318 lines
9.7 KiB
C
318 lines
9.7 KiB
C
/*
|
|
* Brickworks
|
|
*
|
|
* Copyright (C) 2023 Orastron Srl unipersonale
|
|
*
|
|
* Brickworks is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, version 3 of the License.
|
|
*
|
|
* Brickworks 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with Brickworks. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
* File author: Stefano D'Angelo
|
|
*/
|
|
|
|
/*!
|
|
* module_type {{{ dsp }}}
|
|
* version {{{ 0.3.0 }}}
|
|
* requires {{{
|
|
* bw_config bw_common bw_gain bw_math bw_mm2 bw_one_pole bw_svf
|
|
* }}}
|
|
* description {{{
|
|
* Second-order peak filter with unitary gain at DC and asymptotically
|
|
* as frequency increases.
|
|
*
|
|
* The quality factor of the underlying bandpass filter can be either
|
|
* directly controlled via the Q parameter or indirectly through the
|
|
* bandwidth parameter, which designates the distance in octaves between
|
|
* midpoint gain frequencies, i.e., frequencies with gain = peak gain / 2 in
|
|
* dB terms. The use_bandiwdth parameter allows you to choose which
|
|
* parameterization to use.
|
|
* }}}
|
|
* changelog {{{
|
|
* <ul>
|
|
* <li>Version <strong>0.3.0</strong>:
|
|
* <ul>
|
|
* <li>First release.</li>
|
|
* </ul>
|
|
* </li>
|
|
* </ul>
|
|
* }}}
|
|
*/
|
|
|
|
#ifndef _BW_PEAK_H
|
|
#define _BW_PEAK_H
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
#include <bw_common.h>
|
|
|
|
/*! api {{{
|
|
* #### bw_peak_coeffs
|
|
* ```>>> */
|
|
typedef struct _bw_peak_coeffs bw_peak_coeffs;
|
|
/*! <<<```
|
|
* Coefficients and related.
|
|
*
|
|
* #### bw_peak_state
|
|
* ```>>> */
|
|
typedef struct _bw_peak_state bw_peak_state;
|
|
/*! <<<```
|
|
* Internal state and related.
|
|
*
|
|
* #### bw_peak_init()
|
|
* ```>>> */
|
|
static inline void bw_peak_init(bw_peak_coeffs *BW_RESTRICT coeffs);
|
|
/*! <<<```
|
|
* Initializes input parameter values in `coeffs`.
|
|
*
|
|
* #### bw_peak_set_sample_rate()
|
|
* ```>>> */
|
|
static inline void bw_peak_set_sample_rate(bw_peak_coeffs *BW_RESTRICT coeffs, float sample_rate);
|
|
/*! <<<```
|
|
* Sets the `sample_rate` (Hz) value in `coeffs`.
|
|
*
|
|
* #### bw_peak_reset_coeffs()
|
|
* ```>>> */
|
|
static inline void bw_peak_reset_coeffs(bw_peak_coeffs *BW_RESTRICT coeffs);
|
|
/*! <<<```
|
|
* Resets coefficients in `coeffs` to assume their target values.
|
|
*
|
|
* #### bw_peak_reset_state()
|
|
* ```>>> */
|
|
static inline void bw_peak_reset_state(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state);
|
|
/*! <<<```
|
|
* Resets the given `state` to its initial values using the given `coeffs`.
|
|
*
|
|
* #### bw_peak_update_coeffs_ctrl()
|
|
* ```>>> */
|
|
static inline void bw_peak_update_coeffs_ctrl(bw_peak_coeffs *BW_RESTRICT coeffs);
|
|
/*! <<<```
|
|
* Triggers control-rate update of coefficients in `coeffs`.
|
|
*
|
|
* #### bw_peak_update_coeffs_audio()
|
|
* ```>>> */
|
|
static inline void bw_peak_update_coeffs_audio(bw_peak_coeffs *BW_RESTRICT coeffs);
|
|
/*! <<<```
|
|
* Triggers audio-rate update of coefficients in `coeffs`.
|
|
*
|
|
* #### bw_peak_process1()
|
|
* ```>>> */
|
|
static inline float bw_peak_process1(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, float x);
|
|
/*! <<<```
|
|
* Processes one input sample `x` using `coeffs`, while using and updating
|
|
* `state`. Returns the corresponding output sample.
|
|
*
|
|
* #### bw_peak_process()
|
|
* ```>>> */
|
|
static inline void bw_peak_process(bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, const float *x, float *y, int n_samples);
|
|
/*! <<<```
|
|
* Processes the first `n_samples` of the input buffer `x` and fills the
|
|
* first `n_samples` of the output buffer `y`, while using and updating both
|
|
* `coeffs` and `state` (control and audio rate).
