[AUDIO] hi-rez audio

[benogil]

This is from another forum - so I am not certain it is timely or correct, but it may help.
Short answer - yes, but with a lot of pain. The limitation is the software that runs on NMT. It can output hi-rez audio only via HDMI (that's a hardware limitation, SPDIF can't handle multichannel hi-rez) and only when it's muxed into MPEG TS stream in LPCM form. You can output up to full HDMI v1.3 spec - 8x24x192. this works fine with my PCH A110 and Marrantz SR5003 - I can listen to DVDA rips in full glory. Obviously I don't want to keep my rips in MPEG TS, so I decode into WAV/LPCM and then mux into MPEG TS when I want to listen to something on Marrantz.

PCH would be a much better device if it had normal support for hi-rez WAV or FLAC files (FLAC may not be possible due to CPU limitation). Since it's not a priority for the majority of PCH users, it's unlikely to get implemented any time soon.

Since PCH is very extendable, there is definitely a way to create a backend streaming solution that would transcode FLACs on the fly and mux them into MPEG TS. I have almost done this in llink, but due to the fact that tsmuxer cannot read from pipe, there is a long delay before the streaming starts while FLAC is being decoded into WAV. ffmpeg and mencoder can create MPEG TS directly from FLAC, but for some reason PCH doesn't play the streams produced by ffmpeg/mencoder, I was only able to playback tsmuxer encoded streams.

So, someone with enough experience can create a script that would take two parameters - FLAC file and pipe location and output the FLAC as LPCM MPEG TS into the pipe. Such script would enable playback of hi-rez multichannel hi-rez FLACs on PCH. It's not as good as native PCH support for multichannel hi-rez FLACs would be (no way to rewind, fast forward, etc) but it would be a good start.

Ben

[6p14pev]

There is high-resolution multi-channel audio, and high-resolution two-channel audio.

As far as 2-channel WAV/FLAC goes, NMTs have no problem providing high-resolution output upto 192kHz on the optical or co-ax s/pdif port. There are many threads here that discuss this.

Multi-channel FLAC support does not exist. I do not know if it will be implemented in the current generation of NMTs. There is a big thread on this in the Feature Request section.

[daniel_owen_uk]

(04-23-2009 06:06 PM)benogil Wrote:  This is from another forum - so I am not certain it is timely or correct, but it may help.
Short answer - yes, but with a lot of pain. The limitation is the software that runs on NMT. It can output hi-rez audio only via HDMI (that's a hardware limitation, SPDIF can't handle multichannel hi-rez) and only when it's muxed into MPEG TS stream in LPCM form. You can output up to full HDMI v1.3 spec - 8x24x192. this works fine with my PCH A110 and Marrantz SR5003 - I can listen to DVDA rips in full glory. Obviously I don't want to keep my rips in MPEG TS, so I decode into WAV/LPCM and then mux into MPEG TS when I want to listen to something on Marrantz.

Pretty much correct, it's High Definition audio, there is no resolution in audio.

Quote:PCH would be a much better device if it had normal support for hi-rez WAV or FLAC files (FLAC may not be possible due to CPU limitation). Since it's not a priority for the majority of PCH users, it's unlikely to get implemented any time soon.

The PCH can handle FLAC and WAV, unfortunately not multichannel FLAC in an MKV, but for audio, 2 channel FLAC is fine.


Since PCH is very extendable, there is definitely a way to create a backend streaming solution that would transcode FLACs on the fly and mux them into MPEG TS. I have almost done this in llink, but due to the fact that tsmuxer cannot read from pipe, there is a long delay before the streaming starts while FLAC is being decoded into WAV. ffmpeg and mencoder can create MPEG TS directly from FLAC, but for some reason PCH doesn't play the streams produced by ffmpeg/mencoder, I was only able to playback tsmuxer encoded streams.

So, someone with enough experience can create a script that would take two parameters - FLAC file and pipe location and output the FLAC as LPCM MPEG TS into the pipe. Such script would enable playback of hi-rez multichannel hi-rez FLACs on PCH. It's not as good as native PCH support for multichannel hi-rez FLACs would be (no way to rewind, fast forward, etc) but it would be a good start.

Ben
[/quote]

[SirNickity]

While, true, there is no pixel resolution in audio, the terms definition and resolution are otherwise essentially synonymous. Many professional audio components refer to the word length (bit-depth) as resolution, for instance. Not to be nit-picky, ... well.. ok... yeah, I'm being nit-picky.

Also... being forced to 2 channels is definitely not OK for audio. Not when you've invested in a library of DVD Audio, Super Audio CD, or other high-resolution (definition?) audio formats which were engineered in >2 channels. :-)

In these cases, I would almost prefer to go ahead and make it a video file with a dummy video track, but since PCH is incapable of multichannel FLAC in video files, that doesn't help much either.

