AudIndex - Real-time Audio Indexing Tool

AudIndex is a Windows PC program for quickly adding an index to an audio file. AudIndex will allow you to replay the audio while recording the times (relative to the start of the audio) when keys are pressed. This allows you to quickly locate interesting points in the audio, and may be useful in collecting simple statistics (such as counts of utterances or counts of dysfluencies), or just to create a set of markers useful in cutting up the audio into separate files.

Annotations may be loaded and saved using a simple text format, or saved with the audio in SFS format files.

AudIndex - Real-time Audio Indexing Tool


The program is only available for Windows PCs from

To download the file, right click on the link above and choose "Save Target As". Save the file to your desktop or to a folder on your computer. Then run the file to install the program and to add an entry to your Start Programs menu. Once installed you can delete the downloaded file.


Use File|Open Audio to load an audio file. These should be uncompressed PCM samples in WAV format, or audio and annotations stored in SFS format files.

Use File|Open Index to load any existing annotations in text format. The file format consists of one annotation per line, with the time in seconds followed by a text label.

Use Audio|Play to start playing the audio. While the audio is playing, any alphabetic key strokes are recorded as possible annotations, and added to the display at the appropriate time relative to the start of the audio. You can pause and restart the replay at any time without losing position.

Use File|Save Index or File|Save Index As to save the annotations in text format or into an existing SFS file.

You can select and delete annotations by highlighting them and pressing the delete key.

Long key presses are recorded as pairs of annotations, e.g. "A" ... "/A".

Text files may be loaded into Excel or similar for data processing. Alternatively annotations in SFS format may be processed using scripts written in the SFS scripting language SML.

Annotation File Format

Bug reports

Please send suggestions for improvements and reports of program faults to

Please note that we are unable to provide help with the use of this program.


AudIndex is not public domain software, its intellectual property is owned by Mark Huckvale, University College London. However AudIndex may be used and copied without charge as long as the program remains unmodified and continues to carry this copyright notice. Please contact the author for other licensing arrangements. AudIndex carries no warranty of any kind, you use it at your own risk.

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