VVVV.Audio Windows System Audio Support (WASAPI)

tonfilm · February 23, 2020, 8:02pm

Due to popular demand VVVV.Audio now supports WASAPI, the latest windows audio driver model and the only system audio driver model that supports latencies low enough for music visualization with live input. Except for ASIO of course, which allows even lower latencies and has better performance, but needs third party drivers.

The good thing under Windows 10 is that for a while (if you did all updates) the latency setting of WASAPI devices is on lowest by default.

WASAPI is also the only driver model that allows having a loopback device for every audio output endpoint.

That means that you can now get the current sound playing in windows as an audio input. And that other applications can still use the same audio device.

However, there is one thing you have to take care of since VVVV.Audio doesn’t do any resampling: The sample rate of the selected input must match the sample rate of the output device. The AudioEngine node has an output that lists all WASAPI devices and their sample rates.

Download:
VVVV.Audio_AnyCPU_V19_preview.zip

Important: Make sure that you delete all occurrences or VVVV.Audio.Core.* and NAudio.* files from the vvvv installation folder before trying the new pack.

and here is a test patch:
WasapiDebug.v4p (20.6 KB)

Let me know whether it works and especially what doesn’t.

motzi · February 23, 2020, 8:45pm

just did a quick test and could not get it to work. AudioEngine node stays red and TTY shows this exception:

00:00:23 ERR : Exception occurred during creation of plugin: The composition produced a single composition error. The root cause is provided below. Review the CompositionException.Errors property for more detailed information.
1) Method not found: 'Boolean NAudio.CoreAudioApi.MMDeviceEnumerator.HasDefaultAudioEndpoint(NAudio.CoreAudioApi.DataFlow, NAudio.CoreAudioApi.Role)'.

 Resulting in: An exception occurred while calling the 'OnImportsSatisfied' method on type 'VVVV.Nodes.AudioEngineNode'.

Resulting in: Cannot activate part 'VVVV.Nodes.AudioEngineNode'.
Element: VVVV.Nodes.AudioEngineNode -->  VVVV.Nodes.AudioEngineNode -->  TypeCatalog (Types='VVVV.Nodes.AudioEngineNode').

Resulting in: Cannot get export 'VVVV.Nodes.AudioEngineNode (ContractName="VVVV.PluginInterfaces.V1.IPluginBase")' from part 'VVVV.Nodes.AudioEngineNode'.
Element: VVVV.Nodes.AudioEngineNode (ContractName="VVVV.PluginInterfaces.V1.IPluginBase") -->  VVVV.Nodes.AudioEngineNode -->  TypeCatalog (Types='VVVV.Nodes.AudioEngineNode').

Resulting in: Cannot set import 'VVVV.Hosting.IO.PluginContainer.PluginBase (ContractName="VVVV.PluginInterfaces.V1.IPluginBase")' on part 'VVVV.Hosting.IO.PluginContainer'.
Element: VVVV.Hosting.IO.PluginContainer.PluginBase (ContractName="VVVV.PluginInterfaces.V1.IPluginBase") -->  VVVV.Hosting.IO.PluginContainer

did a fresh install of b39 x64 + addonpack (nothing else) to verify if there is not an NAudio install i overlooked somewhere.

tonfilm · February 23, 2020, 8:46pm

then there is some old NAudio.dll floating around in your vvvv folder or packs? did you delete all of them, including all VVVV.Audio.Core files?

motzi · February 23, 2020, 9:11pm

true - found two instances of naudio and vvvv.audio.core in

lib/core
lib/nugets/vl.corlib…

and a third in

VVVV.Audio\girlpower\plugins\VAudioOSCTester\bin\Dynamic

removing them makes it work nicely.

this is really awesome, thanks a lot tebjan! finally audio loopback without additional tools - this makes audiohandling so much easier.

domj · February 27, 2020, 10:11pm

Very excited about this, thought you were dead set on keeping it ASIO only :)

Loopback and non-exclusive mode allowing all system sounds to work should be very nice. Seems there is also an exclusive mode for WASAPI which could yield similar latencies to ASIO4ALL while staying with stock drivers.

I tested it out but unfortunately can’t get it to work though. Removed the extra NAudio.dll like motzi but the AudioEngine node is still red and this keeps filling the TTY:

00:00:24 ERR : Exception occured in TMPluginWrapperNode.Evaluate
00:00:24 ERR : Method not found: 'Void VVVV.Audio.AudioEngine.ChangeDriverSettings(System.String, System.String, Int32, Int32, Int32, Int32, Int32)'.

tonfilm · February 28, 2020, 3:04am

@domj

it seems you didn’t delete the VVVV.Audio.Core files.

domj · February 28, 2020, 10:27am

You are of course correct, now works perfectly. Vvvvery cool.

domj · February 28, 2020, 10:55am

Found one problem: Gist node crashes vvvv now (When WASAPI driver is used)

tonfilm · February 28, 2020, 11:56pm

Thanks for finding this bug, will fix it for the next version.

microdee · February 29, 2020, 10:52am

it also crashes when the sample rate is not set to 44.1 khz, even in asio

motzi · April 24, 2020, 2:08pm

@microdee cannot confirm crashes with other samplerates than 44.1. lots of exceptions though when changing drivers…

@tonfilm the new hybrid Audioengine node providing access to ASIO and WASAPI is a little confusing from a usability point of view. even when ASIO drivers are selected, the WASAPI pins (inputdevices and deviceinfos) stay visible/selectable. especially beginners will be confused by the fact, that for ASIO there is only a driver selection while for WASAPI the driver sets the outputs and there is a separat input pin.
as a solution one could consider to have two versions (audioengine (vaudio.asio) and audioengine (vaudio.wasapi)) or just hide the wasapi pins when selecting an asio driver.

just a thought…

reaktant · June 20, 2020, 5:06pm

Is it possible to get the WASAPI driver inside VL somehow?

tonfilm · June 21, 2020, 1:16am

@reaktant unfortunately, this branch of VVVV.Audio is on ice at the moment. i haven’t found a way to synchronize input with output while maintaining acceptable latency.

ASIO is very elegant, the input and output buffers always have the same size and happen at the exact same time. for WASAPI neither is true. even worse, input and output aren’t guaranteed to have the same sample rate. this makes things awefully more complex and i didn’t have the time to look into that…

but the branch is public, anyone is welcome to implement an optimal ring buffer. if anyone does, please let me know, i am happy to help.

reaktant · June 21, 2020, 2:15pm

thanks for the explanation!
so does this fall into the “possibe but somehow tricky” category?
using asio had some side effects i hoped to get rid of by using wasapi.
in case you haven’t seen it yet, some things i found along the topic:

https://social.msdn.microsoft.com/Forums/en-US/c4fd959b-a0c8-40a0-b037-f949c2428337/audio-inputoutput-synchronization-under-wasapi

tonfilm · June 21, 2020, 3:46pm

yes, certainly possible, but it’s a bit of work to do it properly.

thanks for the links, I haven’t seen them yet.