static void
gst_audio_fir_filter_update_kernel (GstAudioFIRFilter * self, GValueArray * va)
{
gdouble *kernel;
guint i;
if (va) {
if (self->kernel)
g_value_array_free (self->kernel);
self->kernel = va;
}
kernel = g_new (gdouble, self->kernel->n_values);
for (i = 0; i < self->kernel->n_values; i++) {
GValue *v = g_value_array_get_nth (self->kernel, i);
kernel[i] = g_value_get_double (v);
}
gst_audio_fx_base_fir_filter_set_kernel (GST_AUDIO_FX_BASE_FIR_FILTER (self),
kernel, self->kernel->n_values, self->latency);
}
static void
gst_audio_wsinclimit_build_kernel (GstAudioWSincLimit * self,
const GstAudioInfo * info)
{
gint i = 0;
gdouble sum = 0.0;
gint len = 0;
gdouble w;
gdouble *kernel = NULL;
gint rate, channels;
len = self->kernel_length;
if (info) {
rate = GST_AUDIO_INFO_RATE (info);
channels = GST_AUDIO_INFO_CHANNELS (info);
} else {
rate = GST_AUDIO_FILTER_RATE (self);
channels = GST_AUDIO_FILTER_CHANNELS (self);
}
if (rate == 0) {
GST_DEBUG ("rate not set yet");
return;
}
if (channels == 0) {
GST_DEBUG ("channels not set yet");
return;
}
/* Clamp cutoff frequency between 0 and the nyquist frequency */
self->cutoff = CLAMP (self->cutoff, 0.0, rate / 2);
GST_DEBUG ("gst_audio_wsinclimit_: initializing filter kernel of length %d "
"with cutoff %.2lf Hz "
"for mode %s",
len, self->cutoff,
(self->mode == MODE_LOW_PASS) ? "low-pass" : "high-pass");
/* fill the kernel */
w = 2 * G_PI * (self->cutoff / rate);
kernel = g_new (gdouble, len);
for (i = 0; i < len; ++i) {
if (i == (len - 1) / 2.0)
kernel[i] = w;
else
kernel[i] = sin (w * (i - (len - 1) / 2)) / (i - (len - 1) / 2.0);
/* windowing */
switch (self->window) {
case WINDOW_HAMMING:
kernel[i] *= (0.54 - 0.46 * cos (2 * G_PI * i / (len - 1)));
break;
case WINDOW_BLACKMAN:
kernel[i] *= (0.42 - 0.5 * cos (2 * G_PI * i / (len - 1)) +
0.08 * cos (4 * G_PI * i / (len - 1)));
break;
case WINDOW_GAUSSIAN:
kernel[i] *= exp (-0.5 * POW2 (3.0 / len * (2 * i - (len - 1))));
break;
case WINDOW_COSINE:
kernel[i] *= cos (G_PI * i / (len - 1) - G_PI / 2);
break;
case WINDOW_HANN:
kernel[i] *= 0.5 * (1 - cos (2 * G_PI * i / (len - 1)));
break;
}
}
/* normalize for unity gain at DC */
for (i = 0; i < len; ++i)
sum += kernel[i];
for (i = 0; i < len; ++i)
kernel[i] /= sum;
/* convert to highpass if specified */
if (self->mode == MODE_HIGH_PASS) {
for (i = 0; i < len; ++i)
kernel[i] = -kernel[i];
if (len % 2 == 1) {
kernel[(len - 1) / 2] += 1.0;
} else {
kernel[len / 2 - 1] += 0.5;
kernel[len / 2] += 0.5;
}
}
gst_audio_fx_base_fir_filter_set_kernel (GST_AUDIO_FX_BASE_FIR_FILTER (self),
kernel, self->kernel_length, (len - 1) / 2, info);
}
static void
gst_audio_wsincband_build_kernel (GstAudioWSincBand * self)
{
gint i = 0;
gdouble sum = 0.0;
gint len = 0;
gdouble *kernel_lp, *kernel_hp;
gdouble w;
gdouble *kernel;
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;
}
GST_DEBUG ("gst_audio_wsincband: initializing filter kernel of length %d "
"with lower frequency %.2lf Hz "
", upper frequency %.2lf Hz for mode %s",
len, self->lower_frequency, self->upper_frequency,
(self->mode == MODE_BAND_PASS) ? "band-pass" : "band-reject");
/* fill the lp kernel */
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 (w * (i - len / 2))
/ (i - len / 2);
/* Windowing */
if (self->window == WINDOW_HAMMING)
kernel_lp[i] *= (0.54 - 0.46 * cos (2 * M_PI * i / len));
else
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; ++i)
sum += kernel_lp[i];
for (i = 0; i < len; ++i)
kernel_lp[i] /= sum;
/* fill the hp kernel */
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 (w * (i - len / 2))
/ (i - len / 2);
/* Windowing */
if (self->window == WINDOW_HAMMING)
kernel_hp[i] *= (0.54 - 0.46 * cos (2 * M_PI * i / len));
else
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; ++i)
sum += kernel_hp[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 */
kernel = g_new (gdouble, len);
for (i = 0; i < len; ++i)
kernel[i] = kernel_lp[i] + kernel_hp[i];
/* free the helper kernels */
g_free (kernel_lp);
