Posts Tagged ‘Audio’

Exploring iPhone Audio Part 7

In the last article of this series we started looking at iPhone audio playback. This time we are going to see how to actually play an audio file that our applicaiton has recorded. The startPlayback method sets everything up for audio playback and starts the playback process. 1 2 3 4 5 6 7 8 [...]

Exploring iPhone Audio Part 6

In Part 5 of this series we added a simple user interface to control the audio recording process. A UILabel was added to display the status. Also two buttons were added to control both recording and playback. Up to this point we have only discussed recording audio. This article will begin to see how to [...]

Exploring iPhone Audio Part 5

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 [...]

Exploring iPhone Audio Part 4

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 [...]

New iPhone SDK Available for Download

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.

Exploring iPhone Audio Part 3

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 [...]

Exploring iPhone Audio Part 2

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, [...]

Exploring iPhone Audio Part 1

The iPhone has the ability to record and playback audio in various formats. This functionality has uses in a multitude of different applications. You could create a simple audio clip recording and playback application or a full blown audio conferencing system or software to record and automatically upload audio clips to a blog just to [...]