Beginner questions regarding Dolby Atmos and Vision

Hello,

Long time Plex user/disc ripper, just starting to grasp 4k/HDR/DV. I recently started an Infuse trial and just want to make sure I’m understand everything.

Atmos
Infuse supports Dolby Atmos when using E-AC3 audio tracks. That’s different than the TruHD tracks that are on UHD discs, correct? What is playing if a TruHD track is selected? Would I need to transcode the TruHD track to E-AC3 to get the most fidelity from Infuse? Does the E-AC3 track simply add height channels(which I don’t have), or is there more to it?

Vision
I see Handbrake does a DV conversion to profile 8. Is that enough to get DV from MEL discs (like The Matrix)? Is it even worth it on FEL discs (like BTTF)?

I’ve got some discs that I know how to rip and MakeMKV and I’m very familiar with Handbrake. I’m just trying to make sure I can get the most data/fidelity with the available tools. I thought I have more questions, but that’s it for now.

I suggest you have a read through those first, then the community can help with any residual questions you may have.

Yes, I’ve read those, as well as others. Still looking for clarity. Dolby Vision is something else…

To attempt to add this, audio wise for True-HD Atmos you will have no loss in audio fidelity except for the actual Atmos metadata. If you are using a True-HD capable receiver Infuse will decode the Audio and output it as PCM (but again you are losing no audio fidelity barring the Atmos Metadata.)

As for Dolby Vision there are three (main) varieties. Profile 5 and Profile 8 which will play as Dolby Vision in Infuse. Unfortunately Blu-Ray uses profile 7 which will only play as HDR10. If you desperately need Dolby Vision there are tools that can do this.

GitHub - R3S3t9999/DoVi_Scripts: User-friendly / drag & drop scripts to process any HDR / Dolby Vision files and more... and also here on this forum Dolby Vision Profile 7 & 8 support (.ts/.mkv files) - #846 by speedy

I personally have only used the 2nd link and did work very well.

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Thanks, @Hitsville.

I should have framed my questions more from the workflow standpoint, going from disc to file.

On the Atmos side, from what I’ve read, you can’t really go from Atmos to E-AC3. While you can get an E-AC3 output I think it loses the Atmos metadata(which is more than height channels), much like going from Atmos to LPCM. Which is unfortunate, as I do think I can hear a difference (though I haven’t done much comparing).

Yes, I’ve used @speedy’s script (awesome, btw!)as well as what is built in to Handbrake, using VideoToolBox. I think they’re doing the same thing.
script output:
HDR format : Dolby Vision, Version 1.0, Profile 8.1, dvhe.08.06, BL+RPU, no metadata compression, HDR10 compatible / SMPTE ST 2086, Version HDR10, HDR10 compatible
Handbrake:
HDR format : SMPTE ST 2086, Version 1.0, dvhe.08.06, BL+RPU, no metadata compression, HDR10 compatible / Dolby Vision, HDR10 compatible / SMPTE ST 2086, HDR10 compatible

I think with that extra layer of FEL not being easily available (yet), I don’t really desperately need the Dolby Vision.

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It will play as lossless 7.1 PCM

Pretty much. An Atmos E-AC3 track is 5.1 with metadata that allows sounds to be extracted from the 5.1 base and placed in other speakers (such as heights, rear surrounds, or front wide speakers).

If you don’t have those other speakers, then don’t worry about atmos.

As far as I know, there is no way to convert TrueHD Atmos to E-AC3 Atmos.

What you can do, is find an Atmos WEB-DL copy of the same movie and merge in the EAC3 audio and adjust its audio delay. You can do this using an app like MKVToolNix.