Recognition methods for speech and DTMF input

Whether you’re using Mix.nlu to recognize the caller’s request or response, a Nuance Recognizer speech grammar (.grxml or .gram), DTMF, or a combination, VoiceXML Connector converts this into a <grammar> tag for your application. Mix.dialog provides the flexibility to handle different combinations of models and grammars, at any question and answer nodes in your dialog design. For example, you might use:

  • DTMF with Mix ASR/NLU resources (default methods for intent and entity recognition)
  • Nuance Recognizer speech grammars (NR grammars) for directed dialog, without support for intent switching, to recognize and parse:
    • entity in focus and commands
    • confirmation
  • NR grammars and DTMF
  • DTMF only

This table shows what to configure (if anything) to enable intent recognition, entity collection and confirmation, and command handling, for these use cases.

Links to relevant configuration topics for common use cases
Scenario Example use cases Enabling for entity collection and confirmation Command handling
ASR/NLU models only NLU collection (intent and entities) Default, no actions required. Commands must be part of the NLU model. See Configure global commands.
ASR/NLU models, and DTMF Menu-type collection, or simple input See Enabling DTMF input. Speech commands must be part of the NLU model.
DTMF mappings can be specified in Mix.dialog, or through an external DTMF grammar.
NR grammar only Alphanumeric collection, or complex speech-only recognition See Enabling Nuance Recognizer grammars. Speech commands must be defined in an external grammar, and also configured in Mix.dialog.
NR grammar, and DTMF Collecting strings of digits, or reusing grammars from an existing IVR project See Enabling Nuance Recognizer grammars and Enabling DTMF input. Speech commands must be defined in an external grammar.
DTMF mappings can be specified in Mix.dialog, or through an external DTMF grammar.
DTMF only Language selection See Enabling DTMF input. DTMF mappings can be specified directly in Mix.dialog, or through an external DTMF grammar.

The Grammars tab of the NLU resource panel allows you to export a grammar specification document, to help design and manage external referenced grammars.