Commit 86dab97c authored by Sebastian Dröge's avatar Sebastian Dröge 🍵
Browse files

gst/filter/gstbpwsinc.*: Apply the same changes to the bandpass filter:

Original commit message from CVS:
* gst/filter/gstbpwsinc.c: (gst_bpwsinc_class_init),
(gst_bpwsinc_init), (process_32), (process_64),
(bpwsinc_build_kernel), (bpwsinc_setup), (bpwsinc_get_unit_size),
(bpwsinc_transform), (bpwsinc_set_property),
(bpwsinc_get_property):
* gst/filter/gstbpwsinc.h:
Apply the same changes to the bandpass filter:
- Support double input
- Fix processing for input with >1 channels
- Specify frequency in Hz
- Specify actual filter kernel length
- Use transform instead of transform_ip as we're working
out of place anyway
- Factor out filter kernel generation and update the filter
kernel when the properties are set
Fix bandpass filter kernel generation to actually generate
a bandpass filter by creating a highpass instead of a second
lowpass.
* gst/filter/gstlpwsinc.c: (gst_lpwsinc_class_init):
Small formatting fix.
parent 6b972537
......@@ -3,6 +3,7 @@
* GStreamer
* Copyright (C) 1999-2001 Erik Walthinsen <omega@cse.ogi.edu>
* 2006 Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>
* 2007 Sebastian Dröge <slomo@circular-chaos.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
......@@ -30,9 +31,6 @@
* is probably the bottleneck
* - Implement a band reject mode (spectral inversion)
* - Allow choosing between different windows (blackman, hanning, ...)
* - Specify filter length instead of 2*N+1
* FIXME: - Doesn't work at all with >1 channels
* - Is bandreject, not bandpass
*/
#ifdef HAVE_CONFIG_H
......@@ -56,7 +54,8 @@ GST_ELEMENT_DETAILS ("Band-pass Windowed sinc filter",
"Band-pass Windowed sinc filter",
"Thomas <thomas@apestaart.org>, "
"Steven W. Smith, "
"Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>");
"Dreamlab Technologies Ltd. <mathis.hofer@dreamlab.net>, "
"Sebastian Dröge <slomo@circular-chaos.org>");
/* Filter signals and args */
enum
......@@ -74,11 +73,11 @@ enum
};
#define ALLOWED_CAPS \
"audio/x-raw-float," \
" width = (int) 32, " \
" endianness = (int) BYTE_ORDER," \
" rate = (int) [ 1, MAX ]," \
" channels = (int) [ 1, MAX ]"
"audio/x-raw-float, " \
" width = (int) { 32, 64 }, " \
" endianness = (int) BYTE_ORDER, " \
" rate = (int) [ 1, MAX ], " \
" channels = (int) [ 1, MAX ] "
#define DEBUG_INIT(bla) \
GST_DEBUG_CATEGORY_INIT (gst_bpwsinc_debug, "bpwsinc", 0, "Band-pass Windowed sinc filter plugin");
......@@ -91,8 +90,10 @@ static void bpwsinc_set_property (GObject * object, guint prop_id,
static void bpwsinc_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static GstFlowReturn bpwsinc_transform_ip (GstBaseTransform * base,
GstBuffer * outbuf);
static GstFlowReturn bpwsinc_transform (GstBaseTransform * base,
GstBuffer * inbuf, GstBuffer * outbuf);
static gboolean bpwsinc_get_unit_size (GstBaseTransform * base, GstCaps * caps,
guint * size);
static gboolean bpwsinc_setup (GstAudioFilter * base,
GstRingBufferSpec * format);
......@@ -145,133 +146,248 @@ gst_bpwsinc_class_init (GstBPWSincClass * klass)
g_object_class_install_property (gobject_class, PROP_LOWER_FREQUENCY,
g_param_spec_double ("lower-frequency", "Lower Frequency",
"Cut-off lower frequency (relative to sample rate)",
0.0, 0.5, 0, G_PARAM_READWRITE));
