PRAAT

1. General

Praat is a toolkit to do phonetics by computer. It has been designed and is continuously developed further by Paul Boersma (University of Amsterdam). And here comes the best bit: it is shareware. A detailed introduction including the manual is available at www.praat.org/. One can run Praat on a wide range of operating systems, including various Unix platforms, Mac and Windows NT. As such it can be used in a fieldwork situation on a laptop. Praat is useful for a wide range of analyses and manipulations.

2. Acoustic analysis

In descriptive studies one regularly encounters intuitive statements on segmental or prosodic phenomena that are not supported by acoustic analysis. That is a pity. In this respect Praat can be a great help. A variety of analyses is available for (speech) signals, including pitch, intensity, formants and spectrograms, spectral balance, etc. When handling uniform datasets, the user can facilitate the repetition of measurement procedures by means of scripts - the scripting possibilities are easy to use, thanks to the extensive Help and a 'History to script' function. The standard user interface includes the Object window, with a Sound object and TextGrid object (= a labelfile) loaded. Displayed below is the interface of a user-defined analysis script for the analysis of the acoustic correlates of lexical stress, taking as input a continuously numbered set of soundfiles.

3. Labeling with Praat

In various degrees of detail, transcriptions of speech form the basis of much linguistic work, ranging from segmentation over word-class labeling to sentence type marking. Praat offers two label types: an IntervalTier consists of labels with for each label a starting point and an end point on the time axis. A PointTier pairs labels to single time points. IPA symbols can be used in both tier types.

Figure 2 exemplifies the use of both types of tiers in a multilevel grid, intended for a corpus study of Kupang Malay intonation.

4. Some other interesting bits

- Praat features PSOLA and LPC resynthesis. This can be useful for research on the perception of prosodic phenomena.
- All objects can be edited as a picture; figure 3 gives an idea of what is possible.
- The Praat-internal ManPages format is a concise markup language. It is convertible into HTML and is particularly useful for using Praat in a teaching context.
- A number of statistical tests, neural networks, articulatory synthesis, and more.

Pros: Wide range of analyses and manipulations, scripting facilities, multilevel transcription with IPA, picture editing, platform independence (fits on a laptop)
Cons: cannot handle long sounds (will be mended very soon)
Current version: I reviewed 3.7 on a Unix platform; 3.8 is coming up, featuring string evaluation
Platform: Unix, Macintosh, Windows 95/NT
Application size: 2.6 Mb (Mac), 2,53 Mb (95/NT version)
Suggested minimum RAM: 32 Mb for 95/NT version; the Macintosh version requires a PowerMac.
Documentation: a detailed (660 pp), searchable manual (also online)
Author: Paul Boersma
Available from: http://fonsg3.let.uva.nl/praat
Review by: Bert Remijsen (remijsen@rullet.LeidenUniv.nl)

 

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