I believe Audio units need 44100 Hz, but I'm not sure about that. Regardless, decoding mp3 with an AudioConverter should not introduce any glitches at that rate - any iOS device should be able to handle that without issues.
The 4096 is the right value for any iOS device. Without seeing your code, I don't know where your glitches are coming from. Are you by any chance reading from disk on the same thread that you're playing audio on, or doing anything else that could cause that thread to block? Hank On Apr 26, 2011, at 9:19 PM, Sasikumar JP wrote: > Hank, > I have tried with by setting "kAudioUnitProperty_MaximumFramesPerSlice" > property as 4096 for Mixer and EQ Audio Units. Now audio playback did not > stop when the device goes to sleep mode. > > But i hear glitches along with Audio. > > I have looked at apple sample code MixerHost. it plays nicely even the device > is in sleep mode. But Apple sample code simply mixes 2 PCM audio files and > play it. > > Where as my application converts the stream mp3 in to PCM using > AudioConverterFillComplexBuffer API in realtime and plays it using AudioUnit. > > Does the Audio Conversion introduce any delay in audio packet generation, > which could leads to the glitches in audio playback (when the device in the > sleep mode)? > > Should i set different sample value(4096) for different hardware (iPod Touch > 2nd/3rd/4th Gen...etc) > > How to derive the number of samples for different Sampling Rate? (As per the > Apple document 4096 samples @ 44.1kHz) > > Thanks > Sasikumar JP > > On 26-Apr-2011, at 8:44 PM, Hank Heijink (Mailinglists) wrote: > >> You're thinking of kAudioUnitProperty_MaximumFramesPerSlice >> (http://developer.apple.com/library/ios/#qa/qa1606/_index.html). You have to >> set that to 4096 frames per slice for every audio unit that's not the >> remoteIO unit. >> >> Hank >> >> On Apr 26, 2011, at 11:05 AM, Gregory Wieber wrote: >> >>> In the iOS docs on audio sessions there's a section on apps becoming >>> background tasks. I don't have them in front of me now, but you have to set >>> a property for buffer size when the app goes into the background for it to >>> work. >>> >>> Sent from my iPhone >>> >>> On Apr 25, 2011, at 9:38 PM, Sasikumar JP <jps...@gmail.com> wrote: >>> >>>> Hi, >>>> I am working on streaming audio player application for iOS. currently i am >>>> experimenting with AudioQueue and AudioUnit for playback. >>>> >>>> Both works fine in the normal condition. But AudioUnit playback stopped >>>> playing when device (ipod touch 2nd gen) goes to sleep mode, where as it >>>> works fine with AudioQueue. >>>> >>>> I have set "kAudioSessionCategory_MediaPlayback" session category for both >>>> cases. I assume this session category should continue the playback even in >>>> sleep mode. >>>> >>>> I am not sure what i am missing here. >>>> >>>> I want to add pan/effects features to my application, so i am trying with >>>> AudioUnit. >>>> >>>> Any help is highly appreciated >>>> >>>> Thanks >>>> Sasikumar JP _______________________________________________ >>>> Do not post admin requests to the list. They will be ignored. >>>> Coreaudio-api mailing list (coreaudio-...@lists.apple.com) >>>> Help/Unsubscribe/Update your Subscription: >>>> http://lists.apple.com/mailman/options/coreaudio-api/gregorywieber%40gmail.com >>>> >>>> This email sent to gregorywie...@gmail.com >>> _______________________________________________ >>> Do not post admin requests to the list. They will be ignored. >>> Coreaudio-api mailing list (coreaudio-...@lists.apple.com) >>> Help/Unsubscribe/Update your Subscription: >>> http://lists.apple.com/mailman/options/coreaudio-api/hank.list%40runbox.com >>> >>> This email sent to hank.l...@runbox.com >>> >> > > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
