gst-plugins-good  1.20.3
About: GStreamer (Good Plugins) is a library for constructing of graphs of media-handling components. A set of good-quality plug-ins (under LGPL license).
  Fossies Dox: gst-plugins-good-1.20.3.tar.xz  ("unofficial" and yet experimental doxygen-generated source code documentation)  

audiowsincband.c
Go to the documentation of this file.
1/* -*- c-basic-offset: 2 -*-
2 *
3 * GStreamer
4 * Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu>
5 * 2006 Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>
6 * 2007-2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
17 *
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
22 *
23 *
24 * this windowed sinc filter is taken from the freely downloadable DSP book,
25 * "The Scientist and Engineer's Guide to Digital Signal Processing",
26 * chapter 16
27 * available at http://www.dspguide.com/
28 *
29 * For the window functions see
30 * http://en.wikipedia.org/wiki/Window_function
31 */
32
33/**
34 * SECTION:element-audiowsincband
35 * @title: audiowsincband
36 *
37 * Attenuates all frequencies outside (bandpass) or inside (bandreject) of a frequency
38 * band. The length parameter controls the rolloff, the window parameter
39 * controls rolloff and stopband attenuation. The Hamming window provides a faster rolloff but a bit
40 * worse stopband attenuation, the other way around for the Blackman window.
41 *
42 * This element has the advantage over the Chebyshev bandpass and bandreject filter that it has
43 * a much better rolloff when using a larger kernel size and almost linear phase. The only
44 * disadvantage is the much slower execution time with larger kernels.
45 *
46 * ## Example launch line
47 * |[
48 * gst-launch-1.0 audiotestsrc freq=1500 ! audioconvert ! audiowsincband mode=band-pass lower-frequency=3000 upper-frequency=10000 length=501 window=blackman ! audioconvert ! alsasink
49 * 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
50 * gst-launch-1.0 audiotestsrc wave=white-noise ! audioconvert ! audiowsincband mode=band-pass lower-frequency=1000 upper-frequency=2000 length=31 ! audioconvert ! alsasink
51 * ]|
52 *
53 */
54
55#ifdef HAVE_CONFIG_H
56#include "config.h"
57#endif
58
59#include <string.h>
60#include <math.h>
61#include <gst/gst.h>
62#include <gst/audio/gstaudiofilter.h>
63
64#include "audiowsincband.h"
65
67
68#define GST_CAT_DEFAULT gst_gst_audio_wsincband_debug
70
71enum
72{
79};
80
81enum
82{
85};
86
87#define GST_TYPE_AUDIO_WSINC_BAND_MODE (gst_gst_audio_wsincband_mode_get_type ())
88static GType
90{
91 static GType gtype = 0;
92
93 if (gtype == 0) {
94 static const GEnumValue values[] = {
95 {MODE_BAND_PASS, "Band pass (default)",
96 "band-pass"},
97 {MODE_BAND_REJECT, "Band reject",
98 "band-reject"},
99 {0, NULL, NULL}
100 };
101
102 gtype = g_enum_register_static ("GstAudioWSincBandMode", values);
103 }
104 return gtype;
105}
106
107enum
108{
115
116#define GST_TYPE_AUDIO_WSINC_BAND_WINDOW (gst_gst_audio_wsincband_window_get_type ())
117static GType
119{
120 static GType gtype = 0;
121
122 if (gtype == 0) {
123 static const GEnumValue values[] = {
124 {WINDOW_HAMMING, "Hamming window (default)",
125 "hamming"},
126 {WINDOW_BLACKMAN, "Blackman window",
127 "blackman"},
128 {WINDOW_GAUSSIAN, "Gaussian window",
129 "gaussian"},
130 {WINDOW_COSINE, "Cosine window",
131 "cosine"},
132 {WINDOW_HANN, "Hann window",
133 "hann"},
134 {0, NULL, NULL}
135 };
136
137 gtype = g_enum_register_static ("GstAudioWSincBandWindow", values);
138 }
139 return gtype;
140}
141
142#define gst_audio_wsincband_parent_class parent_class
143G_DEFINE_TYPE (GstAudioWSincBand, gst_audio_wsincband,
145GST_ELEMENT_REGISTER_DEFINE (audiowsincband, "audiowsincband",
146 GST_RANK_NONE, GST_TYPE_AUDIO_WSINC_BAND);
147