[jofa]

(04-24-2009 03:30 PM)daniel_owen_uk Wrote:  I have almost done this in llink, but due to the fact that tsmuxer cannot read from pipe, there is a long delay before the streaming starts while FLAC is being decoded into WAV. ffmpeg and mencoder can create MPEG TS directly from FLAC, but for some reason PCH doesn't play the streams produced by ffmpeg/mencoder, I was only able to playback tsmuxer encoded streams.

Could you please, please, post the steps in how to convert audio file to mpeg ts.
Both from WAV file, and perhaps also from a DVD Audio Iso.
Hmmm, it is christmas, right?

/jofa

[daniel_owen_uk]

That wasn't me, it was just a bad post (quote tags).

[peterjcat]

(04-29-2009 09:12 PM)SirNickity Wrote:  While, true, there is no pixel resolution in audio, the terms definition and resolution are otherwise essentially synonymous. Many professional audio components refer to the word length (bit-depth) as resolution, for instance. Not to be nit-picky, ... well.. ok... yeah, I'm being nit-picky.

In this case you're being nit-picky about someone else's nit-pickiness, so I think it's OK

I've always thought that "definition" and "resolution" could both be used for both audio and video. DTS thinks so too... (DTS-HD High Resolution).

[nycaleksey]

(04-30-2009 01:22 PM)jofa Wrote:  Could you please, please, post the steps in how to convert audio file to mpeg ts.
Both from WAV file, and perhaps also from a DVD Audio Iso.
Hmmm, it is christmas, right?

/jofa

Hi,

I'm the original poster of the above quoted post from AVSForum.

Converting .wav to .ts is very simple - just use TSMuxer (http://www.videohelp.com/tools/tsMuxeR). Add a single WAV file and create a TS.

You can use many different tools to extract audio track from DVD ISO. I use DVDDecrypter for this purpose.

[jofa]

(05-06-2009 02:14 PM)nycaleksey Wrote:  Hi,

I'm the original poster of the above quoted post from AVSForum.

Converting .wav to .ts is very simple - just use TSMuxer (http://www.videohelp.com/tools/tsMuxeR). Add a single WAV file and create a TS.

You can use many different tools to extract audio track from DVD ISO. I use DVDDecrypter for this purpose.

Thank's
I tried tsMuxeR with partial success. It complained about the sample rate on most of my files, but some worked.
The only one I succeeded with was 96 kHz 24 bit 5.1, and I don't know if my HDMI 1.2a receiver can handle that.
So far I have never manged to get any sound at all with PCM sound and HDMI set to 5.1. Very, very annoying.

Can you really extract the AUDIO_TS part of a DVD Audio iso using DVD Decryptor?
And how is then the MLP(?) coded audio converted to wav?

br
Jofa

[nycaleksey]

(05-07-2009 12:37 PM)jofa Wrote:  Thank's
I tried tsMuxeR with partial success. It complained about the sample rate on most of my files, but some worked.
The only one I succeeded with was 96 kHz 24 bit 5.1, and I don't know if my HDMI 1.2a receiver can handle that.
So far I have never manged to get any sound at all with PCM sound and HDMI set to 5.1. Very, very annoying.

Can you really extract the AUDIO_TS part of a DVD Audio iso using DVD Decryptor?
And how is then the MLP(?) coded audio converted to wav?

br
Jofa

Jofa,

Sorry, there was a misunderstanding, DVDDecrypter is used for extracting AC3/LPCM tracks from standard video DVDs. DVD-Audio is a totally different beast, search for "DVDA Explorer" tool - it will extract all tracks in native form and even convert MLP to WAV if needed.

tsMuxeR worked for all multichannel hidef content that I tried which is mostly 6ch/24bit/96khz. Maybe it fails with other types, I don't know.

According to http://en.wikipedia.org/wiki/HDMI#Versions HDMI 1.2a capable receiver should be able to support up to 8/192/24 content, so as along as your receiver support LPCM over HDMI it should be playing the content just fine. Make sure you configure you PCH for "5.1" surround output for HDMI in "Audio/Video" section of setup, otherwise it will downsample everything to 2ch.

As I wrote before, my Marrantz SR-5003 receiver can playback 6/24/96 LPCM content over HDMI just fine.

[jofa]

My Marantz SR-7001 can not.
And I don't know which unit to blame. I'm suspecting the HDX since Marantz did a service on the receiver and claimed that it played 5.1 ch PCM. Unfortunately I have no other HDMI source to test with. Very annoying!

/J