• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback


  • Subject: Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback
  • From: Nikolai Collinsky <email@hidden>
  • Date: Sun, 24 Oct 2010 14:07:09 +0100

Thanks Tahome. Unfortunately, that doesn't help; if I change to

NSDictionary *audioSetting = [NSDictionary dictionaryWithObjectsAndKeys:
									  [NSNumber numberWithFloat:44100.0],AVSampleRateKey,
									  [NSNumber numberWithInt:2],AVNumberOfChannelsKey,	//how many channels has original?
									  [NSNumber numberWithInt:16],AVLinearPCMBitDepthKey, //was 16
									  [NSNumber numberWithInt:kAudioFormatLinearPCM], AVFormatIDKey,
									  [NSNumber numberWithBool:NO], AVLinearPCMIsFloatKey,  //was NO
									  [NSNumber numberWithBool:0], AVLinearPCMIsBigEndianKey,
									  [NSNumber numberWithBool:NO], AVLinearPCMIsNonInterleaved,
									  [NSData data], AVChannelLayoutKey, nil];

I still get a freeze for AVAssetReaderTrackOutput, and interruption callback for AVAssetReaderAudioMixOutput.

I'm obviously doing my own floating point processing, and happy to convert back to short int for final output. Also from the documentation:

AVLinearPCMIsFloatKey
A Boolean value that indicates that the audio format is floating point (YES) or fixed point (NO).
Available in iOS 3.0 and later.

I figured the convertor could convert to float for me, and have seen some sensible values in -1.0 to 1.0 range in the debugger; I just can't play them via RemoteIO with processing because of the audio callback interruption issue.

any other ideas?

best
N


On 24 Oct 2010, at 11:55, tahome izwah wrote:

> Last time I checked float audio format wasn't supported on the device.
> You will have to use short int and convert to float in your own code
> if you must use float.
>
> --th
>
> 2010/10/24 Nikolai Collinsky <email@hidden>:
>> I've scratched my head over this for many days, and would now like to request help. I wanted to get floating point samples from any track in the iPod Library, which should be straight forward with new AVAssetReader facilities in iOS 4.1 (I'm working with Xcode 3.2.4, 4.1 SDK, with an iPod Touch at 4.1).
> _______________________________________________
> 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

 _______________________________________________
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

  • Follow-Ups:
    • Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback
      • From: Nikolai Collinsky <email@hidden>
References: 
 >iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback (From: Nikolai Collinsky <email@hidden>)
 >Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback (From: tahome izwah <email@hidden>)

  • Prev by Date: Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback
  • Next by Date: Re: AudioUnits and the MacOS X App Store
  • Previous by thread: Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback
  • Next by thread: Re: iOS 4.1: using AVAssetReader to stream from an audio file interrupts audio callback
  • Index(es):
    • Date
    • Thread