Using a microphone

The way to input sound data from a microphone or other audio input device is similar to the sound output considered earlier, with small changes:

1. Add a sound stream object and function for the audio input to the testApp class declaration as follows:

   ofSoundStream soundStream;
   
   void audioReceived( float *input, int bufferSize, int nChannels );

2. At the end of the testApp::setup() function definition, add the following:

   soundStream.setup( this, 0, 1, 44100, 512, 4 );

   Here, this is a pointer to our testApp object which will receive the microphone's sound data by calling our testApp::audioReceived function.

   Subsequently, 0 is the number of output channels (hence, no output), 1 is the number of input channels (hence, mono input), 44100 is a sample rate, that is, the received number of audio samples per second.

   The last two parameters 512 and 4 are the size of the buffer for audio samples and the number of buffers.

3. Add function definition as follows:

   void testApp::audioReceived(
         ...