ssml_validation

Sets the mode to evaluate SSML markup in input text.

Value
  • strict (default) validates the input against the SSML 1.0 Recommendation with Nuance extensions. If validation fails, Vocalizer logs error messages and aborts the synthesis operation with an error.
  • warn validates the input and logs errors, but does not abort the synthesis operation.
  • none skips validation.

DEFAULT: strict

How to set

Shown in precedence order (see Rules of parameter precedence):

Set in a VoiceXML application, using the switts.ssml_validation property in a <property> element.

Set in the voice browser, with switts.ssml_validation using the Vendor-Specific-Parameters header in a SPEAK method.

In the application's session xml in the <speechsynth> section of <sessionparameters>.

Use

Sometimes used.

The "strict" mode is the most robust setting because it ensures agreement between the application and Vocalizer engine. Otherwise Vocalizer tries to handle bad input, which may lead to TTS output that differs from the application intent.