Are muted sources calculated? Multichannel .wav playback with audioplayer.cpp

[ridgerider]

Hey, it's me again :)

Two questions on the way to the next listening test using the BRS Renderer:

1) Do muted sources and/or sources with no audio input occupy CPU resources on my computer? I want to compare different BRIRs with several sources (speakers) playing at the same time. While I'm confident my Macbook can handle one set of sources (e.g. 12) I doubt it will be able to calculate multiples of it..

2) I have never used the build in audioplayer of the SSR, but it could be the right tool this time. Is there a channel limit for the playback of multichannel .wav files? If yes, would the playback of multiple mono wav be a workaround (sync?)? 

My first try with a mono file linked to a BRIR failed: Error: AudioPlayer::Soundfile: ERROR:  Connecting chainsetup failed: "Enabling chainsetup: AUDIOIO-JACK: Unable to open JACK-client" (audioplayer.cpp:310)

Warning: AudioPlayer: Initialization of soundfile 'Scenes/VirtuelleAkustik/audio/1.wav' failed! (audioplayer.cpp:87)

Any idea?

Any help is much appreciated! Thanks!

Jan

[Matthias Geier]

On Sun, Jun 25, 2017 at 10:09 PM, ridgerider wrote:
> Hey, it's me again :)
>
> Two questions on the way to the next listening test using the BRS Renderer:
>
> 1) Do muted sources and/or sources with no audio input occupy CPU resources
> on my computer?

No and no.

Well strictly speaking they do need *some* resources, but
significantly less than sources with a non-zero signal.
I would probably say something like "negligible" ...

But don't take my (or anyone's) word for it, please check if that's
also true in your situation.
And if not, please report back, so we can fix it!

> I want to compare different BRIRs with several sources
> (speakers) playing at the same time. While I'm confident my Macbook can
> handle one set of sources (e.g. 12) I doubt it will be able to calculate
> multiples of it..

Shouldn't be a problem.
Just note that if you make a crossfade between two sets, both will be
active for one block during the crossfade, which might create a CPU
spike.

In the past, I've been running out of memory far quicker than out of CPU.

> 2) I have never used the build in audioplayer of the SSR, but it could be
> the right tool this time. Is there a channel limit for the playback of
> multichannel .wav files?

TBH, I don't know if there is a limit.
I think we have used 64-channel files in the past, but I guess many
more are possible.

How many channels are you talking about?

Note that you might have to increase the number of available JACK
ports when starting jackd.

> If yes, would the playback of multiple mono wav be
> a workaround (sync?)?

The SSR uses ecasound for file playback, and all instances are
synchronized via JACK transport.
This shouldn't be a problem either way.

If you have many channels, reading from a single multichannel WAV file
might be more efficient than reading from many mono files spread all
over your hard disk.
But probably you shouldn't worry about that.

> My first try with a mono file linked to a BRIR failed: Error:
> AudioPlayer::Soundfile: ERROR: Connecting chainsetup failed: "Enabling
> chainsetup: AUDIOIO-JACK: Unable to open JACK-client" (audioplayer.cpp:310)
>
> Warning: AudioPlayer: Initialization of soundfile
> 'Scenes/VirtuelleAkustik/audio/1.wav' failed! (audioplayer.cpp:87)
>
> Any idea?

Hmmm, strange.
I assume jackd is started?

In the past, there have been all sorts of problems with JACK and ecasound.
Sometimes it helps to try different versions of either.

cheers,
Matthias

[ridgerider]

In case anybody finds this thread searching for the same error:

The solution was actually listed in the "Known Issues"-section of the SSR manual: "Long paths to audio files on Mac OS X". Turns out my path was too long.

Cheers,

Jan