903 lines
28 KiB
C++
903 lines
28 KiB
C++
/*
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* Brickworks
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*
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* Copyright (C) 2022-2024 Orastron Srl unipersonale
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*
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* Brickworks is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, version 3 of the License.
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*
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* Brickworks is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with Brickworks. If not, see <http://www.gnu.org/licenses/>.
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*
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* File author: Stefano D'Angelo
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*/
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/*!
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* module_type {{{ dsp }}}
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* version {{{ 1.1.0 }}}
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* requires {{{ bw_common bw_math bw_one_pole }}}
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* description {{{
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* Antialiased tanh-based saturation with parametric bias and gain
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* (compensation) and output bias removal.
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*
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* In other words this implements (approximately)
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*
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* > y(n) = tanh(gain \* x(n) + bias) - tanh(bias)
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*
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* with antialiasing and optionally dividing the output by gain.
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*
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* As a side effect, antialiasing causes attenuation at higher frequencies
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* (about 3 dB at 0.5 × Nyquist frequency and rapidly increasing at higher
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* frequencies).
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*
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* The antialiasing technique used here is described in
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*
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* J. D. Parker, V. Zavalishin, and E. Le Bivic, "Reducing the Aliasing of
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* Nonlinear Waveshaping Using Continuous-Time Convolution", Proc. 19th Intl.
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* Conf. Digital Audio Effects (DAFx-16), pp. 137-144, Brno, Czech Republic,
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* September 2016.
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* }}}
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* changelog {{{
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* <ul>
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* <li>Version <strong>1.1.0</strong>:
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* <ul>
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* <li>Now using <code>BW_NULL</code> and
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* <code>BW_CXX_NO_ARRAY</code>.</li>
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* </ul>
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* </li>
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* <li>Version <strong>1.0.0</strong>:
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* <ul>
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* <li>Changed default value for gain compensation to off.</li>
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* <li>Added initial input value to
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* <code>bw_satur_reset_state()</code>.</li>
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* <li>Added <code>bw_satur_reset_state_multi()</code> and updated C++
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* API in this regard.</li>
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* <li>Now <code>bw_satur_reset_state()</code> returns the initial
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* output value.</li>
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* <li>Added overloaded C++ <code>reset()</code> functions taking
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* arrays as arguments.</li>
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* <li><code>bw_satur_process()</code> and
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* <code>bw_satur_process_multi()</code> now use
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* <code>size_t</code> to count samples and channels.</li>
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* <li>Added more <code>const</code> and <code>BW_RESTRICT</code>
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* specifiers to input arguments and implementation.</li>
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* <li>Moved C++ code to C header.</li>
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* <li>Added overloaded C++ <code>process()</code> function taking
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* C-style arrays as arguments.</li>
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* <li>Removed usage of reserved identifiers.</li>
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* <li>Clearly specified parameter validity ranges.</li>
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* <li>Added debugging code.</li>
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* </ul>
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* </li>
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* <li>Version <strong>0.6.0</strong>:
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* <ul>
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* <li>Removed dependency on bw_config.</li>
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* </ul>
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* </li>
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* <li>Version <strong>0.5.0</strong>:
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* <ul>
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* <li>Added <code>bw_satur_process_multi()</code>.</li>
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* <li>Fixed gain coefficient reset bug.</li>
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* <li>Fixed initial state bug.</li>
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* <li>Added C++ wrapper.</li>
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* </ul>
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* </li>
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* <li>Version <strong>0.4.0</strong>:
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* <ul>
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* <li>Fixed unused parameter warnings.</li>
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* </ul>
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* </li>
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* <li>Version <strong>0.2.0</strong>:
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* <ul>
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* <li>First release.</li>
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* </ul>
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* </li>
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* </ul>
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* }}}
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*/
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#ifndef BW_SATUR_H
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#define BW_SATUR_H
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#include <bw_common.h>
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#ifdef __cplusplus
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extern "C" {
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#endif
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/*! api {{{
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* #### bw_satur_coeffs
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* ```>>> */
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typedef struct bw_satur_coeffs bw_satur_coeffs;
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/*! <<<```
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* Coefficients and related.