g_free (kernel_hp);
/* do spectral inversion to go from bandreject to bandpass
* if specified */
if (self->mode == MODE_BAND_PASS) {
for (i = 0; i < len; ++i)
kernel[i] = -kernel[i];
kernel[len / 2] += 1;
}
gst_audio_fx_base_fir_filter_set_kernel (GST_AUDIO_FX_BASE_FIR_FILTER (self),
kernel, self->kernel_length, (len - 1) / 2);
}
static void
gst_audio_wsincband_build_kernel (GstAudioWSincBand * self,
const GstAudioInfo * info)
{
gint i = 0;
gdouble sum = 0.0;
gint len = 0;
gdouble *kernel_lp, *kernel_hp;
gdouble w;
gdouble *kernel;
gint rate, channels;
len = self->kernel_length;
if (info) {
rate = GST_AUDIO_INFO_RATE (info);
channels = GST_AUDIO_INFO_CHANNELS (info);
} else {
rate = GST_AUDIO_FILTER_RATE (self);
channels = GST_AUDIO_FILTER_CHANNELS (self);
}
if (rate == 0) {
GST_DEBUG ("rate not set yet");
return;
}
if (channels == 0) {
GST_DEBUG ("channels not set yet");
return;
}
/* Clamp frequencies */
self->lower_frequency = CLAMP (self->lower_frequency, 0.0, rate / 2);
self->upper_frequency = CLAMP (self->upper_frequency, 0.0, rate / 2);
if (self->lower_frequency > self->upper_frequency) {
gint tmp = self->lower_frequency;
self->lower_frequency = self->upper_frequency;
self->upper_frequency = tmp;
}
GST_DEBUG ("gst_audio_wsincband: initializing filter kernel of length %d "
"with lower frequency %.2lf Hz "
", upper frequency %.2lf Hz for mode %s",
len, self->lower_frequency, self->upper_frequency,
(self->mode == MODE_BAND_PASS) ? "band-pass" : "band-reject");
/* fill the lp kernel */
w = 2 * G_PI * (self->lower_frequency / rate);
kernel_lp = g_new (gdouble, len);
for (i = 0; i < len; ++i) {
if (i == (len - 1) / 2.0)
kernel_lp[i] = w;
else
kernel_lp[i] = sin (w * (i - (len - 1) / 2.0)) / (i - (len - 1) / 2.0);
/* windowing */
switch (self->window) {
case WINDOW_HAMMING:
kernel_lp[i] *= (0.54 - 0.46 * cos (2 * G_PI * i / (len - 1)));
break;
case WINDOW_BLACKMAN:
kernel_lp[i] *= (0.42 - 0.5 * cos (2 * G_PI * i / (len - 1)) +
0.08 * cos (4 * G_PI * i / (len - 1)));
break;
case WINDOW_GAUSSIAN:
kernel_lp[i] *= exp (-0.5 * POW2 (3.0 / len * (2 * i - (len - 1))));
break;
case WINDOW_COSINE:
kernel_lp[i] *= cos (G_PI * i / (len - 1) - G_PI / 2);
break;
case WINDOW_HANN:
kernel_lp[i] *= 0.5 * (1 - cos (2 * G_PI * i / (len - 1)));
break;
}
}
/* normalize for unity gain at DC */
sum = 0.0;
for (i = 0; i < len; ++i)
sum += kernel_lp[i];
for (i = 0; i < len; ++i)
kernel_lp[i] /= sum;
/* fill the hp kernel */
w = 2 * G_PI * (self->upper_frequency / rate);
kernel_hp = g_new (gdouble, len);
for (i = 0; i < len; ++i) {
if (i == (len - 1) / 2.0)
kernel_hp[i] = w;
else
kernel_hp[i] = sin (w * (i - (len - 1) / 2.0)) / (i - (len - 1) / 2.0);
/* Windowing */
switch (self->window) {
case WINDOW_HAMMING:
kernel_hp[i] *= (0.54 - 0.46 * cos (2 * G_PI * i / (len - 1)));
break;
case WINDOW_BLACKMAN:
kernel_hp[i] *= (0.42 - 0.5 * cos (2 * G_PI * i / (len - 1)) +
0.08 * cos (4 * G_PI * i / (len - 1)));
break;
case WINDOW_GAUSSIAN:
kernel_hp[i] *= exp (-0.5 * POW2 (3.0 / len * (2 * i - (len - 1))));
break;
case WINDOW_COSINE:
kernel_hp[i] *= cos (G_PI * i / (len - 1) - G_PI / 2);
break;
case WINDOW_HANN:
kernel_hp[i] *= 0.5 * (1 - cos (2 * G_PI * i / (len - 1)));
break;
}
}
/* normalize for unity gain at DC */
sum = 0.0;
for (i = 0; i < len; ++i)
sum += kernel_hp[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];
if (len % 2 == 1) {
kernel_hp[(len - 1) / 2] += 1.0;
} else {
kernel_hp[len / 2 - 1] += 0.5;
kernel_hp[len / 2] += 0.5;
}
/* combine the two kernels */
kernel = g_new (gdouble, len);
for (i = 0; i < len; ++i)
kernel[i] = kernel_lp[i] + kernel_hp[i];
/* free the helper kernels */
g_free (kernel_lp);
g_free (kernel_hp);
/* do spectral inversion to go from bandreject to bandpass
* if specified */
if (self->mode == MODE_BAND_PASS) {
for (i = 0; i < len; ++i)
kernel[i] = -kernel[i];
kernel[len / 2] += 1;
}
gst_audio_fx_base_fir_filter_set_kernel (GST_AUDIO_FX_BASE_FIR_FILTER (self),
kernel, self->kernel_length, (len - 1) / 2, info);
}
