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UniMRCP 1.7.0 Released

UniMRCP 1.7.0 has been released and can be downloaded from the following location:

The recommended version of the UniMRCP dependencies is:


This release allows to pass profile-based and session attributes to engines. There are minor but valuable fixes and enhancements made in the client and server stacks.

The client application and plugin integration interfaces retain backward compatibility. Everybody is encouraged to upgrade.
The detailed list of changes introduced in this release follows.
APR-toolkit library
  • If NTP has drifted the clock backwards, advance the queue based on the set timeout but not actual time difference. (Issue #257)
MPF library
  • Feature: When tracing is set to a new mode of "3", send tracing logs directly to apt_log() using macro expansion. Thanks @sfgeorge. (Pull request #254)
  • Reset all the left-over variables on mpf_buffer_restart()
MRCP client library
  • Added a new function mrcp_application_session_attribs_set() to the client application interface. The new function allows to set optional session attributes overriding or complimenting some of the profile settings such as SIP username or entire URI and feature tags.
MRCP server library
  • Added a check for RTP settings on server profile registration.
  • While creating a new MRCP channel, make sure associated engine is open and ready to process requests.
  • Reworked profile-based association of MRCP resources and engines to allow specifying optional attributes per profile.
  • Added support for optional session attributes passed from signaling agents down to engines.
MRCPv2 transport library
  • While trying to find an existing client connection, do not observe instances with closed socket. (Issue #259)
  • Limit concurrent/shared use of an MRCPv2 client connection by the configuration parameter max-shared-use-count similarly to the server connection.
Sofia-SIP module (MRCPv2 agent)
  • Do not call nua_bye() and respond to session termination straightaway if nua_handle is used for resource discovery only.
  • In offline mode, respond with SIP 503 Service Unavailable to SIP OPTIONS requests. Thanks @michaelplevy. (Issue #242)
  • Allow disabling the Sofia SIP SDP Offer/Answer Engine Module. Thanks @schlagert. (Issue #248, Pull request #249)
  • Added support for optional session attributes passed from signaling agents down to engines.
  • Optionally extract SIP session call id and user name from SIP INVITE along with feature tags and pass them forward through session generic attributes.
ASR Client application (and library)
  • Add asrclient support for multiple, builtin and remote grammars. Thanks @michaelplevy and @schlagert. (Issue #246)
  • For Windows service, use RegisterServiceCtrlHandlerEx() instead of RegisterServiceCtrlHandler() in order to handle user-defined control cases for offline/online. Thanks @michaelplevy.
  • Added new parameters to default configuration files.
Thank you for using UniMRCP.

Arsen Chaloyan
Author of UniMRCP

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