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*
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* #### bw_satur_state
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* ```>>> */
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typedef struct bw_satur_state bw_satur_state;
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/*! <<<```
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* Internal state and related.
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*
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* #### bw_satur_init()
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* ```>>> */
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static inline void bw_satur_init(
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bw_satur_coeffs * BW_RESTRICT coeffs);
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/*! <<<```
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* Initializes input parameter values in `coeffs`.
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*
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* #### bw_satur_set_sample_rate()
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* ```>>> */
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static inline void bw_satur_set_sample_rate(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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float sample_rate);
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/*! <<<```
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* Sets the `sample_rate` (Hz) value in `coeffs`.
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*
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* #### bw_satur_reset_coeffs()
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* ```>>> */
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static inline void bw_satur_reset_coeffs(
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bw_satur_coeffs * BW_RESTRICT coeffs);
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/*! <<<```
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* Resets coefficients in `coeffs` to assume their target values.
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*
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* #### bw_satur_reset_state()
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* ```>>> */
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static inline float bw_satur_reset_state(
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const bw_satur_coeffs * BW_RESTRICT coeffs,
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bw_satur_state * BW_RESTRICT state,
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float x_0);
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/*! <<<```
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* Resets the given `state` to its initial values using the given `coeffs`
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* and the initial input value `x_0`.
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*
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* Returns the corresponding initial output value.
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*
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* #### bw_satur_reset_state_multi()
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* ```>>> */
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static inline void bw_satur_reset_state_multi(
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const bw_satur_coeffs * BW_RESTRICT coeffs,
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bw_satur_state * BW_RESTRICT const * BW_RESTRICT state,
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const float * x_0,
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float * y_0,
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size_t n_channels);
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/*! <<<```
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* Resets each of the `n_channels` `state`s to its initial values using the
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* given `coeffs` and the corresponding initial input value in the `x_0`
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* array.
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*
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* The corresponding initial output values are written into the `y_0` array,
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* if not `BW_NULL`.
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*
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* #### bw_satur_update_coeffs_ctrl()
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* ```>>> */
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static inline void bw_satur_update_coeffs_ctrl(
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bw_satur_coeffs * BW_RESTRICT coeffs);
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/*! <<<```
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* Triggers control-rate update of coefficients in `coeffs`.
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*
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* #### bw_satur_update_coeffs_audio()
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* ```>>> */
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static inline void bw_satur_update_coeffs_audio(
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bw_satur_coeffs * BW_RESTRICT coeffs);
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/*! <<<```
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* Triggers audio-rate update of coefficients in `coeffs`.
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*
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* #### bw_satur_process1()
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* ```>>> */
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static inline float bw_satur_process1(
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const bw_satur_coeffs * BW_RESTRICT coeffs,
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bw_satur_state * BW_RESTRICT state,
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float x);
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static inline float bw_satur_process1_comp(
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const bw_satur_coeffs * BW_RESTRICT coeffs,
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bw_satur_state * BW_RESTRICT state,
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float x);
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/*! <<<```
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* These function process one input sample `x` using `coeffs`, while using
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* and updating `state`. They return the corresponding output sample.
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*
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* In particular:
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* * `bw_satur_process1()` assumes that gain compensation is disabled;
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* * `bw_satur_process1_comp()` assumes that gain compensation is enabled.
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*
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* The actual gain compensation parameter value is ignored.
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*
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* #### bw_satur_process()
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* ```>>> */
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static inline void bw_satur_process(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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bw_satur_state * BW_RESTRICT state,
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const float * x,
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float * y,
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size_t n_samples);
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/*! <<<```
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* Processes the first `n_samples` of the input buffer `x` and fills the
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* first `n_samples` of the output buffer `y`, while using and updating both
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* `coeffs` and `state` (control and audio rate).
