Voice recognition

Free or open source

• Sphinx
• Julius, so far only with a Japanese language model and acoustic model. Used by Vestec for their Asterisk solution. See also here on asterisk forge.
• ISIP
• HTK - has distribution restrictions
• IBM ViaVoice,see also http://volker.dnsalias.net/linux/speechrec.html, also available as Google cache or Wayback Machine. ViaVoice has software for both desktop and telephony applications.
• http://perlbox.org/: Open source voice recognition for desktop steering
• http://freespeech.sourceforge.net/FreeSpeech/html/
• ZOIP: Text adventure ZORK for Asterisk (with text-to-speech and voice recognition)
• http://zaf.github.com/asterisk-speech-recog/ Speech recognition script for Asterisk that uses Google speech API.

Commercial

• LumenVox - amongst others available for Asterisk 1.4 (a LumenVox patch for 1.2 is also available)
• Nuance (formerly ScanSoft): Professional solution, commercial Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (TTS)))))) and ASR software often used for telephony applications
• Loquendo: Professional solution
• Acculab - Built-in to commercial DSP-based telephony cards
• Lernout & Hauspie - Commercial software often used for telephony and embedded applications
• Microsoft Speech Server - Does ASR and Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (TTS)))))) with support for telephony applications
• Other vendors: IBM, Fonix Speech, Sensory Inc., Verbio, Voice Signal Technologies, Vorero, Utopy
• Asterisk cmd ASR - professional, multilanguage voice recognition for Asterisk based on ASP model
• VoiceXML platforms typically offer Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (TTS)))))) and ASR as part of their ASP, software, or hardware appliance solutions
• Verbio ASR 8.0 - available for Asterisk in Spanish, Portuguese, English, French, Catalonian, Euskera, Gallician, Brazilian and differents kinds of American Spanish
• Vocapia VoxSigma speech-to-text software suite

See also

• Voxforge: Collects transcribed speech for use with Free and Open Source Speech Recognition Engines (on Linux, Windows and Mac)
• Asterisk Generic Speech API provided by res_speech primarily used with LumenVox
• Asterisk AGI and particularly EAGI
• Overview on speech recognition
• Dynamic Neural Networks for speech recognition
• Articles on speechcontrol.com
• Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (((Text-to Speech (TTS)))))): Text-toSpeech solutions
• UniMRCP: MRCP based ASR solution
• Asterisk, UniMRCP, Nuance Voice Recognition