Skip to main content

mod_dptools: detect_silence

About

Pause dialplan execution while waiting for a certain length of silence on the channel. When silence is detected, or when the timeout period has expired, dialplan processing will continue.

Click here to expand Table of Contents

Usage

detect_silence <silence_thresh> <silence_hits> <timeout> [<file>]

Description

This function is similar to the wait_for_silence function except this does not require noise hits before listening for silence

"Silence" is determined by a combination of the <silence_thresh> value and the <silence_hits> value.

  • The silence_thresh value is the silence threshold. The lower the value, the "quieter" the channel must be in order to be considered in a silent state. A larger value allows louder sound received from the endpoint to be treated as silence.
  • The silence_hits value represents the number of consecutive frames received with an "energy level" below the silence_thresh value that must be seen before the channel is considered in a silent state. The higher this value, the longer the channel must be in a "silent" state before silence is detected.
  • The <timeout_ms> value represents the overall time in milliseconds that the wait_for_silence app will attempt to detect silence before ending the wait and moving on to the next dialplan line.
  • <file> is an optional sound file that can be read and analyzed for silence detection.

Dialplan Example

<action application="detect_silence" data="200 15 5000"/>