diff options
Diffstat (limited to 'gst/audiofx/audiochebband.c')
| -rw-r--r-- | gst/audiofx/audiochebband.c | 29 |
1 files changed, 11 insertions, 18 deletions
diff --git a/gst/audiofx/audiochebband.c b/gst/audiofx/audiochebband.c index bf9c205e..7ecb7956 100644 --- a/gst/audiofx/audiochebband.c +++ b/gst/audiofx/audiochebband.c @@ -34,42 +34,35 @@ /** * SECTION:element-audiochebband - * @short_description: Chebyshev band pass and band reject filter * - * <refsect2> - * <para> * Attenuates all frequencies outside (bandpass) or inside (bandreject) of a frequency * band. The number of poles and the ripple parameter control the rolloff. - * </para> - * <para> + * * This element has the advantage over the windowed sinc bandpass and bandreject filter that it is * much faster and produces almost as good results. It's only disadvantages are the highly * non-linear phase and the slower rolloff compared to a windowed sinc filter with a large kernel. - * </para> - * <para> + * * For type 1 the ripple parameter specifies how much ripple in dB is allowed in the passband, i.e. * some frequencies in the passband will be amplified by that value. A higher ripple value will allow * a faster rolloff. - * </para> - * <para> + * * For type 2 the ripple parameter specifies the stopband attenuation. In the stopband the gain will * be at most this value. A lower ripple value will allow a faster rolloff. - * </para> - * <para> + * * As a special case, a Chebyshev type 1 filter with no ripple is a Butterworth filter. - * </para> - * <para><note> + * + * <note> * Be warned that a too large number of poles can produce noise. The most poles are possible with * a cutoff frequency at a quarter of the sampling rate. - * </note></para> + * </note> + * + * <refsect2> * <title>Example launch line</title> - * <para> - * <programlisting> + * |[ * gst-launch audiotestsrc freq=1500 ! audioconvert ! audiochebband mode=band-pass lower-frequency=1000 upper-frequenc=6000 poles=4 ! audioconvert ! alsasink * gst-launch filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! audiochebband mode=band-reject lower-frequency=1000 upper-frequency=4000 ripple=0.2 ! audioconvert ! alsasink * gst-launch audiotestsrc wave=white-noise ! audioconvert ! audiochebband mode=band-pass lower-frequency=1000 upper-frequency=4000 type=2 ! audioconvert ! alsasink - * </programlisting> - * </para> + * ]| * </refsect2> */ |