swirec_waveform_begin_silence
How much silence is kept at the start of a collected utterance.
Value |
Integer: 0–INT_MAX. |
Default |
0 (milliseconds) |
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 for whisper-transfer applications to remove unnecessary silence in captured audio recordings. |
Performance |
Removing silence shortens the playback time needed to play the audio waveform to a human administrator, but removing too much silence can make the waveform incomprehensible to the administrator. |
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 specifies the duration of leading silence (before the begin-of-speech) in the returned waveform.
This parameter is intended to reduce silence, but it can also increase silence at the beginning of the waveform. If the amount of silence at the beginning of the endpointed waveform is less than the value of swirec_waveform_begin_silence, then the beginning of the returned waveform will be padded with digital silence (linear 0) to satisfy the specified value.
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_begin_silence=100
Related parameters