|
|
*
|
|
* #### bw_peak_set_cutoff()
|
|
* ```>>> */
|
|
static inline void bw_peak_set_cutoff(bw_peak_coeffs *BW_RESTRICT coeffs, float value);
|
|
/*! <<<```
|
|
* Sets the cutoff frequency `value` (Hz) in `coeffs`.
|
|
*
|
|
* Default value: `1e3f`.
|
|
*
|
|
* #### bw_peak_set_Q()
|
|
* ```>>> */
|
|
static inline void bw_peak_set_Q(bw_mm2_coeffs *BW_RESTRICT coeffs, float value);
|
|
/*! <<<```
|
|
* Sets the quality factor to the given `value` in `coeffs`.
|
|
*
|
|
* `value` must be equal or bigger than `0.5f`.
|
|
*
|
|
* Default value: `0.5f`.
|
|
*
|
|
* #### bw_peak_set_gain_lin()
|
|
* ```>>> */
|
|
static inline void bw_peak_set_peak_gain_lin(bw_peak_coeffs *BW_RESTRICT coeffs, float value);
|
|
/*! <<<```
|
|
* Sets the peak gain parameter to the given `value` (linear gain) in
|
|
* `coeffs`.
|
|
*
|
|
* Default value: `0.f`.
|
|
*
|
|
* #### bw_peak_set_dc_gain_dB()
|
|
* ```>>> */
|
|
static inline void bw_peak_set_peak_gain_dB(bw_peak_coeffs *BW_RESTRICT coeffs, float value);
|
|
/*! <<<```
|
|
* Sets the peak gain parameter to the given `value` (dB) in `coeffs`.
|
|
*
|
|
* Default value: `-INFINITY`.
|
|
*
|
|
* #### bw_peak_set_bandiwdth()
|
|
* ```>>> */
|
|
static inline void bw_peak_set_bandwidth(bw_peak_coeffs *BW_RESTRICT coeffs, float value);
|
|
/*! <<<```
|
|
* Sets the bandwidth `value` (octaves) in `coeffs`.
|
|
*
|
|
* Default value: `0.5f`.
|
|
*
|
|
* #### bw_peak_set_use_slope()
|
|
* ```>>> */
|
|
static inline void bw_peak_set_use_bandwidth(bw_mm2_coeffs *BW_RESTRICT coeffs, char value);
|
|
/*! <<<```
|
|
* Sets whether the quality factor should be controlled via the bandwidth
|
|
* parameter (`value` non-`0`) or via the Q parameter (`0`).
|
|
*
|
|
* Default value: non-`0` (use bandwidth parameter).
|
|
* }}} */
|
|
|
|
/*** Implementation ***/
|
|
|
|
/* WARNING: This part of the file is not part of the public API. Its content may
|
|
* change at any time in future versions. Please, do not use it directly. */
|
|
|
|
#include <bw_mm2.h>
|
|
#include <bw_math.h>
|
|
|
|
struct _bw_peak_coeffs {
|
|
// Sub-components
|
|
bw_mm2_coeffs mm2_coeffs;
|
|
|
|
// Coefficients
|
|
float sg;
|
|
float isg;
|
|
|
|
// Parameters
|
|
float peak_gain;
|
|
float Q;
|
|
float bandwidth;
|
|
char use_bandwidth;
|
|
int param_changed;
|
|
};
|
|
|
|
struct _bw_peak_state {
|
|
bw_mm2_state mm2_state;
|
|
};
|
|
|
|
#define _BW_PEAK_PARAM_PEAK_GAIN 1
|
|
#define _BW_PEAK_PARAM_Q (1<<1)
|
|
#define _BW_PEAK_PARAM_BANDWIDTH (1<<2)
|
|
|
|
static inline void bw_peak_init(bw_peak_coeffs *BW_RESTRICT coeffs) {
|
|
bw_mm2_init(&coeffs->mm2_coeffs);
|
|
coeffs->peak_gain = 1.f;
|
|
coeffs->Q = 0.5f;
|
|
coeffs->bandwidth = ?; //Q=sqrt(gain)*k/(k^2-1), k=ratio f_half/f_peak
|
|
coeffs->use_bandwidth = 1;
|
|
}
|
|
|
|
static inline void bw_peak_set_sample_rate(bw_peak_coeffs *BW_RESTRICT coeffs, float sample_rate) {
|
|
bw_mm2_set_sample_rate(&coeffs->mm2_coeffs, sample_rate);
|
|
}
|
|
|
|
static inline void _bw_ls2_update_mm2_params(bw_ls1_coeffs *BW_RESTRICT coeffs) {
|
|
if (coeffs->param_changed) {
|
|
if (coeffs->param_changed & _BW_HS2_PARAM_GAIN) {
|
|
coeffs->sg = bw_math_sqrtf_2(coeffs->gain);
|
|
coeffs->isg = bw_rcpf_2(coeffs->sg);
|
|
bw_mm2_set_coeff_x(&coeffs->mm2_coeffs, coeffs->sg);
