Open Source C Speech Software

eGuideDog project develops free software for the blind. Currently, we focus on WebSpeech, Ekho TTS and WebAnywhere.

SPTK is a suite of speech signal processing tools for UNIX environments, e.g., LPC analysis, PARCOR analysis, LSP analysis, PARCOR synthesis filter, LSP synthesis filter, vector quantization techniques, and other extended versions of them.

Open JTalk is a Japanese text-to-speech synthesis system. This software is released under the Modified BSD license.

Praat is a speech analysis application and source repository for doing phonetics by computer. It was created by Paul Boersma and David Weenink at the University of Amsterdam. The software lets researchers, linguists, clinicians, teachers, and students analyze, synthesize, manipulate, and annotate speech recordings. It supports acoustic inspection through waveforms, spectrograms, pitch tracks, formants, intensity, and related phonetic measurements. Praat also includes scripting tools for automating repetitive analysis, building custom workflows, and processing larger speech datasets. The project is especially useful for academic phonetics, speech science, language documentation, pronunciation research, and publication-quality speech visualization.

moonshine is an open-source automatic speech recognition toolkit optimized for fast and accurate transcription on edge devices and local environments. The project is designed to enable real-time voice applications such as live transcription, voice commands, and embedded speech interfaces without requiring heavy cloud infrastructure. Its architecture emphasizes low latency and flexible input handling, allowing audio streams of varying durations rather than relying on fixed processing windows. Moonshine supports multiple platforms including mobile, desktop, and embedded systems, and provides example projects to accelerate integration into real-world products. The toolkit also includes specialized model variants, including monolingual options that improve accuracy for specific languages. Overall, moonshine serves developers building privacy-conscious, on-device voice interfaces that demand high performance with minimal resource overhead.

hts_engine is software to synthesize speech waveform from HMMs trained by the HMM-based speech synthesis system (HTS). This software is released under the Modified BSD license.

a tool for segmenting, labeling and transcribing speech

Unofficial fork of the GyachE (www.phrozensmoke.com), intended for bug-fixes and further development.

The project provides a ready-to-use interface for the julius CSR engine for a handicapped child which is not able to use the keyboard well. It integrates into X11 and Windows. Find out how you can help: http://simon-listens.org/index.php?support

The Open VXI VoiceXML interpreter is a portable open source library that interprets the VoiceXML dialog markup language. It is designed to serve as a reference for parties interested in understanding how VoiceXML markup might be executed.

Source code from the Research Institute for Signals, Systems and Computational Intelligence http://fich.unl.edu.ar/sinc

Software for speech recognition in English & Polish languages. Basic versions of SkryBot: 1. SkryBot Home Speech (English Language) - https://sourceforge.net/projects/skrybotdomowy/files/ReleasesEnglish/InstalatorSkryBotHomeSpeechDemo-2.6.9.18117.exe/download 2. SkryBot DoMowy (Polish Language) - https://sourceforge.net/projects/skrybotdomowy/files/ReleasesPolish/InstalatorSkryBotDoMowyDemo-2.4.9.18117.exe/download More help: https://sourceforge.net/p/skrybotdomowy/wiki/ Domain advanced versions (Polish Language) 1. SkryBot Prawo - for judicial professionals. 2. SkryBot Administracyjny - for civil and government administration. 3. SkryBot Medycyna Rodzinna - for physicians Professional version of SkryBot (commercial) offers you: 1. Audio conversion and cutting sound files into smaller ones. 2. Searching for words or phrases in sound files (recognized by SkryBot). 3. Editing sound files and automatic cutting off long silence parts in audio file.

A language teaching program and library based on C. It includes sound snippets featuring native speakers. You can create, edit and use various lessons and learn via an optional GTK2 interface.

Winboard 4.5 32-bit is a free Windows accessible Chess program that works automatically with the JAWS or the free NVDA screen reader. It is for the blind, low sighted or those who can not use a mouse. It provides vocal announcements of position changes and other selectable board conditions. Blind players also use a separate "tactile chess board". Winboard 4.5 has full keyboard access to move pieces and run menu items. Partial sighted players use high contrast mode and adjust board, piece, most font sizes and colors. Available languages are English, German, Spanish, Italian, Dutch and Russian. Games may be viewed, modified or saved in standard PGN format. Two Chess engines supply play and grand master strength move analysis. Connect to the Free Internet Chess Server (FICS) and play humans. Modify verbosity in screen reader configurations and in the Winboard "Sound" dialog under the "General" menu. Find all documentation in the "doc" folder under the Winboard directory of your C drive.

A patent-free audio codec designed especially for voice (unlike Vorbis which targets general audio) signals and providing good narrowband and wideband quality. This project is complementary to the Ogg Vorbis codec.

Advanced Speech Signal Analysis library provides a structure to handle various file formats and a variety of analysis functions commonly used in speech processing.

Portable GUI Ogg/Speex/FLAC audio encoder/player that can encode wave file and provides additional functionality such as audiofile tagging, html-album generator, cd-ripping, etc. Targeted to be used on Freebsd, Linux and win32 platforms and the frontends

VoiceCode is an Open Source initiative started by the National Research Council of Canada, to develop a programming by voice toolbox. The aim of the project is to make programming through voice input as easy and productive as with mouse and keyboard. For install, Use subversion, as described in this page: http://sourceforge.net/apps/mediawiki/voicecode/index.php?title=VCode_1_Doc/InstallationManual.

Hidden Markov Model based voice models of Austrian German for the Festival speech synthesis system.

Adds mixed excitation to the hts_engine API

A plugin for Teamspeak3. This plugin allows you to follow a user while he switches through channels. For the love menu just right click any name in the server view.

eXtace is a 3D audio visualization tool (or eye candy depending on how you look at it). eXtace requires ESD (Esound) for its sound input source. It performs a FFT (fast fourier transform) on audio and displays it via various graphical modes.

Arabisc is speaker independent large vocabulary continuous speech recognizer for Arabic language released under GNU license.It is also a collection of open source tools that allows researchers and developers to build speech recognition systems for Arab

Speak Freely is a Cross Platform Internet telephony (Voice Chat) application which provides high quality voice grade audio with GSM and CELP compression and encryption with DES, Blowfish, and IDEA ciphers. Refering to recent news: The maintainers will never add any unwanted extra software in the zip download file but we can only speak for our selves.

AhoTTS Iparrahotsa is the TTS developed at the Aholab Signal Processing Laboratory of the University of the Basque Country (UPV/EHU) for the Lapurdian dialect of Basque. This dialect is spoken at the Northern area of the Basque speaking area (French region). This project was funded by the Euroregion Aquitaine-Euskadi under grant EUSKADI-2012-004.