Open Source C Speech Software

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

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

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.

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.

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.

a tool for segmenting, labeling and transcribing speech

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.

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

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.

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.

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

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

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.

WAV Speech Enhancer can be used to improve the signal to noise ratio of bad quality speech recordings: - Dynamic expansion - Pink noise attenuation - Low frequency noise (50-60Hz) suppression

The SingIt Lyric Displayer is an XMMS plugin which displays formatted lyrics, including id3v2xx lyrics. It consists of the displayer and an integrated editor which allows one to easily insert time stamps, edit the text, and export & strip HTML.

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.

Talkbox is a program wich makes your computer talk "with" you. It has a AI based on ALICE program C and uses Festvial speech engin along with speechd to produce voice synthisis. You input text by typeing there is no support for voice reconition.

Text-to-Speech conversor for Basque and Spanish. It includes linguistic processing and built voices for the languages aforementioned. Its acoustic engine is based on hts_engine and it uses a high quality vocoder called AhoCoder. Developed by Aholab Signal Processing Laboratory: https://aholab.ehu.es/aholab/ http://aholab.ehu.es/ahocoder/

SAA (SSPLab Audio Analyzer) It will be able to separate sources, recognize speech and analyze the auditory scene. It can also synthesize spatialised sounds from mono recording, edit, analyze via spectrogram, filter and re-sample signals.

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

This is a fast C implementation of Arturo Camacho's SWIPE' pitch extraction algorithm. See the project homepage for more about the advantages of the SWIPE' algorithm. swipe-1.0.tar.gz contains the current source, which should compile quite neatly.

Scalable Language API (SLAPI) The most comprehensive architecture for conversational natural-language applications including speech recognition/synthesis, semantics, & machine translation. Used on Android & other mobile app platforms.

To provide basic text-to-speech capability on as many platforms and for as many spoken languages as possible by formant synthesis from an International Phonetic Alphabet representation.

Simple testing tool to generate RTP data packets and send it via netwok interface or save into pcap file. Primarily intended for use with SIPp application to test speech quality with different codecs.