Re: IOAudioEngine::clipOutputSamples cannot be called
Re: IOAudioEngine::clipOutputSamples cannot be called
- Subject: Re: IOAudioEngine::clipOutputSamples cannot be called
- From: Jeff Moore <email@hidden>
- Date: Tue, 02 Dec 2008 12:47:39 -0800
The HAL won't actually start doing any IO with your device until it
sees the first time stamp from the driver. This could lead to a
situation where performAudioStart() has been called but there are no
subsequent calls to the kernel trap (and hence to your
clipOutputSamples() method).
Is it possible that you've set your driver up such that it isn't
dropping a time stamp in this case?
On Dec 2, 2008, at 1:58 AM, David Tan wrote:
Hi All,
Actually I’m developing a FireWire audio driver.
As my understanding, the clipOutputSamples() should be called after
the performAudioStart() be called no matter if the DCL program is
running or not.
Is that correct?
BTW, I use iTunes to play music and the progress cannot step
forwards. I think that clipOutputSamples() cannot be called explains
it. Is that correct?
Best Regards,
David Tan,
Software Engineer,
Dextrys Co., Ltd.
From: coreaudio-api-bounces+david.tan=email@hidden [mailto:coreaudio-api-bounces+david.tan=email@hidden
] On Behalf Of David Tan
Sent: Tuesday, December 02, 2008 4:38 PM
To: CoreAudio-API Mailing List
Subject: IOAudioEngine::clipOutputSamples cannot be called
Hi Apple,
I have asked this question two weeks before and Jeff kindly gave me
some confirmation that the overridden of it is feasible.
But unfortunately I’m still blocked at this issue.
Now my question is: is it possibly caused by incorrect setup of
output IOAudioStream?
Although I can see my device on Sound Preference Pane and HALLab
device window, I’m suspicious of something incorrect in it.
BTW, my audio engine creates one input stream and one output stream
respectively.
Thanks a lot!
Best Regards,
David Tan,
Software Engineer,
Dextrys Co., Ltd.
--
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