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Unmanic / unmanic

Unmanic - Library Optimiser
GNU General Public License v3.0
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Audio Transcoding Question #214

Open Hime0698 opened 3 years ago

Hime0698 commented 3 years ago

Hey y'all.

This might not be quite the right place to ask this, but since I'm using unmanic for this task I figured id go to the source.

What settings/format should I use to transcode audio in order to preserve Dolby Atmos if it exists in the file? Or is that not possible and I should just skip audio transcoding.

Josh5 commented 3 years ago

FFmpeg is not able to do this.

What are you trying to achieve? It is possible to go from, for example, DD 7.1 to FLAC 7.1. I could create a plugin to do that for you. But encoding more than 6 channels (eg 5.1) Dolby digital is not possible without an expensive commercial encoder.

Hime0698 commented 3 years ago

ok, so it sounds like its not possible to reincode (to conserve space) without loosing the Dolby Atmos track

Josh5 commented 3 years ago

Well just to be clear. You cannot transcode the Atmos track, but you can transcode everything else

Hime0698 commented 3 years ago

So how would I go about doing that?

Transcoding all the audio except the atmos track that is.

(BTW LOVING the new update!)

Josh5 commented 3 years ago

well like I said above I can create a plugin to do what you need. If you could be very specific on what you want the output codecs to be, I can figure out what we need in a plugin to do that.

Hime0698 commented 3 years ago

I am not totally sure what I want it to be. Something smaller than MP3 that would still support regular surround sound it it exists and not mess with Atmos if it's there. And supported by plex. Maybe AAC? Honestly I am pretty New to audio transcoding and don't know much about it.

Thanks for the help and the offer!

Josh5 commented 3 years ago

I personally think your options would be FLAC or AAC.

FLAC is your best option for a codec for multi-channel lossless audio. I am not sure how well supporte it would be by devices, but it will work fine in Plex. But if you are transcoding to FLAC, you will end up with larger files over ac3/dolby digital.

AAC is really good for compression and quality and it is very widely supported by devices. If you are going for a codec that will be supported by as many playback devices as possible, then I would suggest AAC.

martadinata666 commented 3 years ago

I prefer to skip audio trancode, and let the media server adjust it on the fly. As audio doesn't really taxing cpu. converting to lossless flac also viable options.