|
|
bw_mm2_set_coeff_lp(&coeffs->mm2_coeffs, 1.f - coeffs->sg);
|
|
bw_mm2_set_coeff_hp(&coeffs->mm2_coeffs, coeffs->gain - coeffs->sg);
|
|
}
|
|
if (coeffs->use_slope) {
|
|
if (coeffs->param_changed & _BW_HS2_PARAM_SLOPE) {
|
|
const float k = coeffs->sg + coeffs->isg;
|
|
bw_mm2_set_Q(&coeffs->mm2_coeffs, bw_sqrtf_2(coeffs->slope * bw_rcpf_2(coeffs->slope + coeffs->slope + k - k * coeffs->slope)));
|
|
}
|
|
}
|
|
else {
|
|
if (coeffs->param_changed & _BW_HS2_PARAM_Q)
|
|
bw_mm2_set_Q(&coeffs->mm2_coeffs, coeffs->Q);
|
|
}
|
|
coeffs->param_changed = 0;
|
|
}
|
|
}
|
|
|
|
static inline void bw_peak_reset_coeffs(bw_peak_coeffs *BW_RESTRICT coeffs) {
|
|
coeffs->param_changed = ~0;
|
|
_bw_peak_update_mm2_params(coeffs);
|
|
bw_mm2_reset_coeffs(&coeffs->mm2_coeffs);
|
|
}
|
|
|
|
static inline void bw_peak_reset_state(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state) {
|
|
bw_mm2_reset_state(&coeffs->mm2_coeffs, &state->mm2_state);
|
|
}
|
|
|
|
static inline void bw_peak_update_coeffs_ctrl(bw_peak_coeffs *BW_RESTRICT coeffs) {
|
|
_bw_peak_update_mm2_params(coeffs);
|
|
bw_mm2_update_coeffs_ctrl(&coeffs->mm2_coeffs);
|
|
}
|
|
|
|
static inline void bw_peak_update_coeffs_audio(bw_peak_coeffs *BW_RESTRICT coeffs) {
|
|
bw_mm2_update_coeffs_audio(&coeffs->mm2_coeffs);
|
|
}
|
|
|
|
static inline float bw_peak_process1(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, float x) {
|
|
return bw_mm2_process1(&coeffs->mm2_coeffs, &state->mm2_state, x);
|
|
}
|
|
|
|
static inline void bw_peak_process(bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, const float *x, float *y, int n_samples) {
|
|
bw_peak_update_coeffs_ctrl(coeffs);
|
|
for (int i = 0; i < n_samples; i++) {
|
|
bw_peak_update_coeffs_audio(coeffs);
|
|
y[i] = bw_peak_process1(coeffs, state, x[i]);
|
|
}
|
|
}
|
|
|
|
static inline void bw_peak_set_cutoff(bw_peak_coeffs *BW_RESTRICT coeffs, float value) {
|
|
bw_mm2_set_cutoff(&coeffs->mm2_coeffs, value);
|
|
}
|
|
|
|
static inline void bw_peak_set_Q(bw_mm2_coeffs *BW_RESTRICT coeffs, float value) {
|
|
if (coeffs->Q != value) {
|
|
coeffs->Q = value;
|
|
coeffs->param_changed |= _BW_HS2_PARAM_Q;
|
|
}
|
|
}
|
|
|
|
static inline void bw_peak_set_dc_gain_lin(bw_peak_coeffs *BW_RESTRICT coeffs, float value) {
|
|
if (coeffs->gain != value) {
|
|
coeffs->gain = value;
|
|
coeffs->param_changed |= _BW_HS2_PARAM_GAIN;
|
|
}
|
|
}
|
|
|
|
static inline void bw_peak_set_dc_gain_dB(bw_peak_coeffs *BW_RESTRICT coeffs, float value) {
|
|
bw_peak_set_dc_gain_lin(coeffs, bw_dB2linf_3(value));
|
|
}
|
|
|
|
static inline void bw_peak_set_slope(bw_peak_coeffs *BW_RESTRICT coeffs, float value) {
|
|
if (coeffs->slope != value) {
|
|
coeffs->slope = value;
|
|
coeffs->param_changed |= _BW_HS2_PARAM_SLOPE;
|
|
}
|
|
}
|
|
|
|
static inline void bw_peak_set_use_slope(bw_mm2_coeffs *BW_RESTRICT coeffs, char value) {
|
|
if ((coeffs->use_slope && !value) || (!coeffs->use_slope && value)) {
|
|
coeffs->use_slope = value;
|
|
coeffs->param_changed |= _BW_HS2_PARAM_Q | _BW_HS2_PARAM_SLOPE;
|
|
}
|
|
}
|
|
|
|
#undef _BW_PEAK_PARAM_GAIN
|
|
#undef _BW_PEAK_PARAM_Q
|
|
#undef _BW_PEAK_PARAM_BANDWIDTH
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif
|