148static void gst_audio_wsincband_set_property (GObject * object, guint prop_id,
149 const GValue * value, GParamSpec * pspec);
150static void gst_audio_wsincband_get_property (GObject * object, guint prop_id,
151 GValue * value, GParamSpec * pspec);
152static void gst_audio_wsincband_finalize (GObject * object);
153
154static gboolean gst_audio_wsincband_setup (GstAudioFilter * base,
155 const GstAudioInfo * info);
156
157#define POW2(x) (x)*(x)
158
159static void
161{
162 GObjectClass *gobject_class = (GObjectClass *) klass;
163 GstElementClass *gstelement_class = (GstElementClass *) klass;
164 GstAudioFilterClass *filter_class = (GstAudioFilterClass *) klass;
165
166 GST_DEBUG_CATEGORY_INIT (gst_gst_audio_wsincband_debug, "audiowsincband", 0,
167 "Band-pass and Band-reject Windowed sinc filter plugin");
168
169 gobject_class->set_property = gst_audio_wsincband_set_property;
170 gobject_class->get_property = gst_audio_wsincband_get_property;
171 gobject_class->finalize = gst_audio_wsincband_finalize;
172
173 /* FIXME: Don't use the complete possible range but restrict the upper boundary
174 * so automatically generated UIs can use a slider */
175 g_object_class_install_property (gobject_class, PROP_LOWER_FREQUENCY,
176 g_param_spec_float ("lower-frequency", "Lower Frequency",
177 "Cut-off lower frequency (Hz)", 0.0, 100000.0, 0,
178 G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
179 g_object_class_install_property (gobject_class, PROP_UPPER_FREQUENCY,
180 g_param_spec_float ("upper-frequency", "Upper Frequency",
181 "Cut-off upper frequency (Hz)", 0.0, 100000.0, 0,
182 G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
183 g_object_class_install_property (gobject_class, PROP_LENGTH,
184 g_param_spec_int ("length", "Length",
185 "Filter kernel length, will be rounded to the next odd number", 3,
186 256000, 101,
187 G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
188
189 g_object_class_install_property (gobject_class, PROP_MODE,
190 g_param_spec_enum ("mode", "Mode",
191 "Band pass or band reject mode", GST_TYPE_AUDIO_WSINC_BAND_MODE,
193 G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
194
195 g_object_class_install_property (gobject_class, PROP_WINDOW,
196 g_param_spec_enum ("window", "Window",
197 "Window function to use", GST_TYPE_AUDIO_WSINC_BAND_WINDOW,
199 G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
200
201 gst_element_class_set_static_metadata (gstelement_class,
202 "Band pass & band reject filter", "Filter/Effect/Audio",
203 "Band pass and band reject windowed sinc filter",
204 "Thomas Vander Stichele <thomas at apestaart dot org>, "
205 "Steven W. Smith, "
206 "Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>, "
207 "Sebastian Dröge <sebastian.droege@collabora.co.uk>");
208
209 filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_wsincband_setup);
210
211 gst_type_mark_as_plugin_api (GST_TYPE_AUDIO_WSINC_BAND_MODE, 0);
212 gst_type_mark_as_plugin_api (GST_TYPE_AUDIO_WSINC_BAND_WINDOW, 0);
213}
214
215static void
217{
218 self->kernel_length = 101;
219 self->lower_frequency = 0.0;
220 self->upper_frequency = 0.0;
221 self->mode = MODE_BAND_PASS;
222 self->window = WINDOW_HAMMING;
223
224 g_mutex_init (&self->lock);
225}
226
227static void
229 const GstAudioInfo * info)
230{
231 gint i = 0;
232 gdouble sum = 0.0;
233 gint len = 0;
234 gdouble *kernel_lp, *kernel_hp;
235 gdouble w;
236 gdouble *kernel;
237 gint rate, channels;
238
239 len = self->kernel_length;
240
241 if (info) {
242 rate = GST_AUDIO_INFO_RATE (info);
243 channels = GST_AUDIO_INFO_CHANNELS (info);
244 } else {
245 rate = GST_AUDIO_FILTER_RATE (self);
246 channels = GST_AUDIO_FILTER_CHANNELS (self);
247 }
248
249 if (rate == 0) {
250 GST_DEBUG ("rate not set yet");
251 return;
252 }
253
254 if (channels == 0) {
255 GST_DEBUG ("channels not set yet");
