audiofirfilter

audiofirfilter — Generic audio FIR filter with custom filter kernel

Synopsis

struct              GstAudioFIRFilter;

Object Hierarchy

  GObject
   +----GInitiallyUnowned
         +----GstObject
               +----GstElement
                     +----GstBaseTransform
                           +----GstAudioFilter
                                 +----GstAudioFXBaseFIRFilter
                                       +----GstAudioFIRFilter

Properties

  "kernel"                   GValueArray*          : Read / Write
  "latency"                  guint64               : Read / Write

Signals

  "rate-changed"                                   : Run Last

Description

audiofirfilter implements a generic audio FIR filter. Before usage the "kernel" property has to be set to the filter kernel that should be used and the "latency" property has to be set to the latency (in samples) that is introduced by the filter kernel. Setting a latency of n samples will lead to the first n samples being dropped from the output and n samples added to the end.

The filter kernel describes the impulse response of the filter. To calculate the frequency response of the filter you have to calculate the Fourier Transform of the impulse response.

To change the filter kernel whenever the sampling rate changes the "rate-changed" signal can be used. This should be done for most FIR filters as they're depending on the sampling rate.

Example application

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