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iosaudioaudio-recordingplayback

Record, modify pitch and play back audio in real time on iOS

I just wondering if anyone can explain to me how I would go about recording audio, modifying it (pitch?) and playing it back to the user on iPhone.

I'm not asking for someone to do this for me, just a few hints on how I should go about it. looking through the docs it seems like I should be using AVAudioSession, AVAudioRecorder and AVAudioPlayer (AVFoundation.Framework) for the recording playing parts. Or should I be using the CoreAudio.Framework? and then there is the question regarding modifying the audio.

Solution

  • OpenAL is a library, that supports what you're searching for. And its very popular on the iPhone, so maybe you should take a look on this. i.e. The pitch of an sample is easily changeable with only one command:

    alSourcef(source, AL_PITCH, pitch);

    But I'm not sure, if pitch change is also with the AVFoundation or CoreAudio classes possible - never used them.