ATMOS via Foobar2000??

[gorman]

At the time I described that I was playing Atmos streams in Foobar but just the core. I did not have an AVR connected and assumed it would work. Other users found Foobar does not bitstream via HDMI.

Tried asking, after some investigation...

https://hydrogenaud.io/index.php/topic,123910.0.html

 

[humprof]

Tried asking, after some investigation...

https://hydrogenaud.io/index.php/topic,123910.0.html

Good on you. Fingers crossed.

 

[fripppp]

Tried asking, after some investigation...

https://hydrogenaud.io/index.php/topic,123910.0.html

You can use the Command Line Decoder Wrapper, which the FFMPEG wrapper is derivative of, in order to specify your own FFMPEG arguments per file extension. However I believe what you're requesting can't be done, as Foobar2000 has to read it first before it can get to your reciever. The only way to play Atmos through Foobar2000 would either be a software decoder, or writing a custom Foobar2000 plugin that enables passthrough for Atmos audio, which would take out a lot of features of Foobar2000 when playing Atmos, such as converting and DSPs. I use a custom software decoder I wrote using the "Cavern" library to decode E-AC3 Atmos files with the Command Line Decoder Wrapper in Foobar2000.

 

[gorman]

You can use the Command Line Decoder Wrapper, which the FFMPEG wrapper is derivative of, in order to specify your own FFMPEG arguments per file extension. However I believe what you're requesting can't be done, as Foobar2000 has to read it first before it can get to your reciever. The only way to play Atmos through Foobar2000 would either be a software decoder, or writing a custom Foobar2000 plugin that enables passthrough for Atmos audio, which would take out a lot of features of Foobar2000 when playing Atmos, such as converting and DSPs. I use a custom software decoder I wrote using the "Cavern" library to decode E-AC3 Atmos files with the Command Line Decoder Wrapper in Foobar2000.

Well, first of all... where's the link for your custom sofware decoder with instructions?

The whole point of whatever passthrough engine is to avoid touching the audio, so the lack of conversion and DSP functionality would be par for the course, don't you think.

I also note that having SPDIF wav in FLAC allows one to passthrough DD, DTS and DTS 96/24 to an AVR, with no DD or DTS decoder installed in foobar.

It's probably "just" a matter to understand whether truehd atmos files are signed, unsigned, little or big endian, etc. before one can compress them with FLAC. And maybe not, I'm not sure, obviously.

 

[fripppp]

Well, first of all... where's the link for your custom sofware decoder with instructions?

The whole point of whatever passthrough engine is to avoid touching the audio, so the lack of conversion and DSP functionality would be par for the course, don't you think.

I also note that having SPDIF wav in FLAC allows one to passthrough DD, DTS and DTS 96/24 to an AVR, with no DD or DTS decoder installed in foobar.

It's probably "just" a matter to understand whether truehd atmos files are signed, unsigned, little or big endian, etc. before one can compress them with FLAC. And maybe not, I'm not sure, obviously.

I used quite a bit of decompiled code from the Cavernize demonstration program itself, which is not open source, so I don't think I would be allowed to distribute it, but I'll see what I can do when I get home. Anyone with a little bit of programming knowledge could put something together like I did though. It's definitely not optimal though.

I hadn't considered Foobar being able to send the raw bitstream though, I couldn't find much info about that online, but if it can play DTS 96/24 like that as you said then it might be a promising lead.

I was just trying to say that I'm pretty sure the Command Line Decoder, and in turn the FFMPEG addon, were both written with Foobar processing the audio first in mind, and you'd probably need a custom addon for TrueHD passthrough, but if Foobar can send the raw bitstream then it might be possible. Did you try the Command Line Decoder Wrapper to start FFMPEG with custom instructions?
I'm at work so can't test it now, but

ffmpeg -i %s -f W64 -map 0:0 -acodec pcm_f32le

Should be the proper input for what you asked, although I couldn't find much data on outputting raw bitstream via FFMPEG. Best of luck.

 

[gorman]

Should be the proper input for what you asked, although I couldn't find much data on outputting raw bitstream via FFMPEG. Best of luck.

Unable to open item for playback (Could not process decoded file: Unsupported format or corrupted file)

Unfortunately I've been searching far and wide and yeah, there's not much info around on the subject.
But there's plenty of programs, by now, that are based on ffmpeg and are capable of passthrough, which is why I hope a solution can be found.

As far as what fb2k does when bistreaming AC3, DTS or DTS 96/24, it does so when first the .ac3 or .dts files are encapsulated in a wav file (which can be even compressed to FLAC or ALAC). Foobar decodes the WAV (or FLAC or ALAC) and the content is passed through, bitperfect.

Probably a similar "trick" would be needed for TrueHD Atmos or DTS-X (although not much music content in DTS-X unless I'm mistaken).

EDIT
For reference, the original script to encapsulate AC3/DTS in WAV was this: spdifconvert/spdifconvert.py at master · steve-tregidgo/spdifconvert
Now AudioMuxer does it through a GUI but maybe looking at that code can give you ideas, I don't know.

The author described it like this:
spdifconvert.py is a Python script which takes as input an AC3 or DTS file (sourced from a DVD) and encapsulates it in an IEC61937 stream. This stream is then wrapped in a WAV file which can be played over an S/PDIF link with no modifications (ie no volume adjustments); a digital receiver will be able to interpret the AC3 or DTS data contained within this stream (assuming the receiver knows the AC3/DTS formats).

 

[HomerJAU]

There is no Atmos decoder in ffmpeg.

 

[gorman]

There is no Atmos decoder in ffmpeg.

I don't want to decode it, I want to pass it to my AVR untouched, as other programs have long been capable of.

 

[M-K]

I don't own an Atmos setup but I've read and heard that KODi actually can pass through Atmos via HDMI to your AVR.
So I'm wondering that this isn't possible with foobar. Would be good to know how to do ...

 

[gorman]

I don't own an Atmos setup but I've read and heard that KODi actually can pass through Atmos via HDMI to your AVR.
So I'm wondering that this isn't possible with foobar. Would be good to know how to do ...

Yes, this (Kodi on Windows) the main point of my reasoning. If they do it (and Kodi is based on FFMPEG), there must be a way to do it. LAV Filters do it as well, several other programs as far as I'm aware...

 

[VoidX]

I used quite a bit of decompiled code from the Cavernize demonstration program itself, which is not open source, so I don't think I would be allowed to distribute it

Wait, you made it real-time? I was struggling to do so. Cavernize is open, it's just not in the repo root, but under CavernSamples. You can do anything you want with it if you credit me and it's ad-free.