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*
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* #### bw_satur_process_multi()
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* ```>>> */
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static inline void bw_satur_process_multi(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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bw_satur_state * BW_RESTRICT const * BW_RESTRICT state,
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const float * const * x,
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float * const * y,
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size_t n_channels,
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size_t n_samples);
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/*! <<<```
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* Processes the first `n_samples` of the `n_channels` input buffers `x` and
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* fills the first `n_samples` of the `n_channels` output buffers `y`, while
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* using and updating both the common `coeffs` and each of the `n_channels`
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* `state`s (control and audio rate).
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*
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* #### bw_satur_set_bias()
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* ```>>> */
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static inline void bw_satur_set_bias(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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float value);
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/*! <<<```
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* Sets the input bias `value` in `coeffs`.
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*
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* Valid range: [`-1e12f`, `1e12f`].
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*
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* Default value: `0.f`.
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*
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* #### bw_satur_set_gain()
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* ```>>> */
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static inline void bw_satur_set_gain(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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float value);
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/*! <<<```
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* Sets the gain `value` in `coeffs`.
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*
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* Valid range: [`1e-12f`, `1e12f`].
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*
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* Default value: `1.f`.
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*
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* #### bw_satur_set_gain_compensation()
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* ```>>> */
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static inline void bw_satur_set_gain_compensation(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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char value);
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/*! <<<```
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* Sets whether the output should be divided by gain (`value` non-`0`) or not
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* (`0`).
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*
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* Default value: `0` (off).
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*
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* #### bw_satur_coeffs_is_valid()
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* ```>>> */
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static inline char bw_satur_coeffs_is_valid(
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const bw_satur_coeffs * BW_RESTRICT coeffs);
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/*! <<<```
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* Tries to determine whether `coeffs` is valid and returns non-`0` if it
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* seems to be the case and `0` if it is certainly not. False positives are
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* possible, false negatives are not.
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*
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* `coeffs` must at least point to a readable memory block of size greater
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* than or equal to that of `bw_satur_coeffs`.
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*
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* #### bw_satur_state_is_valid()
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* ```>>> */
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static inline char bw_satur_state_is_valid(
