My app records two audio files one by one using AVAudioRecorder with audio parameters:
NSDictionary *outputSettings = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInt: kAudioFormatMPEG4AAC], AVFormatIDKey,
[NSNumber numberWithFloat:44100.0], AVSampleRateKey,
[NSNumber numberWithInt:1], AVNumberOfChannelsKey,
[NSNumber numberWithInt:AVAudioQualityMin], AVEncoderAudioQualityKey,
[NSNumber numberWithInt:16],AVEncoderBitDepthHintKey,
[NSNumber numberWithInt:128000], AVEncoderBitRateKey,
nil];
I need append file2 at the end of file1. I'm using solution like there (appending two audio files by creating a AVMutableCompositionTrack after adding the two files and exporting the composition using exportAsynchronouslyWithCompletionHandler:
method of AVAssetExportSession).
It works, but I have two input files 128kbs 44.1kHz 16bit mono, and output file format is: 219.4kbs 44.1kHz 16bit stereo.
Is any way to configure output audio file parameters for AVAssetExportSession?