Re: choppy audio recording
Re: choppy audio recording
- Subject: Re: choppy audio recording
- From: Jeff Moore <email@hidden>
- Date: Wed, 25 Nov 2009 11:31:01 -0800
I listened at the recording. You can clearly hear that the recording is not just glitching, it is actually repeating itself in small chunks. It also seemed that the glitches were not the same duration or spaced evenly. But it's hard to tell with an MP3 encoded version. The MP3 encoding also really prevents me from analyzing the content of the glitch.
At any rate, the sonic evidence would seem to point toward the hardware device as the source of the problem by virtue of the uneven timing of the glitches. But here are some things to look at:
- Test your app with other hardware. While it seems like this is a hardware issue on the surface, it could be somewhere else in the food chain. Testing with other hardware would be a good way to confirm or deny this.
- Test your hardware with other apps.
- Make sure your app is listening to kAudioDeviceProcessorOverload for when the HAL says that things have gone off the rails.
- Use the IO cycle telemetry window in HALLab (found in /Developer/Applications/Audio) to analyze what your app's IO cycle is up to. This is a good way to look at overloads and other problems and see what caused them. I've posted usage notes about this on this list previously.
On Nov 25, 2009, at 9:52 AM, Simmons, Aaron wrote:
> I am using CoreAudio on Mac OS X 10.5.8 in an application that does lots of short microphone recordings using a USB headset. Normally, the recording is fine. However, after some period of time the recordings become distorted and choppy. The audio quality itself is fine, but it sounds as if the user is speaking through a fan. You can hear an example of what I mean here:
> http://sites.google.com/site/paleozogt/home/choppy-audio
>
> Does anyone have any ideas on where to start with a problem like this?
--
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