swirec_waveform_speech_thresh
Removes line noise from audio recordings.
Value |
Float: 0.0–100.0. Specifies a percentage of the maximum amplitude inside a waveform to be used as threshold for detecting speech. |
Default |
10 (percent) |
How to set |
Shown in precedence order (see Rules of parameter precedence): Set in the browser, using the Vendor-Specific-Parameters header in a RECOGNIZE or SET-PARAMS method. In a parameter grammar. In Management Station set on the Nuance recognition service. If not using Management Station, set in a Recognizer configuration file (User-nrsxx.xml). |
Usage |
Occasionally used when tuning whisper transfer applications to remove line noise from audio recordings. |
Performance |
If you set this parameter, test the results thoroughly. Otherwise, if the setting is too high, you will remove caller speech from the waveform. |
Use this parameter when implementing whisper transfer features (also known as store-and-forward) where audio recordings are captured and then played to human agents. It helps to distinguish between silence and speech in the waveform. The threshold equates a percentage of the loudest sounds with silence (or low volume noise).
Browsers usually set this parameter in a RECOGNIZE request, and the parameter automatically reverts to the previous value after the recognition event. (Alternatively, browsers can use the SET-PARAMS method. See Configuring Recognizer with the browser.)
Vendor-Specific-Parameters: swirec_waveform_speech_thresh=100
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