Part 4 of this series talked about writing recorded audio data to a file. In this article we will set create a very simple user interface so we can control the audio functions. We are going to add a UILabel control that will display text corresponding to the current state of the application. We’ll also [...]

In Part 3 of this series of articles we created the AudioInputCallback function that does nothing more than log that it is being called. In this article we’ll learn how to create an audio file in the Document directory of the iPhone flash memory and write audio data to the file. First of all we’ll [...]

Version 9a2151 of the iPhone SDK is available from the Apple iPhone Developer web site. This version includes the much awaited Interface Builder tool for building graphical interfaces visually.

In the last article we learned how to open a new audio input queue, allocate some buffers and enqueue the buffers for recording. Now we are going to see an extremely simple audio input callback function and learn how to start recording. 1 2 3 4 5 6 7 8 9 10 11 12 13 [...]

Last time we created the RecordState structure to keep track of the recording state. We also configured the recording parameter to record 8000 samples per second, 16 bit, mono audio. Now we can create the audio output queue with the following call: 1 2 3 4 5 6 7 8 OSStatus status = AudioQueueNewInput( &recordState.dataFormat, [...]