How do you get the sampling rate of an AudioFileID?

Question

It is easy in iOS to get the number of bytes in a loaded .wav file:

UInt64 dataSize = 0;  // dataSize
UInt32 ps = sizeof(UInt64); // property size
if( AudioFileGetProperty(fileId, kAudioFilePropertyAudioDataByteCount, &ps, &dataSize) )
  puts( "error retriving data chunk size" );
return dataSize ;

But in the documentation I cannot seem to find any information on how to determine the sampling rate of a PCM wave file.

score 6 · Accepted Answer · edited May 23 '17 at 11:53

6

I found the answer using AudioStreamBasicDescription. All you have to do is:

UInt32 getAudioDataSamplingRate( AudioFileID fileId )
{
  AudioStreamBasicDescription bsd;
  UInt32 ps = sizeof(AudioStreamBasicDescription) ;
  if( AudioFileGetProperty(fileId, 
      kAudioFilePropertyDataFormat, &ps, &bsd) )
    puts( "error retriving af basic description" );
  return bsd.mSampleRate ;
}

edited May 23 '17 at 11:53

Community

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answered Dec 19 '12 at 01:18

bobobobo

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How do you get the sampling rate of an AudioFileID?

1 Answers1