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Apple today seeded the release candidate version of an upcoming tvOS 15.5 update to developers for testing purposes, with the software coming one week after the release of the fourth beta.

Apple-TV-tvOS-15-Feature.jpg

Developers can download the new tvOS 15.5 update by downloading a profile onto the ‌Apple TV‌ using Xcode.

tvOS updates are typically minor in scale, focusing primarily on under-the-hood bug fixes and improvements rather than major outward-facing changes.

Though we don't often know what's new in tvOS during the beta testing process, we let MacRumors readers know when new updates are available so those who are developers can download it upon release.

As of now, we have not found new features in tvOS 15.5 and there's no word on what might be in the update beyond bug fixes and under-the-hood performance improvements.

Article Link: Apple Seeds tvOS 15.5 Release Candidate to Developers
 
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ThatGuyInLa

macrumors 6502a
Oct 26, 2012
668
762
Longs, SC
YouTube HDR playback support please. Please. Please. If it's something Google needs to do, then do it. Please.
Support of reading metadata from Amazon for auto mode switch too. FILMMAKER MODE. :)
 

nutmac

macrumors 603
Mar 30, 2004
5,512
5,629
YouTube HDR playback support please. Please. Please. If it's something Google needs to do, then do it. Please.
Support of reading metadata from Amazon for auto mode switch too. FILMMAKER MODE. :)
2nd gen Apple TV 4K supports YouTube HDR, but with a caveat. YouTube doesn't support tvOS's Match Dynamic Range feature. So to watch, you need to change Apple TV's Video Format setting to HDR (HDR10), then flip it back to SDR when you want to watch non-HDR contents.

I've reported this bug to Google earlier, as I am sure others have, but it remains unfixed.

To be fair, some of Apple's own features and apps don't support Match Dynamic Range either -- Photos and screensavers.
 

Realityck

macrumors 601
Nov 9, 2015
4,111
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Silicon Valley, CA
2nd gen Apple TV 4K supports YouTube HDR, but with a caveat. YouTube doesn't support tvOS's Match Dynamic Range feature. So to watch, you need to change Apple TV's Video Format setting to HDR (HDR10), then flip it back to SDR when you want to watch non-HDR contents.

I've reported this bug to Google earlier, as I am sure others have, but it remains unfixed.

To be fair, some of Apple's own features and apps don't support Match Dynamic Range either -- Photos and screensavers.
I have it connected to a LG OLED. If I set the 2nd gen 4K to its default 4K@60Hz HDR with last few betas. It correctly switches to Dolby Vision automatically and doesn't have any issues with YouTube working SDR to HDR10 automatically. Just don't set the ATV4K 2nd gen to have a GUI using 4K Dolby Vision at all. I have both match dynamic range and frame rate set to auto.
 
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ThatGuyInLa

macrumors 6502a
Oct 26, 2012
668
762
Longs, SC
I have it connected to a LG OLED. If I set the 2nd gen 4K to its default 4K@60Hz HDR with last few betas. It correctly switches to Dolby Vision automatically and doesn't have any issues with YouTube working SDR to HDR10 automatically. Just don't set the ATV4K 2nd gen to have a GUI using 4K Dolby Vision at all. I have both match dynamic range and frame rate set to auto.
Your reply and the other guys earlier have me running downstairs now! Thank you! (actually you are speaking of Beta which I don't run) So this probably won't work for current release?
 

ThatGuyInLa

macrumors 6502a
Oct 26, 2012
668
762
Longs, SC
2nd gen Apple TV 4K supports YouTube HDR, but with a caveat. YouTube doesn't support tvOS's Match Dynamic Range feature. So to watch, you need to change Apple TV's Video Format setting to HDR (HDR10), then flip it back to SDR when you want to watch non-HDR contents.

I've reported this bug to Google earlier, as I am sure others have, but it remains unfixed.

To be fair, some of Apple's own features and apps don't support Match Dynamic Range either -- Photos and screensavers.
Photos and Screensavers still??? GRRrrrr.
 

B/D

macrumors 65816
Mar 30, 2016
1,121
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wonder if it will ever passthrough uncompressed Dolby Atmos.

No. The Apple TV do not support Dolby True HD with the additional Atmos metadata layer. (hardware wise, it does not have the decoder).
 

thatJohann

macrumors 65816
Jul 5, 2013
1,192
919
NYC
Hmm I’m noticing eARC issues that I didn’t have before. Audio crackling. Restart resolves it but bummer.
 

