audiowsinclimit: GStreamer Good Plugins 1.0 Plugins Reference Manual

audiowsinclimit

Properties

gint	length	Read / Write
GstAudioWSincLimitMode	mode	Read / Write
GstAudioWSincLimitWindow	window	Read / Write
gfloat	cutoff	Read / Write

Types and Values

struct

GstAudioWSincLimit

Object Hierarchy

    GObject
    ╰── GInitiallyUnowned
        ╰── GstObject
            ╰── GstElement
                ╰── GstBaseTransform
                    ╰── GstAudioFilter
                        ╰── GstAudioFXBaseFIRFilter
                            ╰── GstAudioWSincLimit

Description

Attenuates all frequencies above the cutoff frequency (low-pass) or all frequencies below the cutoff frequency (high-pass). The length parameter controls the rolloff, the window parameter controls rolloff and stopband attenuation. The Hamming window provides a faster rolloff but a bit worse stopband attenuation, the other way around for the Blackman window.

This element has the advantage over the Chebyshev lowpass and highpass filter that it has a much better rolloff when using a larger kernel size and almost linear phase. The only disadvantage is the much slower execution time with larger kernels.

Example launch line

1
2
3

gst-launch-1.0 audiotestsrc freq=1500 ! audioconvert ! audiowsinclimit mode=low-pass cutoff=1000 length=501 ! audioconvert ! alsasink
gst-launch-1.0 filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! audiowsinclimit mode=high-pass cutoff=15000 length=501 ! audioconvert ! alsasink
gst-launch-1.0 audiotestsrc wave=white-noise ! audioconvert ! audiowsinclimit mode=low-pass cutoff=1000 length=10001 window=blackman ! audioconvert ! alsasink

Synopsis

Element Information

plugin	audiofx
author	Thomas Vander Stichele <thomas at apestaart dot org>, Steven W. Smith, Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>, Sebastian Dröge <sebastian.droege@collabora.co.uk>
class	Filter/Effect/Audio

Element Pads

name	sink
direction	sink
presence	always
details	audio/x-raw, format=(string){ F32LE, F64LE }, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], layout=(string)interleaved

name	src
direction	source
presence	always
details	audio/x-raw, format=(string){ F32LE, F64LE }, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ], layout=(string)interleaved

Functions

Types and Values

struct GstAudioWSincLimit

struct GstAudioWSincLimit;

Opaque data structure.

Property Details

The `“length”` property

  “length”                   gint

Filter kernel length, will be rounded to the next odd number.

Flags: Read / Write

Allowed values: [3,256000]

Default value: 101

The `“mode”` property

  “mode”                     GstAudioWSincLimitMode

Low pass or high pass mode.

Flags: Read / Write

Default value: Low pass (default)

The `“window”` property

  “window”                   GstAudioWSincLimitWindow

Window function to use.

Flags: Read / Write

Default value: Hamming window (default)

The `“cutoff”` property

  “cutoff”                   gfloat

Cut-off Frequency (Hz).

Flags: Read / Write

Allowed values: [0,100000]

Default value: 0