issue. I guess I’m confused with these statements that I’ve read in this thread:

  • tvOS does not provide developer access to bitstream or Dolby MAT 2.0.
  • This thread petitions Apple to provide both as EAC3/Atmos passthrough to the AVR is only available to HLS (HTTP Live Services) streaming services like Amazon, Netflix, etc.

So that begs the question for me how Infuse is able to light up “Atmos” on my Denon AVR playing an MP4 file (with an EAC3/Atmos audio track) served up by a local server. If Infuse isn’t allowed to passthrough (due to ATV limitations), how is the audio being passed through? Or is Infuse re-encoding in Dolby MAT 2.0?

Apple supports lossy atmos with Dolby digital. It doesn’t matter if it’s streaming or local. Apple probably converts it to Dolby MAT but the method doesn’t really matter.

Atmos that works on the apple platforms: Lossy atmos with Dolby digital (handled by apple).

Atmos that doesn’t work: Lossless atmos with TrueHD (infuse has licensed codecs that decode the TrueHD core track and converts it to PCM)

This petition is to provide expanded audio options through proper pass through bitstream.

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This is just a wild guess, but I’m guessing that Infuse has a Dolby MAT license and can re-encode to Dolby MAT in its player? The only reason i’m hypothesizing this is because

  • I’ve seen positive confirmation that the EAC3/Atmos from Infuse is sent over HDMI as Dolby MAT.
  • Over at the plex boards, they are mouths-agape at why the Plex team won’t do the same thing. They are really placing a premium on the AVR reporting “Atmos” instead of “M In”.

edit/disclaimer: I’m a happy Infuse Pro subscriber. Just trying to learn the ecosystem

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Firecore can choose to respond if they like but I doubt this is the case.

I bet they hand the audio stream over to the tvos api and the Apple TV takes care of the rest.