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PocketSphinx Plugin Available

I would like to announce the availability of PocketSphinx ASR plugin for UniMRCP server.

PocketSphinx UniMRCP server can be used with an MRCP compliant client, which supports JSGF grammar.
Currently supported ASR features are as follows:

  • STOP
  • Noinput-Timeout
  • Recognition-Timeout
  • Completion-Cause
  • Completion-Reason
  • Save-Waveform
Grammar: JSGF

For the instructions on how to build and configure PocketSphinx with UniMRCP refer to

Please note, everything is working now, nevertheless this is basic availability only.
I have mostly tested the integrated solution in the following setup
SipPhone -> FreeSWITCH/UniMRCPClient -> UniMRCPServer/PocketSphinx

However it requires further testing in different environments from different speakers, e.t.c.
In other words, your feedback is welcome.

Arsen Chaloyan
The author of UniMRCP

UniMRCP 0.6.0 Released

UniMRCP 0.6.0 (r930) has been released and now is available for download.

Source Distribution

Windows Installer

Windows SDK Installer

Windows Installer has been built using
- APR-1.2.12
- Sofia-SIP-1.12.10 + patch submitted to issue-25
- Visual Studio 2005 (release build)

This is a bug fix release, which contains mostly backward compatible minor API changes.

Changes since previous release 0.5.0 (r828) include:
- Modifications on MRCP headers (Patrick, issue-17)
- Fixed crash of client stack in case of error, when answer contains no SDP
- NAT related enhancements (Garmt, issue-12)
- Enhancements of prosody-volume and prosody-rate params (Bayram, issue-18)
- Fixed string tables of MRCP headers
- Fixed processing of DEFINE-LEXICON request (Mahmoud)
- Fixed processing of consecutive SPEAK and STOP requests (Mahmoud, issue-23)
- Added support for resource discovery (SIP OPTIONS and RTSP DESCRIBE) in server stack (Bayram, issue-19)
- Fixed potential dead lock in MPF layer
- Added CSeq header field in RTSP Announce event generated by server (dbansal, issue-21)
- Enhanced MPF layer to avoid additional transformations when possible (virtualson)
- Reworked RTSP client stack, fixed interoperability with Acapela MRCPv1 server (Garik, issue-22)
- Added resource discovery API to client stack (chaojenh, issue-24)
- Fixed crash on Ubuntu 64bit (Chaitanya)
- Fixed sporadic crash, while referencing dangling pointer in network client/server stacks (Garik)
- Fixed file handle leak in demo synthesizer plugin
- Modified the logger to be able to create and use the same singleton object in core and plugins (Garmt)
- Fixed several valgrind warnings related to memory initialization and usage

Thanks for using UniMRCP.
Arsen Chaloyan

Project Ecosystem

I would like to present the ecosystem of the project I thought about
I used to focus primary on the software development, which is
definitely crucial task towards successful project, but still is not
enough. I want to establish an ecosystem which will "work" for all of
The key components are:

1. Community
The role of community in an open source project development is
evidence. I have been trying to build robust community around the
project. The community is not so big and active at the moment, but at
least it keeps growing. I really welcome and appreciate everybody's

2. Sponsorship
Sponsorship ensures the health, sustainability and encourages growth
of the project

3. Partnership
I'm looking forward for technology related partnership in order to
deliver complete, seamlessly integrated and carefully tested

4. Services
Commercial support packages insure the successful deployment of the
projects you develop.
Custom development options are also available.

This is just the way I see the project can be further evolved.
Actually nothing is going to be changed dramatically. Meantime please
feel free to discuss any suggestions and thoughts you may have.

Arsen Chaloyan.
The creator of UniMRCP.

Cepstral MRCP Server

I would like to introduce Cepstral MRCP server as the primary UniMRCP
based solution.

I want Cepstral to be recognized as the main contributor and sponsor
of UniMRCP project.
Cepstral offers its TTS voices via MRCP using open source UniMRCP

Learn more about the solution:

Also read the press release about successful interop of Cepstral's TTS
voices, Aculab's Prosody platform and UniMRCP between:

Arsen Chaloyan
The creator of UniMRCP.

LumenVox MRCPv2 Interop

I would like to announce the successful interoperability between UniMRCP client and LumenVox ASR MRCPv2 server. This is the follow up to the successful MRCPv1 interoperability.

UniMRCP client stack can be used as a building block to provide connectivity to LumenVox MRCPv1 and/or MRCPv2 servers.
Please check out the Wiki page dedicated to the LumenVox interoperability.

It provides typical configurations and sample network captures. You may also add comments and share your experience there.

LumenVox - Automatic Speech Recognition Vendor (www.lumenvox.com)
UniMRCP - Open Source MRCP Project (www.unimrcp.org)


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