"Cut-off lower frequency (Hz)",
0.0, G_MAXDOUBLE, 0, G_PARAM_READWRITE));
g_object_class_install_property (gobject_class, PROP_UPPER_FREQUENCY,
g_param_spec_double ("upper-frequency", "Upper Frequency",
"Cut-off upper frequency (relative to sample rate)",
0.0, 0.5, 0, G_PARAM_READWRITE));
"Cut-off upper frequency (Hz)",
0.0, G_MAXDOUBLE, 0, G_PARAM_READWRITE));
g_object_class_install_property (gobject_class, PROP_LENGTH,
g_param_spec_int ("length", "Length",
"N such that the filter length = 2N + 1",
1, G_MAXINT, 1, G_PARAM_READWRITE));
"Filter kernel length, will be rounded to the next odd number",
3, G_MAXINT, 101, G_PARAM_READWRITE));
trans_class->transform_ip = GST_DEBUG_FUNCPTR (bpwsinc_transform_ip);
trans_class->transform = GST_DEBUG_FUNCPTR (bpwsinc_transform);
trans_class->get_unit_size = GST_DEBUG_FUNCPTR (bpwsinc_get_unit_size);
GST_AUDIO_FILTER_CLASS (klass)->setup = GST_DEBUG_FUNCPTR (bpwsinc_setup);
}
static void
gst_bpwsinc_init (GstBPWSinc * self, GstBPWSincClass * g_class)
{
self->wing_size = 50;
self->lower_frequency = 0.25;
self->upper_frequency = 0.3;
self->kernel_length = 101;
self->lower_frequency = 0.0;
self->upper_frequency = 0.0;
self->kernel = NULL;
self->have_kernel = FALSE;
self->residue = NULL;
}
static void
process_32 (GstBPWSinc * self, gfloat * src, gfloat * dst, guint input_samples)
{
gint kernel_length = self->kernel_length;
gint i, j, k, l;
gint channels = GST_AUDIO_FILTER (self)->format.channels;
/* GstAudioFilter vmethod implementations */
/* convolution */
for (i = 0; i < input_samples; i++) {
dst[i] = 0.0;
k = i % channels;
l = i / channels;
for (j = 0; j < kernel_length; j++)
if (l < j)
dst[i] +=
self->residue[(kernel_length + l - j) * channels +
k] * self->kernel[j];
else
dst[i] += src[(l - j) * channels + k] * self->kernel[j];
}
/* get notified of caps and plug in the correct process function */
static gboolean
bpwsinc_setup (GstAudioFilter * base, GstRingBufferSpec * format)
/* copy the tail of the current input buffer to the residue */
for (i = 0; i < kernel_length * channels; i++)
self->residue[i] = src[input_samples - kernel_length * channels + i];
}
static void
process_64 (GstBPWSinc * self, gdouble * src, gdouble * dst,
guint input_samples)
{
int i = 0;
double sum = 0.0;
int len = 0;
double *kernel_lp, *kernel_hp;
GstBPWSinc *self = GST_BPWSINC (base);
gint kernel_length = self->kernel_length;
gint i, j, k, l;
gint channels = GST_AUDIO_FILTER (self)->format.channels;
len = self->wing_size;
/* fill the lp kernel
* FIXME: refactor to own function, this is not caps related
*/
/* convolution */
for (i = 0; i < input_samples; i++) {
dst[i] = 0.0;
k = i % channels;
l = i / channels;
for (j = 0; j < kernel_length; j++)
if (l < j)
dst[i] +=
self->residue[(kernel_length + l - j) * channels +
k] * self->kernel[j];
else
dst[i] += src[(l - j) * channels + k] * self->kernel[j];
}
/* copy the tail of the current input buffer to the residue */
for (i = 0; i < kernel_length * channels; i++)
self->residue[i] = src[input_samples - kernel_length * channels + i];
}
static void
bpwsinc_build_kernel (GstBPWSinc * self)
{
gint i = 0;
gdouble sum = 0.0;
gint len = 0;
gdouble *kernel_lp, *kernel_hp;
gdouble w;
len = self->kernel_length;
if (GST_AUDIO_FILTER (self)->format.rate == 0) {
