AudioServerPlugIn / kAudioDevicePropertyStreams
AudioServerPlugIn / kAudioDevicePropertyStreams
- Subject: AudioServerPlugIn / kAudioDevicePropertyStreams
- From: Steven Toth <email@hidden>
- Date: Tue, 25 Nov 2014 13:12:29 -0500
(First time poster)
Hello all.
I think I've misunderstood something related to Audio Server Plugins,
hopefully someone with more experience can comment. (OSX 10.9 or
10.10).
I'm writing a userspace driver that exposes multiple independently
operated stereo audio streams (LPCM 44.1). The requirement is that
each audio stream is selectable as a valid audio input via a typical
AVFoundation application, run independently and deliver its own PCM
samples without any impact on other 'streams' within the device.
In other words, a device that can have none-or-more of its streams
running, while other streams within the same device are idle. I
thought CoreAudio allowed that, by exposing N x streams. I think I'm
wrong.
Evidence tells me that the APIs (Eg. StartIO) have no concept of a
single stream running on its own. The entire Device is started and
expected to deliver samples on each stream, in fact I see this during
testing. Calls to DoIOOperation for all exposed streams within the
same Device are received.
If my initial design assumptions are incorrect, what's the preferred
way to achieve my goal?
Perhaps create multiple .driver binaries, each with their own UUID and
have coreaudiod load each like its own independent driver?
Attempts to register multiple plugin uuids in the .driver plist array,
to instruct coreaudiod to register multiple devices from a single
.driver, result in only the first device being created. Pity.
I'd welcome feedback on this. Thanks,
- Steve
--
Steven Toth - Kernel Labs
http://www.kernellabs.com
_______________________________________________
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