Just wondering why the Plex apple TV client is not able to direct play TrueHD codecs?
Infuse direct play’s the same content no issues. Any reason the Plex client can’t direct play TrueHD content? Is it a licensing issue?
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No it can’t.
Pms will transcode to pcm (losslessly).
No atmos.
Iirc, infuse has its own internal truehd decoder.
Apple itself does not support truehd at all.
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Any chance Plex does something similar to what infuse is doing and adds the proper decoder under the hood of the Plex client? I prefer the interface of Plex player but infuse on Apple TV direct plays TrueHD no problem (and literally everything else besides music content).
Probably very unlikely, but your guess is as good as anyone else’s.
If apple ever decided to support actual pass through, then it would not need any player decoding, it would be up to the avr/sound bar/tv to decode it.
But I’m guessing that since the Apple TV is intended for streaming services, that do not use truehd, that won’t happen either.
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So we don’t really need Apple to support anything on the ATV.
The choices aren’t between transcoding TrueHD on the server or having Apple support passthrough or decoding.
The option we want is right in the middle – to have the Plex decode TrueHD on the client.
Plex does this for DTS/DTS-HD with the DCA decoder. You can direct-play a file with DTS/DTS-HD audio and the mpv player in the Plex app will do the decoding to multichannel PCM on the client, so you get the benefits of Direct Play for fast playback and stream navigation, etc.
Even modifying the tvOS Plex profile to add truehd to the list of Direct Play audio codecs, the decoder in mpv doesn’t seem to get engaged.
So, since Plex is using mpv as the Enhanced Player on Apple TV, and mpv has a Dolby TrueHD decoder built in, the question still stands — why isn’t Direct Play supported in this scenario?
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With DTS-HD, only the DTS core is decoded, not the DTS-HD stream. TrueHD decoding would require a license for the device, and not just doing something with mpv
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OK, that’s good info, @DaveBinM, thank you.
So what you’re saying — where the DCA decoder for DTS-HD only decodes the DTS core — does that only apply on the client when using Direct Play with the mpv player?
If we don’t modify the tvOS.xml profile to include dca in the audio codecs for Direct Play, then full, lossless DTS-HD and Dolby TrueHD streams are transcoded to multichannel FLAC on the server and the mpv player decodes FLAC to multichannel PCM on the client?
No, that applies everywhere. The only time DTS-HD will be decoded is if you’re on a device that supports passthrough, and the DTS-HD audio is passed through to the AVR/soundbar. Otherwise, it’s just the DTS core
Thanks for the clarification. Was not aware any DTS-HD streams were effectively playing as lossy DTS streams.
So what about the OP — since TrueHD streams can’t be Direct Played, when they’re transcoded on the server to FLAC (assuming there is no TrueHD pseudo “core” stream available), is that a lossless transcode of TrueHD to multichannel FLAC (sans Atmos)?
And if so, why is that handled differently than DTS-HD? Is Plex paying Dolby for a TrueHD decoder license that can only be used on PMS and not on the client, while not paying for a DTS-HD decoder license at all?
Yes, it’s a lossless transcode for TrueHD to FLAC. I can’t really go into licensing specifics, but any codecs that we use, we meet the licensing requirements for.
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