GST_DEBUG ("rate not set yet");
return;
}
if (GST_AUDIO_FILTER (self)->format.channels == 0) {
GST_DEBUG ("channels not set yet");
return;
}
/* Clamp frequencies */
self->lower_frequency =
CLAMP (self->lower_frequency, 0.0,
GST_AUDIO_FILTER (self)->format.rate / 2);
self->upper_frequency =
CLAMP (self->upper_frequency, 0.0,
GST_AUDIO_FILTER (self)->format.rate / 2);
if (self->lower_frequency > self->upper_frequency) {
gint tmp = self->lower_frequency;
self->lower_frequency = self->upper_frequency;
self->upper_frequency = tmp;
}
/* fill the lp kernel */
GST_DEBUG ("bpwsinc: initializing LP kernel of length %d with cut-off %f",
len * 2 + 1, self->lower_frequency);
kernel_lp = (double *) g_malloc (sizeof (double) * (2 * len + 1));
for (i = 0; i <= len * 2; ++i) {
if (i == len)
kernel_lp[i] = 2 * M_PI * self->lower_frequency;
len, self->lower_frequency);
w = 2 * M_PI * (self->lower_frequency / GST_AUDIO_FILTER (self)->format.rate);
kernel_lp = g_new (gdouble, len);
for (i = 0; i < len; ++i) {
if (i == len / 2)
kernel_lp[i] = w;
else
kernel_lp[i] = sin (2 * M_PI * self->lower_frequency * (i - len))
/ (i - len);
kernel_lp[i] = sin (w * (i - len / 2))
/ (i - len / 2);
/* Blackman windowing */
kernel_lp[i] *= (0.42 - 0.5 * cos (M_PI * i / len)
+ 0.08 * cos (2 * M_PI * i / len));
kernel_lp[i] *= (0.42 - 0.5 * cos (2 * M_PI * i / len)
+ 0.08 * cos (4 * M_PI * i / len));
}
/* normalize for unity gain at DC */
sum = 0.0;
for (i = 0; i <= len * 2; ++i)
for (i = 0; i < len; ++i)
sum += kernel_lp[i];
for (i = 0; i <= len * 2; ++i)
for (i = 0; i < len; ++i)
kernel_lp[i] /= sum;
/* fill the hp kernel */
GST_DEBUG ("bpwsinc: initializing HP kernel of length %d with cut-off %f",
len * 2 + 1, self->upper_frequency);
kernel_hp = (double *) g_malloc (sizeof (double) * (2 * len + 1));
for (i = 0; i <= len * 2; ++i) {
if (i == len)
kernel_hp[i] = 2 * M_PI * self->upper_frequency;
len, self->upper_frequency);
w = 2 * M_PI * (self->upper_frequency / GST_AUDIO_FILTER (self)->format.rate);
kernel_hp = g_new (gdouble, len);
for (i = 0; i < len; ++i) {
if (i == len / 2)
kernel_hp[i] = w;
else
kernel_hp[i] = sin (2 * M_PI * self->upper_frequency * (i - len))
/ (i - len);
kernel_hp[i] = sin (w * (i - len / 2))
/ (i - len / 2);
/* Blackman windowing */
kernel_hp[i] *= (0.42 - 0.5 * cos (M_PI * i / len)
+ 0.08 * cos (2 * M_PI * i / len));
kernel_hp[i] *= (0.42 - 0.5 * cos (2 * M_PI * i / len)
+ 0.08 * cos (4 * M_PI * i / len));
}
/* normalize for unity gain at DC */
sum = 0.0;
for (i = 0; i <= len * 2; ++i)
for (i = 0; i < len; ++i)
sum += kernel_hp[i];
for (i = 0; i <= len * 2; ++i)
for (i = 0; i < len; ++i)
kernel_hp[i] /= sum;
/* do spectral inversion to go from lowpass to highpass */
for (i = 0; i < len; ++i)
kernel_hp[i] = -kernel_hp[i];
kernel_hp[len / 2] += 1;
/* combine the two kernels */
if (self->kernel)
g_free (self->kernel);
self->kernel = (double *) g_malloc (sizeof (double) * (2 * len + 1));
self->kernel = g_new (gdouble, len);
for (i = 0; i <= len * 2; ++i)
for (i = 0; i < len; ++i)
self->kernel[i] = kernel_lp[i] + kernel_hp[i];
/* do spectral inversion to go from band reject to bandpass */
for (i = 0; i <= len * 2; ++i)
self->kernel[i] = -self->kernel[i];
self->kernel[len] += 1;
/* free the helper kernels */
g_free (kernel_lp);