InauguralHobbit

macrumors newbie
May 24, 2021
10
5
No. The Apple TV do not support Dolby True HD with the additional Atmos metadata layer. (hardware wise, it does not have the decoder).
Which is why Apple needs to add bitstream passthrough, so our soundbars & AVRs can decode the audio. Period.
 
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Realityck

macrumors 601
Nov 9, 2015
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Silicon Valley, CA
Which is why Apple needs to add bitstream passthrough, so our soundbars & AVRs can decode the audio. Period.
Normally you have the ATV4K HDMI going to AVR that decodes the audio utilized, then in turn outputs to the 4K TV assuming the AVR is 4K pass though capable. That way you don't need ARC/eARC unless your TV app need to be used instead by the AVR. You can even go that route with some more HDMI connected SoundBars.
 

InauguralHobbit

macrumors newbie
May 24, 2021
10
5
Normally you have the ATV4K going to AVR that decodes the audio utilized. That way you don't need ARC/eARC unless your TV app need to be used instead. You can even go that route with HDMI connected SoundBars.
Exactly my point. NO. That method is an archaic delivery schema for data. Leave "normally" in the past where it belongs.

We don't want to do that anymore a la HDMI 2.1 & its features: QMS, QFT, VRR via FRM (24.95Hz or 30/60Hz for YouTube), etc.

The way forward isn't the "normally" way.

Cease with the pre-HDMI 2.1 way of thinking, that's not the direction the industry is headed. Apple needs to catch up because it's clearly not pushing the envelope.
 

Realityck

macrumors 601
Nov 9, 2015
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Silicon Valley, CA
Exactly my point. NO. That method is an archaic delivery schema for data. Leave "normally" in the past where it belongs.

We don't want to do that anymore a la HDMI 2.1 & its features: QMS, QFT, VRR via FRM (24.95Hz or 30/60Hz for YouTube), etc.

The way forward isn't the "normally" way.

Cease with the pre-HDMI 2.1 way of thinking, that's not the direction the industry is headed. Apple needs to catch up because it's clearly not pushing the envelope.
Why is it a archaic delivery schema for the bitstream? The AVR is nothing more the a HDMI repeater, it does nothing to the video data, and is a far superior decoder for the audio going to amp driving your speakers. They have AVRs that are now 8K capable pass through. You trust the audio quality more from the source to TV and back to AVR?

Is this coming from the gaming perspective because you mentioned QFT? Lets also remember Apple is notorious slow on supporting HDMI standards, so everyone talks about HDMI 2.1 on a ATV 4K so we need to wait for the next ATV4K to see if its added.
 
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InauguralHobbit

macrumors newbie
May 24, 2021
10
5
Why is it a archaic delivery schema for the bitstream? The AVR is nothing more the a HDMI repeater, it does nothing to the video data, and is a far superior decoder for the audio going to amp driving your speakers. They have AVRs that are now 8K capable pass through. You trust the audio quality more from the source to TV and back to AVR?

Is this coming from the gaming perspective because you mentioned QFT? Lets also remember Apple is notorious slow on supporting HDMI standards, so everyone talks about HDMI 2.1 on a ATV 4K so we need to wait for the next ATV4K to see if its added.

Not at all from the gaming perspective. QMS because because I don't wish to wait 3 full-count seconds when playing media in Dolby Vision / HDR10--switching from SDR. QFT for the same reason, but in regard to switching from 59.95Hz to 24.95Hz for films & 30/60Hz for YouTube content.

And an HDMI 2.1 port is already on the 2021 2nd-Gen ATV 4K. These features can be & should be implemented via firmware within tvOS. This is no longer a hardware issue.

I prefer perma-MAT > PCM for 5.1 & MAT for Atmos. It's an annoyance dealing with pops & crackles when changing from 5.1 to Atmos content & vice versa, and it can't be good for the channel drivers in sound systems over time.

But I believe we're at an impasse. We simply believe one method is superior to the other. Connecting directly to a soundbar/AVR may have had the upper-leg pre eARC & HDMI 2.1, but now with bigger bandwidth pipelines for faster & larger data transfer that is no longer the case--or shouldn't be.

The software needs to be perfected & implemented. That will take time, I presume.

HDMI 2.1 bandwidth limits support QMS & QFT without the need for any of the gaming (120Hz) aspects. That aside, Apple really pushed this ATV in its marketing throes for Apple Arcade, so it's honestly a matter of Apple holding to their word of updating their software capabilities.
 
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Realityck

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But I believe we're at an impasse. We simply believe one method is superior to the other. Connecting directly to a soundbar/AVR may have had the upper-leg pre eARC & HDMI 2.1, but now with bigger bandwidth rates for faster & larger data transfer, but that is no longer the case.