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const bw_satur_coeffs * BW_RESTRICT coeffs,
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const bw_satur_state * BW_RESTRICT state);
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/*! <<<```
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* Tries to determine whether `state` is valid and returns non-`0` if it
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* seems to be the case and `0` if it is certainly not. False positives are
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* possible, false negatives are not.
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*
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* If `coeffs` is not `BW_NULL` extra cross-checks might be performed
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* (`state` is supposed to be associated to `coeffs`).
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*
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* `state` must at least point to a readable memory block of size greater
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* than or equal to that of `bw_satur_state`.
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* }}} */
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#ifdef __cplusplus
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}
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#endif
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/*** Implementation ***/
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/* WARNING: This part of the file is not part of the public API. Its content may
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* change at any time in future versions. Please, do not use it directly. */
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#include <bw_math.h>
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#include <bw_one_pole.h>
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#ifdef __cplusplus
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extern "C" {
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#endif
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#ifdef BW_DEBUG_DEEP
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enum bw_satur_coeffs_state {
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bw_satur_coeffs_state_invalid,
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bw_satur_coeffs_state_init,
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bw_satur_coeffs_state_set_sample_rate,
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bw_satur_coeffs_state_reset_coeffs
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};
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#endif
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struct bw_satur_coeffs {
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#ifdef BW_DEBUG_DEEP
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uint32_t hash;
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enum bw_satur_coeffs_state state;
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uint32_t reset_id;
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#endif
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// Sub-components
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bw_one_pole_coeffs smooth_coeffs;
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bw_one_pole_state smooth_bias_state;
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bw_one_pole_state smooth_gain_state;
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// Coefficients
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float bias_dc;
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float inv_gain;
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// Parameters
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float bias;
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float gain;
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char gain_compensation;
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};
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struct bw_satur_state {
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#ifdef BW_DEBUG_DEEP
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uint32_t hash;
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uint32_t coeffs_reset_id;
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#endif
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// States
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float x_z1;
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float F_z1;
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};
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static inline float bw_satur_tanhf(
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float x) {
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const float xm = bw_clipf(x, -2.115287308554551f, 2.115287308554551f);
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const float axm = bw_absf(xm);
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return xm * axm * (0.01218073260037716f * axm - 0.2750231331124371f) + xm;
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}