g_free (kernel_hp);
/* do spectral inversion to go from bandreject to bandpass */
for (i = 0; i < len; ++i)
self->kernel[i] = -self->kernel[i];
self->kernel[len / 2] += 1;
/* set up the residue memory space */
if (self->residue)
g_free (self->residue);
self->residue = (gfloat *) g_malloc (sizeof (gfloat) * (len * 2 + 1));
for (i = 0; i <= len * 2; ++i)
self->residue[i] = 0.0;
self->residue = g_new0 (gdouble, len);
}
/* GstAudioFilter vmethod implementations */
/* get notified of caps and plug in the correct process function */
static gboolean
bpwsinc_setup (GstAudioFilter * base, GstRingBufferSpec * format)
{
GstBPWSinc *self = GST_BPWSINC (base);
gboolean ret = TRUE;
if (format->width == 32)
self->process = (GstBPWSincProcessFunc) process_32;
else if (format->width == 64)
self->process = (GstBPWSincProcessFunc) process_64;
else
ret = FALSE;
self->have_kernel = FALSE;
return TRUE;
}
/* GstBaseTransform vmethod implementations */
static gboolean
bpwsinc_get_unit_size (GstBaseTransform * base, GstCaps * caps, guint * size)
{
gint width, channels;
GstStructure *structure;
gboolean ret;
g_assert (size);
structure = gst_caps_get_structure (caps, 0);
ret = gst_structure_get_int (structure, "width", &width);
ret &= gst_structure_get_int (structure, "channels", &channels);
*size = width * channels / 8;
return ret;
}
static GstFlowReturn
bpwsinc_transform_ip (GstBaseTransform * base, GstBuffer * outbuf)
bpwsinc_transform (GstBaseTransform * base, GstBuffer * inbuf,
GstBuffer * outbuf)
{
GstBPWSinc *self = GST_BPWSINC (base);
GstClockTime timestamp;
gfloat *src;
gfloat *input;
int residue_samples;
gint input_samples;
gint total_samples;
int i, j;
gint input_samples =
GST_BUFFER_SIZE (outbuf) / (GST_AUDIO_FILTER (self)->format.width / 8);
/* don't process data in passthrough-mode */
if (gst_base_transform_is_passthrough (base))
......@@ -283,38 +399,11 @@ bpwsinc_transform_ip (GstBaseTransform * base, GstBuffer * outbuf)
if (GST_CLOCK_TIME_IS_VALID (timestamp))
gst_object_sync_values (G_OBJECT (self), timestamp);
/* FIXME: out of laziness, we copy the left-over bit from last buffer
* together with the incoming buffer to a new buffer to make the loop
* easy; self could be a lot more optimized though
* to make amends we keep the incoming buffer around and write our
* output samples there */
src = (gfloat *) GST_BUFFER_DATA (outbuf);
residue_samples = self->wing_size * 2 + 1;
input_samples = GST_BUFFER_SIZE (outbuf) / sizeof (gfloat);
total_samples = residue_samples + input_samples;
if (!self->have_kernel)
bpwsinc_build_kernel (self);
input = (gfloat *) g_malloc (sizeof (gfloat) * total_samples);
/* copy the left-over bit */
memcpy (input, self->residue, sizeof (gfloat) * residue_samples);
/* copy the new buffer */
memcpy (&input[residue_samples], src, sizeof (gfloat) * input_samples);
/* copy the tail of the current input buffer to the residue */
memcpy (self->residue, &src[input_samples - residue_samples],
sizeof (gfloat) * residue_samples);
/* convolution */
/* since we copied the previous set of samples we needed before the actual
* input data, we need to add the filter length to our indices for input */
for (i = 0; i < input_samples; ++i) {
src[i] = 0.0;
for (j = 0; j < residue_samples; ++j)
src[i] += input[i - j + residue_samples] * self->kernel[j];
