Maria-Gabriella DI BENEDETTO

The xkl project


About xkl

The goal of this joint research project between the Massachusetts Institute of Technology and Sapienza University of Rome is to make modern a comprehensive set of tools for the analysis and synthesis of speech, originally developed by Dennis Klatt. The project will offer the speech research community the possibility of using a superior tool that provides extremely high-quality spectrograms and the possibility to extract, plot, and analyze in a very straightforward manner the spectrum of a particular signal window (spectrum slice) at any instant of time along the time axis. These features are relevant for any study that requires measuring - with high precision - acoustic parameters in the frequency domain. This is particularly true for the analysis of vowels, that requires to estimate formant frequencies with a precision of a few Hz.
Different versions of the software have been used in the last 40 years by several research groups around the world, originally on VAX machines, and more recently on Linux/Unix machines. The project will make xkl available on all major modern Operative Systems: Windows, Linux, MacOs. Another objective is to port the user interface to modern UI libraries, such as GTK.

Bibliography of resources

D. Klatt, “The new MIT Speechvax computer facility,” Speech Communication Group Working Papers IV, (1984).
D. Klatt, “KLSpec documentation,” excerpt of unpublished material (1988).
L. De Nardis, M.-G. Di Benedetto, J.-Y. Choi and S. Shattuck-Hufnagel, "xkl: A legacy software for detailed acoustic analysis of speech made modern," SoftwareX, Volume 23, Article ID 101492, July 2023. DOI: 10.1016/j.softx.2023.101492.
Speech groups making use of xkl in the last 10 years
This is a partial list based on published material. If you use xkl and do not find yourself in the list, please email us at xkl@uniroma1.it.

How to obtain xkl

The xkl software is released under a GNU General Public License v2.0 (GPL-2.0): you can download it from its repository.
Please refer to the LICENSE.txt file in the repository for a copy of the license.
Companies interested in licensing the software under an exception to the GPL-2.0 license can contact the MIT Technology Licensing Office:

MIT Technology Licensing Office 255 Main Street
Cambridge, MA 02142
Tel.: 617-253-6966
Email: software-licenses@mit.edu.