gstreamer/gst/audiotestsrc/gstaudiotestsrc.h
Kipp Cannon 620391b300 audiotestsrc: Add support for generating gaussian white noise
This patch adds support for stationary white Gaussian noise.
The Box-Muller algorithm is used to generate pairs of independent
normally-distributed random numbers.

Fixes bug #586519.
2009-06-21 12:29:03 +02:00

142 lines
4.7 KiB
C

/* GStreamer
* Copyright (C) 2005 Stefan Kost <ensonic@users.sf.net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_AUDIO_TEST_SRC_H__
#define __GST_AUDIO_TEST_SRC_H__
#include <gst/gst.h>
#include <gst/base/gstbasesrc.h>
G_BEGIN_DECLS
#define GST_TYPE_AUDIO_TEST_SRC \
(gst_audio_test_src_get_type())
#define GST_AUDIO_TEST_SRC(obj) \
(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AUDIO_TEST_SRC,GstAudioTestSrc))
#define GST_AUDIO_TEST_SRC_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AUDIO_TEST_SRC,GstAudioTestSrcClass))
#define GST_IS_AUDIO_TEST_SRC(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AUDIO_TEST_SRC))
#define GST_IS_AUDIO_TEST_SRC_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AUDIO_TEST_SRC))
/**
* GstAudioTestSrcWave:
* @GST_AUDIO_TEST_SRC_WAVE_SINE: a sine wave
* @GST_AUDIO_TEST_SRC_WAVE_SQUARE: a square wave
* @GST_AUDIO_TEST_SRC_WAVE_SAW: a saw wave
* @GST_AUDIO_TEST_SRC_WAVE_TRIANGLE: a tringle wave
* @GST_AUDIO_TEST_SRC_WAVE_SILENCE: silence
* @GST_AUDIO_TEST_SRC_WAVE_WHITE_NOISE: white uniform noise
* @GST_AUDIO_TEST_SRC_WAVE_PINK_NOISE: pink noise
* @GST_AUDIO_TEST_SRC_WAVE_SINE_TAB: sine wave using a table
* @GST_AUDIO_TEST_SRC_WAVE_TICKS: periodic ticks
* @GST_AUDIO_TEST_SRC_WAVE_GAUSSIAN_WHITE_NOISE: white (zero mean) Gaussian noise; volume sets the standard deviation of the noise in units of the range of values of the sample type, e.g. volume=0.1 produces noise with a standard deviation of 0.1*32767=3277 with 16-bit integer samples, or 0.1*1.0=0.1 with floating-point samples.
*
* Different types of supported sound waves.
*/
typedef enum {
GST_AUDIO_TEST_SRC_WAVE_SINE,
GST_AUDIO_TEST_SRC_WAVE_SQUARE,
GST_AUDIO_TEST_SRC_WAVE_SAW,
GST_AUDIO_TEST_SRC_WAVE_TRIANGLE,
GST_AUDIO_TEST_SRC_WAVE_SILENCE,
GST_AUDIO_TEST_SRC_WAVE_WHITE_NOISE,
GST_AUDIO_TEST_SRC_WAVE_PINK_NOISE,
GST_AUDIO_TEST_SRC_WAVE_SINE_TAB,
GST_AUDIO_TEST_SRC_WAVE_TICKS,
GST_AUDIO_TEST_SRC_WAVE_GAUSSIAN_WHITE_NOISE
} GstAudioTestSrcWave;
#define PINK_MAX_RANDOM_ROWS (30)
#define PINK_RANDOM_BITS (16)
#define PINK_RANDOM_SHIFT ((sizeof(long)*8)-PINK_RANDOM_BITS)
typedef struct {
glong rows[PINK_MAX_RANDOM_ROWS];
glong running_sum; /* Used to optimize summing of generators. */
gint index; /* Incremented each sample. */
gint index_mask; /* Index wrapped by ANDing with this mask. */
gdouble scalar; /* Used to scale within range of -1.0 to +1.0 */
} GstPinkNoise;
typedef enum {
GST_AUDIO_TEST_SRC_FORMAT_NONE = -1,
GST_AUDIO_TEST_SRC_FORMAT_S16 = 0,
GST_AUDIO_TEST_SRC_FORMAT_S32,
GST_AUDIO_TEST_SRC_FORMAT_F32,
GST_AUDIO_TEST_SRC_FORMAT_F64
} GstAudioTestSrcFormat;
typedef struct _GstAudioTestSrc GstAudioTestSrc;
typedef struct _GstAudioTestSrcClass GstAudioTestSrcClass;
typedef void (*ProcessFunc) (GstAudioTestSrc*, guint8 *);
/**
* GstAudioTestSrc:
*
* audiotestsrc object structure.
*/
struct _GstAudioTestSrc {
GstBaseSrc parent;
ProcessFunc process;
/* parameters */
GstAudioTestSrcWave wave;
gdouble volume;
gdouble freq;
/* audio parameters */
gint channels;
gint samplerate;
gint samples_per_buffer;
gint sample_size;
GstAudioTestSrcFormat format;
/*< private >*/
gboolean tags_pushed; /* send tags just once ? */
GstClockTimeDiff timestamp_offset; /* base offset */
GstClockTime next_time; /* next timestamp */
gint64 next_sample; /* next sample to send */
gint64 next_byte; /* next byte to send */
gint64 sample_stop;
gboolean check_seek_stop;
gboolean eos_reached;
gint generate_samples_per_buffer; /* used to generate a partial buffer */
gboolean can_activate_pull;
/* waveform specific context data */
gdouble accumulator; /* phase angle */
GstPinkNoise pink;
gdouble wave_table[1024];
};
struct _GstAudioTestSrcClass {
GstBaseSrcClass parent_class;
};
GType gst_audio_test_src_get_type (void);
G_END_DECLS
#endif /* __GST_AUDIO_TEST_SRC_H__ */