}
g_free (input);
self->process (self, GST_BUFFER_DATA (inbuf), GST_BUFFER_DATA (outbuf),
input_samples);
return GST_FLOW_OK;
}
......@@ -328,14 +417,29 @@ bpwsinc_set_property (GObject * object, guint prop_id, const GValue * value,
g_return_if_fail (GST_IS_BPWSINC (self));
switch (prop_id) {
case PROP_LENGTH:
self->wing_size = g_value_get_int (value);
case PROP_LENGTH:{
gint val;
GST_BASE_TRANSFORM_LOCK (self);
val = g_value_get_int (value);
if (val % 2 == 0)
val++;
self->kernel_length = val;
bpwsinc_build_kernel (self);
GST_BASE_TRANSFORM_UNLOCK (self);
break;
}
case PROP_LOWER_FREQUENCY:
GST_BASE_TRANSFORM_LOCK (self);
self->lower_frequency = g_value_get_double (value);
bpwsinc_build_kernel (self);
GST_BASE_TRANSFORM_UNLOCK (self);
break;
case PROP_UPPER_FREQUENCY:
GST_BASE_TRANSFORM_LOCK (self);
self->upper_frequency = g_value_get_double (value);
bpwsinc_build_kernel (self);
GST_BASE_TRANSFORM_UNLOCK (self);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
......@@ -351,7 +455,7 @@ bpwsinc_get_property (GObject * object, guint prop_id, GValue * value,
switch (prop_id) {
case PROP_LENGTH:
g_value_set_int (value, self->wing_size);
g_value_set_int (value, self->kernel_length);
break;
case PROP_LOWER_FREQUENCY:
g_value_set_double (value, self->lower_frequency);
......
......@@ -25,10 +25,6 @@
* chapter 16
* available at http://www.dspguide.com/
*
* FIXME:
* - this filter is totally unoptimized !
* - we do not destroy the allocated memory for filters and residue
* - this might be improved upon with bytestream
*/
#ifndef __GST_BPWSINC_H__
......@@ -54,6 +50,8 @@ G_BEGIN_DECLS
typedef struct _GstBPWSinc GstBPWSinc;
typedef struct _GstBPWSincClass GstBPWSincClass;
typedef void (*GstBPWSincProcessFunc) (GstBPWSinc *, guint8 *, guint8 *, guint);
/**
* GstBPWSinc:
*
......@@ -62,13 +60,15 @@ typedef struct _GstBPWSincClass GstBPWSincClass;
struct _GstBPWSinc {
GstAudioFilter element;
double frequency;
double lower_frequency, upper_frequency;
int wing_size; /* length of a "wing" of the filter;
actual length is 2 * wing_size + 1 */
GstBPWSincProcessFunc process;
gdouble frequency;
gdouble lower_frequency, upper_frequency;
gint kernel_length; /* length of the filter kernel */
gfloat *residue; /* buffer for left-over samples from previous buffer */
double *kernel;
gdouble *residue; /* buffer for left-over samples from previous buffer */
gdouble *kernel;
gboolean have_kernel;
};
struct _GstBPWSincClass {
......
......@@ -126,10 +126,10 @@ gst_lpwsinc_window_get_type (void)
#define ALLOWED_CAPS \
"audio/x-raw-float," \
"audio/x-raw-float, " \
" width = (int) { 32, 64 }, " \
" endianness = (int) BYTE_ORDER," \
" rate = (int) [ 1, MAX ]," \
" endianness = (int) BYTE_ORDER, " \
" rate = (int) [ 1, MAX ], " \
" channels = (int) [ 1, MAX ]"
#define DEBUG_INIT(bla) \
......@@ -199,7 +199,7 @@ gst_lpwsinc_class_init (GstLPWSincClass * klass)
g_object_class_install_property (gobject_class, PROP_FREQUENCY,
g_param_spec_double ("frequency", "Frequency",
"Cut-off Frequency", 0.0, G_MAXDOUBLE, 0.0,
"Cut-off Frequency (Hz)", 0.0, G_MAXDOUBLE, 0.0,
G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE));
g_object_class_install_property (gobject_class, PROP_LENGTH,
......
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