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static inline void bw_satur_init(
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bw_satur_coeffs * BW_RESTRICT coeffs) {
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BW_ASSERT(coeffs != BW_NULL);
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bw_one_pole_init(&coeffs->smooth_coeffs);
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bw_one_pole_set_tau(&coeffs->smooth_coeffs, 0.005f);
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bw_one_pole_set_sticky_thresh(&coeffs->smooth_coeffs, 1e-3f);
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coeffs->bias = 0.f;
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coeffs->gain = 1.f;
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coeffs->gain_compensation = 0;
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#ifdef BW_DEBUG_DEEP
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coeffs->hash = bw_hash_sdbm("bw_satur_coeffs");
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coeffs->state = bw_satur_coeffs_state_init;
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coeffs->reset_id = coeffs->hash + 1;
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#endif
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BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state == bw_satur_coeffs_state_init);
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}
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static inline void bw_satur_set_sample_rate(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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float sample_rate) {
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BW_ASSERT(coeffs != BW_NULL);
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BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_init);
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BW_ASSERT(bw_is_finite(sample_rate) && sample_rate > 0.f);
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bw_one_pole_set_sample_rate(&coeffs->smooth_coeffs, sample_rate);
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bw_one_pole_reset_coeffs(&coeffs->smooth_coeffs);
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#ifdef BW_DEBUG_DEEP
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coeffs->state = bw_satur_coeffs_state_set_sample_rate;
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#endif
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BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state == bw_satur_coeffs_state_set_sample_rate);
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}
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static inline void bw_satur_do_update_coeffs(
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bw_satur_coeffs * BW_RESTRICT coeffs,
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char force) {
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float bias_cur = bw_one_pole_get_y_z1(&coeffs->smooth_bias_state);
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if (force || coeffs->bias != bias_cur) {
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bias_cur = bw_one_pole_process1_sticky_abs(&coeffs->smooth_coeffs, &coeffs->smooth_bias_state, coeffs->bias);
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coeffs->bias_dc = bw_satur_tanhf(bias_cur);
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}
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float gain_cur = bw_one_pole_get_y_z1(&coeffs->smooth_gain_state);
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if (force || coeffs->gain != gain_cur) {
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gain_cur = bw_one_pole_process1_sticky_rel(&coeffs->smooth_coeffs, &coeffs->smooth_gain_state, coeffs->gain);
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coeffs->inv_gain = bw_rcpf(gain_cur);
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}
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}
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static inline void bw_satur_reset_coeffs(
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bw_satur_coeffs * BW_RESTRICT coeffs) {
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BW_ASSERT(coeffs != BW_NULL);
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BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_set_sample_rate);
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bw_one_pole_reset_state(&coeffs->smooth_coeffs, &coeffs->smooth_bias_state, coeffs->bias);
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bw_one_pole_reset_state(&coeffs->smooth_coeffs, &coeffs->smooth_gain_state, coeffs->gain);
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bw_satur_do_update_coeffs(coeffs, 1);
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#ifdef BW_DEBUG_DEEP
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coeffs->state = bw_satur_coeffs_state_reset_coeffs;
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coeffs->reset_id++;
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#endif
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BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state == bw_satur_coeffs_state_reset_coeffs);