The software needs to be perfected & implemented. That will

HDMI 2.1 bandwidth limits support QMS & QFT without the need for any of the gaming (120Hz) aspects. That aside, Apple really pushed this ATV in its marketing throes for Apple Arcade, so it's honestly a matter of Apple holding to their word of advancing their tech.
I am curious to what tvOS16 entails. There are many aspects of tvOS software that needs to be enhanced. ATV app has got several here upset because it chokes on large collections using library. It's also dumb you need Xcode to activate developer menu just to look at bit rates. I sure everyone here has a list of whats missing.
 
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InauguralHobbit

macrumors newbie
May 24, 2021
10
5
Sooooooo, bitstream would correct this horrendous mishap by Apple.
I'm really hoping this is a software fix and not a hardware fix.
If it is doable via underlying firmware within tvOS, it--in theory--could be implemented to the 1st gen ATV 4K, which is equipped with an HDMI 2.0a port, while using a High Speed HDMI cable w/ Ethernet (~18gbps throughput).

It would not be doable on ATV devices that are specced with an HDMI 1.4 port.

It should be easier still on the new 2nd gen ATV 4K from 2021, equipped with an HDMI 2.1 port, which would require a High Speed HDMI w/ Ethernet at minimum, or an Ultra High Speed HDMI cable at best.
 

InauguralHobbit

macrumors newbie
May 24, 2021
10
5
I and many others would just like uncompressed Dolby Atmos passthrough.
That is not possible on anything other than a BluRay disc where the audio is embedded into the record.

However compressed passthrough of lossless Atmos files would be viable with MAT 2.0/2.1 if you're into ripping BRs & using your own Plex media server. Compressed passthrough is virtually lossless, but not inherently so in its origin; slight, but important distinction.

Why 100% uncompressed is not possible is because most streaming platforms (ATV+, D+, Netflix, HBO Max) use Dolby Digital+, or the eAC3 codec to stream their Dolby 5.1 & Dolby Atmos files. There is a way to bypass this (a la the Dolby Access app on Xbox Series X allowing for Upmixed audio--permanent MAT container across the UX), but this would require Dolby certification of Apple's SoC.

We know Apple's secure & private practices regarding their tech; closed, end to end. I don't see Apple sending off an ATV device off to Dolby engineers to have a look inside the SoC. That would open up the possibility for reverse engineering.

To make that work would require a hefty amount of corporate cross-talk between Apple & Dolby. No doubt an expensive ordeal to arrive at an agreement, with NDAs to boot.

I want it as much as the next ATV user, but I'm not sure if Apple would spend the money on this specific "problem," for which in their mind already have it covered in the form of connecting the ATV directly to your soundbar / AVR--as another user here mentioned.

There is an exception, or caveat--ALAC--but I'm not sure how viable the codec would be for streaming in tandem with video. In theory, ALAC--currently used for Apple Music--could work since it can transport spatial audio metadata, and supports 16-bit/44.1 kHz through 24-bit/192 kHz. Bear in mind, this codec is used in individual files that carry audio only no longer than a few minutes [songs].

Changing the container for which Dolby 5.1 & Atmos files are carried would be different when taking into account the considerably larger file sizes due to them also being comprised of video. ~20, ~30, ~50 minute files for episodic media, and 90+ minutes for films.

To execute this would require a ton of backend work from not only Apple engineers, but also every single streaming platform (Netflix, D+, HBO Max, etc) to achieve compatibility, which once again poses one large problem: money.

It can be done, and there are multiple solutions, but any which one would require significant resources.

The best we could hope for is bitstream passthrough, which would put an end to audio delays & lip-sync / audio latency issues. This would be the simplest & cheapest, and would also allow for lossless passthrough of audio data within BR rips via PLEX, but not through the mainstream streaming platforms.

For those who choose to connect the ATV directly to their tv would require a tv with HDMI 2.1 & eARC with features such as Bitstream Passthrough on the tv itself for this to work properly. It would also require a soundbar or AVR with HDMI 2.1 & eARC as well. There are plenty of soundbars on the market with eARC, but the pool of products is significantly smaller with AVRs. <-- Link to a Yamaha RX-V6A AVR.
 
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B/D

macrumors 65816
Mar 30, 2016
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Which is why Apple needs to add bitstream passthrough, so our soundbars & AVRs can decode the audio. Period.

Very true. I agree. I think it wont happen though, because of Siri and other system sounds that Apple want to have mixed unto the audio stream.

I hope I´m wrong.
 
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