• 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: Datasources and digital audio output
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Datasources and digital audio output


  • Subject: Re: Datasources and digital audio output
  • From: Jeff Moore <email@hidden>
  • Date: Fri, 11 Nov 2005 11:55:10 -0800



On Nov 11, 2005, at 10:50 AM, Derk-Jan Hartman wrote:

I have a G5 now, so i can finally start work on supporting the digital out of the G5.
Can anyone explain the concept of "Datasources" for output devices?
I tried looking in the documentation, but couldn't find anything useful.

The data source control of an output provides a means of telling the hardware which destination, from a set of mutually exclusive choices (analog and digital in the G5 case), to send the data. I'm not sure how to explain it more simply than that.


On the G5, the 2 datasources are presented to the users as two different devices in the Sound PrefPane.

Yes, but the Sound Prefs pane is presenting a greatly simplified view of the devices on the system. It's example should not, in general, be followed by applications that are implementing their own device selection UI.


Selecting one of them changes absolutely 0 to the setup of the device from what I can see.

Incorrect. It has changed the value of the data source selector and has redirected the audio output to the chosen port. I think some of our built-in hardware knows whether or not something is actually plugged into the optical jack, so it may still get sent to the analog output when there isn't anything plugged in. I forget and I don't have a G5 in front of me to check.


I both modes all the lpcm and cac3 streamformats are available. So should I see this as some sort of "preference" ??? What are these "datasources" an abstraction of?

You are making connections where none are implied. The data source and the available formats don't necessarily have anything to do with each other.


--

Jeff Moore
Core Audio
Apple


_______________________________________________ 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
  • Follow-Ups:
    • Re: Datasources and digital audio output
      • From: Derk-Jan Hartman <email@hidden>
References: 
 >Datasources and digital audio output (From: Derk-Jan Hartman <email@hidden>)

  • Prev by Date: Re: Device unplugged, how application should handle the situation?
  • Next by Date: problem setting up AUGraph in java
  • Previous by thread: Re: Datasources and digital audio output
  • Next by thread: Re: Datasources and digital audio output
  • Index(es):
    • Date
    • Thread