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}
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static inline float bw_satur_reset_state(
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const bw_satur_coeffs * BW_RESTRICT coeffs,
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bw_satur_state * BW_RESTRICT state,
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float x_0) {
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BW_ASSERT(coeffs != BW_NULL);
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BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
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BW_ASSERT(state != BW_NULL);
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BW_ASSERT(bw_is_finite(x_0));
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|
||
const float x = bw_one_pole_get_y_z1(&coeffs->smooth_gain_state) * x_0 + bw_one_pole_get_y_z1(&coeffs->smooth_bias_state);
|
||
const float ax = bw_absf(x);
|
||
const float F = ax >= 2.115287308554551f ? ax - 0.6847736211329452f : ax * ax * ((0.00304518315009429f * ax - 0.09167437770414569f) * ax + 0.5f);
|
||
const float yb = bw_satur_tanhf(x);
|
||
const float y = (coeffs->gain_compensation ? coeffs->inv_gain : 1.f) * (yb - coeffs->bias_dc);
|
||
state->x_z1 = x;
|
||
state->F_z1 = F;
|
||
|
||
#ifdef BW_DEBUG_DEEP
|
||
state->hash = bw_hash_sdbm("bw_satur_state");
|
||
state->coeffs_reset_id = coeffs->reset_id;
|
||
#endif
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT_DEEP(bw_satur_state_is_valid(coeffs, state));
|
||
BW_ASSERT(bw_is_finite(y));
|
||
|
||
return y;
|
||
}
|
||
|
||
static inline void bw_satur_reset_state_multi(
|
||
const bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
bw_satur_state * BW_RESTRICT const * BW_RESTRICT state,
|
||
const float * x_0,
|
||
float * y_0,
|
||
size_t n_channels) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT(state != BW_NULL);
|
||
#ifndef BW_NO_DEBUG
|
||
for (size_t i = 0; i < n_channels; i++)
|
||
for (size_t j = i + 1; j < n_channels; j++)
|
||
BW_ASSERT(state[i] != state[j]);
|
||
#endif
|
||
BW_ASSERT(x_0 != BW_NULL);
|
||
|
||
if (y_0 != BW_NULL)
|
||
for (size_t i = 0; i < n_channels; i++)
|
||
y_0[i] = bw_satur_reset_state(coeffs, state[i], x_0[i]);
|
||
else
|
||
for (size_t i = 0; i < n_channels; i++)
|
||
bw_satur_reset_state(coeffs, state[i], x_0[i]);
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT_DEEP(y_0 != BW_NULL ? bw_has_only_finite(y_0, n_channels) : 1);
|
||
}
|
||
|
||
static inline void bw_satur_update_coeffs_ctrl(
|
||
bw_satur_coeffs * BW_RESTRICT coeffs) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
|
||
(void)coeffs;
|
||
}
|
||
|
||
static inline void bw_satur_update_coeffs_audio(
|
||
bw_satur_coeffs * BW_RESTRICT coeffs) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
|
||
bw_satur_do_update_coeffs(coeffs, 0);
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
}
|
||
|
||
static inline float bw_satur_process1(
|
||
const bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
bw_satur_state * BW_RESTRICT state,
|
||
float x) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT(state != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_state_is_valid(coeffs, state));
|
||
BW_ASSERT(bw_is_finite(x));
|
||
|
||
x = bw_one_pole_get_y_z1(&coeffs->smooth_gain_state) * x + bw_one_pole_get_y_z1(&coeffs->smooth_bias_state);
|
||
const float ax = bw_absf(x);
|
||
const float F = ax >= 2.115287308554551f ? ax - 0.6847736211329452f : ax * ax * ((0.00304518315009429f * ax - 0.09167437770414569f) * ax + 0.5f);
|
||
const float d = x - state->x_z1;
|
||
const float yb = d * d < 1e-6f ? bw_satur_tanhf(0.5f * (x + state->x_z1)) : (F - state->F_z1) * bw_rcpf(d);
|
||
const float y = yb - coeffs->bias_dc;
|
||
state->x_z1 = x;
|
||
state->F_z1 = F;
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT_DEEP(bw_satur_state_is_valid(coeffs, state));
|
||
BW_ASSERT(bw_is_finite(y));
|
||
|
||
return y;
|
||
}
|
||
|
||
static inline float bw_satur_process1_comp(
|
||
const bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
bw_satur_state * BW_RESTRICT state,
|
||
float x) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT(state != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_state_is_valid(coeffs, state));
|
||
BW_ASSERT(bw_is_finite(x));
|
||
|
||
const float y = coeffs->inv_gain * bw_satur_process1(coeffs, state, x);
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT_DEEP(bw_satur_state_is_valid(coeffs, state));
|
||
BW_ASSERT(bw_is_finite(y));
|
||
|
||
return y;
|
||
}
|
||
|
||
static inline void bw_satur_process(
|
||
bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
bw_satur_state * BW_RESTRICT state,
|
||
const float * x,
|
||
float * y,
|
||
size_t n_samples) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT(state != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_state_is_valid(coeffs, state));
|
||
BW_ASSERT(x != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_has_only_finite(x, n_samples));
|
||
BW_ASSERT(y != BW_NULL);
|
||
|
||
if (coeffs->gain_compensation)
|
||
for (size_t i = 0; i < n_samples; i++) {
|
||
bw_satur_update_coeffs_audio(coeffs);
|
||
