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-rw-r--r--gst/filter/gstbpwsinc.c28
-rw-r--r--gst/filter/gstbpwsinc.h3
-rw-r--r--gst/filter/gstlpwsinc.c26
-rw-r--r--gst/filter/gstlpwsinc.h3
4 files changed, 57 insertions, 3 deletions
diff --git a/gst/filter/gstbpwsinc.c b/gst/filter/gstbpwsinc.c
index d9690b6c..f86de8d0 100644
--- a/gst/filter/gstbpwsinc.c
+++ b/gst/filter/gstbpwsinc.c
@@ -31,6 +31,30 @@
* is probably the bottleneck
* - Maybe allow cascading the filter to get a better stopband attenuation.
* Can be done by convolving a filter kernel with itself
+ * - Drop the first kernel_length/2 samples and append the same number of
+ * samples on EOS as the first few samples are essentialy zero.
+ */
+
+/**
+ * SECTION:element-bpwsinc
+ * @short_description: Windowed Sinc band pass and band reject filter
+ *
+ * <refsect2>
+ * <para>
+ * 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.
+ * </para>
+ * <title>Example launch line</title>
+ * <para>
+ * <programlisting>
+ * gst-launch audiotestsrc freq=1500 ! audioconvert ! bpwsinc mode=band-pass lower-frequency=3000 upper-frequency=10000 length=501 window=blackman ! audioconvert ! alsasink
+ * gst-launch filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! bpwsinc mode=band-reject lower-frequency=59 upper-frequency=61 length=10001 window=hamming ! audioconvert ! alsasink
+ * gst-launch audiotestsrc wave=white-noise ! audioconvert ! bpwsinc mode=band-pass lower-frequency=1000 upper-frequency=2000 length=31 ! audioconvert ! alsasink
+ * </programlisting>
+ * </para>
+ * </refsect2>
*/
#ifdef HAVE_CONFIG_H
@@ -49,7 +73,7 @@
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
static const GstElementDetails bpwsinc_details =
-GST_ELEMENT_DETAILS ("Band-pass Windowed sinc filter",
+GST_ELEMENT_DETAILS ("Band-pass and Band-reject Windowed sinc filter",
"Filter/Effect/Audio",
"Band-pass Windowed sinc filter",
"Thomas <thomas@apestaart.org>, "
@@ -134,7 +158,7 @@ gst_bpwsinc_window_get_type (void)
" channels = (int) [ 1, MAX ] "
#define DEBUG_INIT(bla) \
- GST_DEBUG_CATEGORY_INIT (gst_bpwsinc_debug, "bpwsinc", 0, "Band-pass Windowed sinc filter plugin");
+ GST_DEBUG_CATEGORY_INIT (gst_bpwsinc_debug, "bpwsinc", 0, "Band-pass and Band-reject Windowed sinc filter plugin");
GST_BOILERPLATE_FULL (GstBPWSinc, gst_bpwsinc, GstAudioFilter,
GST_TYPE_AUDIO_FILTER, DEBUG_INIT);
diff --git a/gst/filter/gstbpwsinc.h b/gst/filter/gstbpwsinc.h
index 537c2f6d..7d9c06ba 100644
--- a/gst/filter/gstbpwsinc.h
+++ b/gst/filter/gstbpwsinc.h
@@ -60,6 +60,7 @@ typedef void (*GstBPWSincProcessFunc) (GstBPWSinc *, guint8 *, guint8 *, guint);
struct _GstBPWSinc {
GstAudioFilter element;
+ /* < private > */
GstBPWSincProcessFunc process;
gint mode;
@@ -76,6 +77,8 @@ struct _GstBPWSincClass {
GstAudioFilterClass parent_class;
};
+GType gst_bpwsinc_get_type (void);
+
G_END_DECLS
#endif /* __GST_BPWSINC_H__ */
diff --git a/gst/filter/gstlpwsinc.c b/gst/filter/gstlpwsinc.c
index 50d0c0f9..c8b7beb2 100644
--- a/gst/filter/gstlpwsinc.c
+++ b/gst/filter/gstlpwsinc.c
@@ -30,7 +30,31 @@
* when using FFT convolution as currently the convolution itself
* is probably the bottleneck
* - Maybe allow cascading the filter to get a better stopband attenuation.
- * Can be done by convolving a filter kernel with itself.
+ * Can be done by convolving a filter kernel with itself
+ * - Drop the first kernel_length/2 samples and append the same number of
+ * samples on EOS as the first few samples are essentialy zero.
+ */
+
+/**
+ * SECTION:element-lpwsinc
+ * @short_description: Windows Sinc low pass and high pass filter
+ *
+ * <refsect2>
+ * <para>
+ * 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.
+ * </para>
+ * <title>Example launch line</title>
+ * <para>
+ * <programlisting>
+ * gst-launch audiotestsrc freq=1500 ! audioconvert ! lpwsinc mode=low-pass frequency=1000 length=501 ! audioconvert ! alsasink
+ * gst-launch filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! lpwsinc mode=high-pass frequency=15000 length=501 ! audioconvert ! alsasink
+ * gst-launch audiotestsrc wave=white-noise ! audioconvert ! lpwsinc mode=low-pass frequency=1000 length=10001 window=blackman ! audioconvert ! alsasink
+ * </programlisting>
+ * </para>
+ * </refsect2>
*/
#ifdef HAVE_CONFIG_H
diff --git a/gst/filter/gstlpwsinc.h b/gst/filter/gstlpwsinc.h
index 599bef84..8a8cd475 100644
--- a/gst/filter/gstlpwsinc.h
+++ b/gst/filter/gstlpwsinc.h
@@ -60,6 +60,7 @@ typedef void (*GstLPWSincProcessFunc) (GstLPWSinc *, guint8 *, guint8 *, guint);
struct _GstLPWSinc {
GstAudioFilter element;
+ /* < private > */
GstLPWSincProcessFunc process;
gint mode;
@@ -76,6 +77,8 @@ struct _GstLPWSincClass {
GstAudioFilterClass parent_class;
};
+GType gst_lpwsinc_get_type (void);
+
G_END_DECLS
#endif /* __GST_LPWSINC_H__ */