Praat

(also the Dutch word for "talk") is a free scientific software program for the analysis of speech in phonetics. It has been designed and continuously developed by Paul Boersma and David Weenink of the University of Amsterdam. It can run on a wide range of operating systems, including various Unix versions, Mac and Microsoft Windows. The program also supports speech synthesis, including articulatory synthesis.

FEATURES:

Speech analysis:
· spectral analysis (spectrograms)
· pitch analysis
· formant analysis
· intensity analysis
· jitter, shimmer, voice breaks
· cochleagram
· excitation pattern
Speech synthesis:
· from pitch, formant, and intensity
· articulatory synthesis
Listening experiments:
· identification and discrimination tests
Labelling and segmentation:
· label intervals and time points on multiple tiers
· use phonetic alphabet
· use sound files up to 2 gigabytes (3 hours)
Speech manipulation:
· change pitch and duration contours
· filtering
Learning algorithms:
· feedforward neural networks
· discrete and stochastic Optimality Theory
Statistics:
· multidimensional scaling
· principal component analysis
· discriminant analysis
Graphics:
· high quality for your articles and thesis
· produce Encapsulated PostScript files
· integrated mathematical and phonetic symbols
Programmability:
· easy programmable scripting language
· communicate with other programs
· (the sendpraat source code)
· create hypertext manuals with sound I/O
Portability:
· machine-independent binary files
· read and write many sound and other file types
Configurability:
· grow or shrink menus
· save prefs for fonts, views, sound devices.