256 return;
257 }
258
259 /* Clamp frequencies */
260 self->lower_frequency = CLAMP (self->lower_frequency, 0.0, rate / 2);
261 self->upper_frequency = CLAMP (self->upper_frequency, 0.0, rate / 2);
262
263 if (self->lower_frequency > self->upper_frequency) {
264 gint tmp = self->lower_frequency;
265
266 self->lower_frequency = self->upper_frequency;
267 self->upper_frequency = tmp;
268 }
269
270 GST_DEBUG ("gst_audio_wsincband: initializing filter kernel of length %d "
271 "with lower frequency %.2lf Hz "
272 ", upper frequency %.2lf Hz for mode %s",
273 len, self->lower_frequency, self->upper_frequency,
274 (self->mode == MODE_BAND_PASS) ? "band-pass" : "band-reject");
275
276 /* fill the lp kernel */
277 w = 2 * G_PI * (self->lower_frequency / rate);
278 kernel_lp = g_new (gdouble, len);
279 for (i = 0; i < len; ++i) {
280 if (i == (len - 1) / 2.0)
281 kernel_lp[i] = w;
282 else
283 kernel_lp[i] = sin (w * (i - (len - 1) / 2.0)) / (i - (len - 1) / 2.0);
284
285 /* windowing */
286 switch (self->window) {
287 case WINDOW_HAMMING:
288 kernel_lp[i] *= (0.54 - 0.46 * cos (2 * G_PI * i / (len - 1)));
289 break;
290 case WINDOW_BLACKMAN:
291 kernel_lp[i] *= (0.42 - 0.5 * cos (2 * G_PI * i / (len - 1)) +
292 0.08 * cos (4 * G_PI * i / (len - 1)));
293 break;
294 case WINDOW_GAUSSIAN:
295 kernel_lp[i] *= exp (-0.5 * POW2 (3.0 / len * (2 * i - (len - 1))));
296 break;
297 case WINDOW_COSINE:
298 kernel_lp[i] *= cos (G_PI * i / (len - 1) - G_PI / 2);
299 break;
300 case WINDOW_HANN:
301 kernel_lp[i] *= 0.5 * (1 - cos (2 * G_PI * i / (len - 1)));
302 break;
303 }
304 }
305
306 /* normalize for unity gain at DC */
307 sum = 0.0;
308 for (i = 0; i < len; ++i)
309 sum += kernel_lp[i];
310 for (i = 0; i < len; ++i)
311 kernel_lp[i] /= sum;
312
313 /* fill the hp kernel */
314 w = 2 * G_PI * (self->upper_frequency / rate);
315 kernel_hp = g_new (gdouble, len);
316 for (i = 0; i < len; ++i) {
317 if (i == (len - 1) / 2.0)
318 kernel_hp[i] = w;
319 else
320 kernel_hp[i] = sin (w * (i - (len - 1) / 2.0)) / (i - (len - 1) / 2.0);
321
322 /* Windowing */
323 switch (self->window) {
324 case WINDOW_HAMMING:
325 kernel_hp[i] *= (0.54 - 0.46 * cos (2 * G_PI * i / (len - 1)));
326 break;
327 case WINDOW_BLACKMAN:
328 kernel_hp[i] *= (0.42 - 0.5 * cos (2 * G_PI * i / (len - 1)) +
329 0.08 * cos (4 * G_PI * i / (len - 1)));
330 break;
331 case WINDOW_GAUSSIAN:
332 kernel_hp[i] *= exp (-0.5 * POW2 (3.0 / len * (2 * i - (len - 1))));
333 break;
334 case WINDOW_COSINE:
335 kernel_hp[i] *= cos (G_PI * i / (len - 1) - G_PI / 2);
336 break;
337 case WINDOW_HANN:
338 kernel_hp[i] *= 0.5 * (1 - cos (2 * G_PI * i / (len - 1)));
339 break;
340 }
341 }
342
343 /* normalize for unity gain at DC */
344 sum = 0.0;
345 for (i = 0; i < len; ++i)
346 sum += kernel_hp[i];
347 for (i = 0; i < len; ++i)
348 kernel_hp[i] /= sum;
349
350 /* do spectral inversion to go from lowpass to highpass */
351 for (i = 0; i < len; ++i)
352 kernel_hp[i] = -kernel_hp[i];
353 if (len % 2 == 1) {
354 kernel_hp[(len - 1) / 2] += 1.0;
355 } else {
356 kernel_hp[len / 2 - 1] += 0.5;
357 kernel_hp[len / 2] += 0.5;
358 }
359
360 /* combine the two kernels */
361 kernel = g_new (gdouble, len);
362
363 for (i = 0; i < len; ++i)
364 kernel[i] = kernel_lp[i] + kernel_hp[i];
365
366 /* free the helper kernels */
367 g_free (kernel_lp);
368 g_free (kernel_hp);
369
370 /* do spectral inversion to go from bandreject to bandpass
371 * if specified */
372 if (self->mode == MODE_BAND_PASS) {
373 for (i = 0; i < len; ++i)
374 kernel[i] = -kernel[i];
375 kernel[len / 2] += 1;
376 }
377
379 kernel, self->kernel_length, (len - 1) / 2, info);
380}
381
382/* GstAudioFilter vmethod implementations */
383
384/* get notified of caps and plug in the correct process function */
385static gboolean
