Re: AUGraph reconfiguration in response to route change
Re: AUGraph reconfiguration in response to route change
- Subject: Re: AUGraph reconfiguration in response to route change
- From: Sven Thoennissen <email@hidden>
- Date: Tue, 10 Jul 2018 11:20:01 +0200
Hello,
It may have to do something with the property listener. Have you tried using
AVAudioSession.routeChangeNotification instead?
Did you connect more than 8 AUMIDISynth to your mixer? (IIRC 8 is the maximum
possible, at least with AVAudioMixerNode)
In any case it is hard to tell without seeing code. I recommend to set up a
minimal test project with only 1 AUMIDISynth.
Have you considered using AVFoundation classes instead of the old V2 API? (at
least to reproduce the problem)
Best regards,
Sven
> Am 09.07.2018 um 21:32 schrieb Bartosz Nowotny <email@hidden>:
>
> Hello,
>
> I am trying to programmatically reconfigure AUGraph at runtime, in response
> to a route change.
>
> My set up consists of a couple of AUMIDISynth nodes connected to a multi
> channel mixer node which in turn is connected to RemoteIO node. This set up
> works fine and I am able to produce audio by sending MIDI note on/off events.
>
> I want to avoid audio data resampling at any point in the graph. I can start
> with a properly set up AUGraph that has all audio units use the same sample
> rate (starting from midi synths, through mixer to remote IO). Route changes
> (e.g. plugging in headphones) can change the output sample rate and thus
> introduce resampling and other side effects.
>
> To respond to a route change I set up a property listener for StreamFormat on
> my IO unit. When the stream format changes, I call a method that reconfigures
> the AUGraph in the following manner:
> 1. Stop the AUGraph
> 2. Uninitialize the AUGraph
> 3. Clear all graph connections
> 4. Set mixer output sample rate (propagates to IO input sample rate)
> 5. Set synth output sample rates (propagates to mixer input sample rates)
> 6. Connect synth nodes to mixer node
> 7. Connect mixer node to IO node
> 8. Update, Initialize and Start the AUGraph
>
> None of the above operations returns an error result.
>
> The issue occurs when I send some note on/off events - the app crashes. What
> am I missing?
>
> Regards,
> Bartosz Nowotny
> _______________________________________________
> Do not post admin requests to the list. They will be ignored.
> Coreaudio-api mailing list (email@hidden)
> Help/Unsubscribe/Update your Subscription:
>
> This email sent to email@hidden
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden