> On Apr 18, 2018, at 2:25 PM, Kenny Leung <[email protected]> wrote:
> 
> Hi Patrick.
> 
> I’m trying to write my own hi-res audio player. I’ve already been successful 
> in playing a 24/192kHz audio file on both iOS and macOS using code based on 
> what is written here: 
> https://developer.apple.com/library/content/documentation/MusicAudio/Conceptual/AudioQueueProgrammingGuide/AQPlayback/PlayingAudio.html
>  
> <https://developer.apple.com/library/content/documentation/MusicAudio/Conceptual/AudioQueueProgrammingGuide/AQPlayback/PlayingAudio.html>
> 
> However, the CoreAudio system automatically converts the sample rate 
> internally to whatever the output rate is set to (via Audio Midi Setup on 
> Mac, and some unknown method on iOS).
> 
> On iOS, you can set AVAudioSession.sampleRate, but output still won’t go 
> higher than 48kHz.
> 
> I’m using an XDuoo XD-05 (http://www.xduoo.com/xduoo/En/ProductView.Asp?ID=17 
> <http://www.xduoo.com/xduoo/En/ProductView.Asp?ID=17>) with a display, so it 
> tells me what the phone is outputting. I can use Onkyo player to play at 
> 24/192kHz, but I can’t get my own app to play at any more than 48kHz. Sample 
> rate conversion is precisely the thing I am trying to get away from.

Does the XDuoo shows up as an output device in OSX? Specifically in the Sound 
system preferences? 

> 
> Thanks.
> 
> -Kenny
> 
> 
>> On Apr 18, 2018, at 12:12 PM, Patrick Cusack <[email protected] 
>> <mailto:[email protected]>> wrote:
>> 
>> Your output device is going to determine your sample rate. Any audio you 
>> play is going to be float so 24 bit isn’t a consideration as you will 
>> convert the 24bit audio to float. As for your 192kHz audio, you will either 
>> need to play it out of 192kHz device or perform sample rate conversion in 
>> your audio graph.
>> 
>> This stack overflow listing discusses handling sample rate conversion:
>> 
>> https://stackoverflow.com/questions/6610958/os-x-ios-sample-rate-conversion-for-a-buffer-using-audioconverterfillcomplex
>>  
>> <https://stackoverflow.com/questions/6610958/os-x-ios-sample-rate-conversion-for-a-buffer-using-audioconverterfillcomplex>
>> 
>> 
>> 
>> 
> 

 _______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list      ([email protected])
Help/Unsubscribe/Update your Subscription:
https://lists.apple.com/mailman/options/coreaudio-api/archive%40mail-archive.com

This email sent to [email protected]

Reply via email to