Apply dynamic equalization to input audio stream.

A description of the accepted options follows.

threshold

Set the detection threshold used to trigger equalization. Threshold detection is using bandpass filter. Default value is 0. Allowed range is from 0 to 100.

dfrequency

Set the detection frequency in Hz used for bandpass filter used to trigger equalization. Default value is 1000 Hz. Allowed range is between 2 and 1000000 Hz.

dqfactor

Set the detection resonance factor for bandpass filter used to trigger equalization. Default value is 1. Allowed range is from 0.001 to 1000.

tfrequency

Set the target frequency of equalization filter. Default value is 1000 Hz. Allowed range is between 2 and 1000000 Hz.

tqfactor

Set the target resonance factor for target equalization filter. Default value is 1. Allowed range is from 0.001 to 1000.

attack

Set the amount of milliseconds the signal from detection has to rise above the detection threshold before equalization starts. Default is 20. Allowed range is between 1 and 2000.

release

Set the amount of milliseconds the signal from detection has to fall below the detection threshold before equalization ends. Default is 200. Allowed range is between 1 and 2000.

ratio

Set the ratio by which the equalization gain is raised. Default is 1. Allowed range is between 0 and 30.

makeup

Set the makeup offset by which the equalization gain is raised. Default is 0. Allowed range is between 0 and 100.

range

Set the max allowed cut/boost amount. Default is 50. Allowed range is from 1 to 200.

mode

Set the mode of filter operation, can be one of the following:

listen

Output only isolated bandpass signal.

cut

Cut frequencies above detection threshold.

boost

Boost frequencies bellow detection threshold.

Default mode is cut.

tftype

Set the type of target filter, can be one of the following:

• bell
• lowshelf
• highshelf

Default type is bell.

direction

Set processing direction relative to threshold.

downward

Boost/Cut if threshold is higher/lower than detected volume.

upward

Boost/Cut if threshold is lower/higher than detected volume.

Default direction is downward.

auto

Automatically gather threshold from detection filter. By default is disabled. This option is useful to detect threshold in certain time frame of input audio stream, in such case option value is changed at runtime.

Available values are:

disabled

Disable using automatically gathered threshold value.

off

Stop picking threshold value.

on

Start picking threshold value.