audiowsincband

audiowsincband — Band pass and band reject windowed sinc filter

Properties

gfloat lower-frequency Read / Write
gfloat upper-frequency Read / Write
GstAudioWSincBandMode mode Read / Write
GstAudioWSincBandWindow window Read / Write
gint length Read / Write

Types and Values

Object Hierarchy

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

Description

Attenuates all frequencies outside (bandpass) or inside (bandreject) of a frequency band. 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 bandpass and bandreject 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

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gst-launch-1.0 audiotestsrc freq=1500 ! audioconvert ! audiosincband mode=band-pass lower-frequency=3000 upper-frequency=10000 length=501 window=blackman ! audioconvert ! alsasink
gst-launch-1.0 filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! audiowsincband mode=band-reject lower-frequency=59 upper-frequency=61 length=10001 window=hamming ! audioconvert ! alsasink
gst-launch-1.0 audiotestsrc wave=white-noise ! audioconvert ! audiowsincband mode=band-pass lower-frequency=1000 upper-frequency=2000 length=31 ! 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 GstAudioWSincBand

struct GstAudioWSincBand;

Opaque data structure.

Property Details

The “lower-frequency” property

  “lower-frequency”          gfloat

Cut-off lower frequency (Hz).

Flags: Read / Write

Allowed values: [0,100000]

Default value: 0


The “upper-frequency” property

  “upper-frequency”          gfloat

Cut-off upper frequency (Hz).

Flags: Read / Write

Allowed values: [0,100000]

Default value: 0


The “mode” property

  “mode”                     GstAudioWSincBandMode

Band pass or band reject mode.

Flags: Read / Write

Default value: Band pass (default)


The “window” property

  “window”                   GstAudioWSincBandWindow

Window function to use.

Flags: Read / Write

Default value: Hamming window (default)


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