• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: Using an AU directly
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Using an AU directly


  • Subject: Re: Using an AU directly
  • From: Jean-Daniel Dupas <email@hidden>
  • Date: Mon, 7 Sep 2009 11:21:08 +0200


Le 7 sept. 2009 à 11:07, Darrell Gibson a écrit :


Hi All,

Following on from a previous post (http://lists.apple.com/archives/Coreaudio-api/2009/Aug/msg00179.html ).

I am now trying use an AudioUnits directly on its own, without an AUGraph. What I effectively want to do is send audio data into the AudioUnit, let the audio unit process the data and then obtain the processed data. (I just want the data, I don't actually want an audio output.)

In order to do this what I have done is created an instance of the AU and then setup an input render callback that supplies the input data. The problem I have is without an output device to initiate the "pull" my render callback is never called. If I connect an output unit it does start to "pull" but I also get an output, which I do not want. I want to analyze the output, but not listen to it.

Is there away to start a network of AUs that has does not been connected to an output device? By start I mean initiate the "pull".

If not would I have to connect to an output unit, capture the data coming in, but not allow the unit to render the data? Could I do this by setting up a render callback for the output unit, write the input into an AudioBufferList and do not call the AudioUnitRender function? Does this sound reasonable?

I assume I can have an AU connected to another AU and still define a render callback for the last AU? Will this work?

Thanks for any pointers you can offer.

Darrell.


AudioUnit is based on a 'pull' model. You need something to pull the data. Usually, this is done by the Output Unit, but if you don't have an Output unit, I think you have to pull the data yourself calling AudioUnitRender() in a loop and passing the last AudioUnit of your graph as argument.


-- Jean-Daniel




_______________________________________________ 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
References: 
 >Using an AU directly (From: Darrell Gibson <email@hidden>)

  • Prev by Date: Re: Building AudioUnits for Mac OS 10.4 on Snow Leopard
  • Next by Date: Re: Using an AU directly
  • Previous by thread: Using an AU directly
  • Next by thread: Re: Using an AU directly
  • Index(es):
    • Date
    • Thread