386gst_audio_wsincband_setup (GstAudioFilter * base, const GstAudioInfo * info)
387{
389
391
392 return GST_AUDIO_FILTER_CLASS (parent_class)->setup (base, info);
393}
394
395static void
397{
399
400 g_mutex_clear (&self->lock);
401
402 G_OBJECT_CLASS (parent_class)->finalize (object);
403}
404
405static void
406gst_audio_wsincband_set_property (GObject * object, guint prop_id,
407 const GValue * value, GParamSpec * pspec)
408{
410
411 g_return_if_fail (GST_IS_AUDIO_WSINC_BAND (self));
412
413 switch (prop_id) {
414 case PROP_LENGTH:{
415 gint val;
416
417 g_mutex_lock (&self->lock);
418 val = g_value_get_int (value);
419 if (val % 2 == 0)
420 val++;
421
422 if (val != self->kernel_length) {
424 (self));
425 self->kernel_length = val;
427 }
428 g_mutex_unlock (&self->lock);
429 break;
430 }
432 g_mutex_lock (&self->lock);
433 self->lower_frequency = g_value_get_float (value);
435 g_mutex_unlock (&self->lock);
436 break;
438 g_mutex_lock (&self->lock);
439 self->upper_frequency = g_value_get_float (value);
441 g_mutex_unlock (&self->lock);
442 break;
443 case PROP_MODE:
444 g_mutex_lock (&self->lock);
445 self->mode = g_value_get_enum (value);
447 g_mutex_unlock (&self->lock);
448 break;
449 case PROP_WINDOW:
450 g_mutex_lock (&self->lock);
451 self->window = g_value_get_enum (value);
453 g_mutex_unlock (&self->lock);
454 break;
455 default:
456 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
457 break;
458 }
459}
460
461static void
462gst_audio_wsincband_get_property (GObject * object, guint prop_id,
463 GValue * value, GParamSpec * pspec)
464{
466
467 switch (prop_id) {
468 case PROP_LENGTH:
469 g_value_set_int (value, self->kernel_length);
470 break;
472 g_value_set_float (value, self->lower_frequency);
473 break;
475 g_value_set_float (value, self->upper_frequency);
476 break;
477 case PROP_MODE:
478 g_value_set_enum (value, self->mode);
479 break;
480 case PROP_WINDOW:
481 g_value_set_enum (value, self->window);
482 break;
483 default:
484 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
485 break;
486 }
487}
void gst_audio_fx_base_fir_filter_set_kernel(GstAudioFXBaseFIRFilter *self, gdouble *kernel, guint kernel_length, guint64 latency, const GstAudioInfo *info)
void gst_audio_fx_base_fir_filter_push_residue(GstAudioFXBaseFIRFilter *self)
#define GST_TYPE_AUDIO_FX_BASE_FIR_FILTER
#define GST_AUDIO_FX_BASE_FIR_FILTER(obj)
static void gst_audio_wsincband_set_property(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
G_DEFINE_TYPE(GstAudioWSincBand, gst_audio_wsincband,(gst_audio_fx_base_fir_filter_get_type()))
#define POW2(x)
GST_ELEMENT_REGISTER_DEFINE(audiowsincband, "audiowsincband", GST_RANK_NONE,(gst_audio_wsincband_get_type()))
static void gst_audio_wsincband_finalize(GObject *object)
static GType gst_gst_audio_wsincband_mode_get_type(void)
static void gst_audio_wsincband_get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
#define GST_TYPE_AUDIO_WSINC_BAND_WINDOW
static void gst_audio_wsincband_init(GstAudioWSincBand *self)
static GType gst_gst_audio_wsincband_window_get_type(void)
@ WINDOW_GAUSSIAN
@ WINDOW_HAMMING
@ WINDOW_BLACKMAN
@ WINDOW_COSINE
@ WINDOW_HANN
static void gst_audio_wsincband_build_kernel(GstAudioWSincBand *self, const GstAudioInfo *info)
@ PROP_MODE
@ PROP_WINDOW
@ PROP_LOWER_FREQUENCY
@ PROP_UPPER_FREQUENCY
@ PROP_0
@ PROP_LENGTH
static void gst_audio_wsincband_class_init(GstAudioWSincBandClass *klass)
static gboolean gst_audio_wsincband_setup(GstAudioFilter *base, const GstAudioInfo *info)
GST_DEBUG_CATEGORY_STATIC(gst_gst_audio_wsincband_debug)
#define GST_TYPE_AUDIO_WSINC_BAND_MODE
#define GST_CAT_DEFAULT
@ MODE_BAND_PASS
@ MODE_BAND_REJECT
#define GST_IS_AUDIO_WSINC_BAND(obj)
#define GST_TYPE_AUDIO_WSINC_BAND
#define GST_AUDIO_WSINC_BAND(obj)
#define parent_class
Definition: gstsbcparse.c:83