y[i] = bw_satur_process1_comp(coeffs, state, x[i]);
|
||
}
|
||
else
|
||
for (size_t i = 0; i < n_samples; i++) {
|
||
bw_satur_update_coeffs_audio(coeffs);
|
||
y[i] = bw_satur_process1(coeffs, state, x[i]);
|
||
}
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT_DEEP(bw_satur_state_is_valid(coeffs, state));
|
||
BW_ASSERT_DEEP(bw_has_only_finite(y, n_samples));
|
||
}
|
||
|
||
static inline void bw_satur_process_multi(
|
||
bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
bw_satur_state * BW_RESTRICT const * BW_RESTRICT state,
|
||
const float * const * x,
|
||
float * const * y,
|
||
size_t n_channels,
|
||
size_t n_samples) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
BW_ASSERT(state != BW_NULL);
|
||
#ifndef BW_NO_DEBUG
|
||
for (size_t i = 0; i < n_channels; i++)
|
||
for (size_t j = i + 1; j < n_channels; j++)
|
||
BW_ASSERT(state[i] != state[j]);
|
||
#endif
|
||
BW_ASSERT(x != BW_NULL);
|
||
BW_ASSERT(y != BW_NULL);
|
||
#ifndef BW_NO_DEBUG
|
||
for (size_t i = 0; i < n_channels; i++)
|
||
for (size_t j = i + 1; j < n_channels; j++)
|
||
BW_ASSERT(y[i] != y[j]);
|
||
#endif
|
||
|
||
bw_satur_update_coeffs_ctrl(coeffs);
|
||
for (size_t i = 0; i < n_samples; i++) {
|
||
bw_satur_update_coeffs_audio(coeffs);
|
||
for (size_t j = 0; j < n_channels; j++)
|
||
y[j][i] = bw_satur_process1(coeffs, state[j], x[j][i]);
|
||
}
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_reset_coeffs);
|
||
}
|
||
|
||
static inline void bw_satur_set_bias(
|
||
bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
float value) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_init);
|
||
BW_ASSERT(bw_is_finite(value));
|
||
BW_ASSERT(value >= -1e12f && value <= 1e12f);
|
||
|
||
coeffs->bias = value;
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_init);
|
||
}
|
||
|
||
static inline void bw_satur_set_gain(
|
||
bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
float value) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_init);
|
||
BW_ASSERT(bw_is_finite(value));
|
||
BW_ASSERT(value >= 1e-12f && value <= 1e12f);
|
||
|
||
coeffs->gain = value;
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_init);
|
||
}
|
||
|
||
static inline void bw_satur_set_gain_compensation(
|
||
bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
char value) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_init);
|
||
|
||
coeffs->gain_compensation = value;
|
||
|
||
BW_ASSERT_DEEP(bw_satur_coeffs_is_valid(coeffs));
|
||
BW_ASSERT_DEEP(coeffs->state >= bw_satur_coeffs_state_init);
|
||
}
|
||
|
||
static inline char bw_satur_coeffs_is_valid(
|
||
const bw_satur_coeffs * BW_RESTRICT coeffs) {
|
||
BW_ASSERT(coeffs != BW_NULL);
|
||
|
||
#ifdef BW_DEBUG_DEEP
|
||
if (coeffs->hash != bw_hash_sdbm("bw_satur_coeffs"))
|
||
return 0;
|
||
if (coeffs->state < bw_satur_coeffs_state_init || coeffs->state > bw_satur_coeffs_state_reset_coeffs)
|
||
return 0;
|
||
#endif
|
||
|
||
if (!bw_is_finite(coeffs->bias) || coeffs->bias < -1e12f || coeffs->bias > 1e12f)
|
||
return 0;
|
||
if (!bw_is_finite(coeffs->gain) || coeffs->gain < 1e-12f || coeffs->gain > 1e12f)
|
||
return 0;
|
||
|
||
if (!bw_one_pole_coeffs_is_valid(&coeffs->smooth_coeffs))
|
||
return 0;
|
||
|
||
#ifdef BW_DEBUG_DEEP
|
||
if (coeffs->state >= bw_satur_coeffs_state_reset_coeffs) {
|
||
if (!bw_one_pole_state_is_valid(&coeffs->smooth_coeffs, &coeffs->smooth_bias_state))
|
||
return 0;
|
||
if (!bw_one_pole_state_is_valid(&coeffs->smooth_coeffs, &coeffs->smooth_gain_state))
|
||
return 0;
|
||
|
||
if (!bw_is_finite(coeffs->bias_dc) || coeffs->bias_dc < -1.f || coeffs->bias_dc > 1.f)
|
||
return 0;
|
||
if (!bw_is_finite(coeffs->inv_gain) || coeffs->inv_gain <= 0.f)
|
||
return 0;
|
||
}
|
||
#endif
|
||
|
||
return 1;
|
||
}
|
||
|
||
static inline char bw_satur_state_is_valid(
|
||
const bw_satur_coeffs * BW_RESTRICT coeffs,
|
||
const bw_satur_state * BW_RESTRICT state) {
|
||
BW_ASSERT(state != BW_NULL);
|
||
|
||
#ifdef BW_DEBUG_DEEP
|
||
if (state->hash != bw_hash_sdbm("bw_satur_state"))
|
||
return 0;
|
||
|
||
if (coeffs != BW_NULL && coeffs->reset_id != state->coeffs_reset_id)
|
||
return 0;
|
||
#endif
|
||
|
||
(void)coeffs;
|
||
|
||
return bw_is_finite(state->x_z1) && bw_is_finite(state->F_z1);
|
||
}
|
||
|
||
#ifdef __cplusplus
|
||
}
|
||
|
||
#ifndef BW_CXX_NO_ARRAY
|
||
# include <array>
|
||
#endif
|
||
|
||
namespace Brickworks {
|
||
|
||
/*** Public C++ API ***/
|
||
|
||
/*! api_cpp {{{
|
||
* ##### Brickworks::Satur
|
||
* ```>>> */
|
||
template<size_t N_CHANNELS>
|
||
class Satur {
|
||
public:
|
||
Satur();
|
||
|
||
void setSampleRate(
|
||
float sampleRate);
|
||
|
||
void reset(
|
||
float x0 = 0.f,
|
||
float * BW_RESTRICT y0 = nullptr);
|
||
|
||
#ifndef BW_CXX_NO_ARRAY
|
||
void reset(
|
||
float x0,
|
||
std::array<float, N_CHANNELS> * BW_RESTRICT y0);
|
||
#endif
|
||
|
||
void reset(
|
||
const float * x0,
|
||
float * y0 = nullptr);
|
||
|
||
#ifndef BW_CXX_NO_ARRAY
|
||
void reset(
|
||
std::array<float, N_CHANNELS> x0,
|
||
std::array<float, N_CHANNELS> * BW_RESTRICT y0 = nullptr);
|
||
#endif
|
||
|
||
void process(
|
||
const float * const * x,
|
||
float * const * y,
|
||
size_t nSamples);
|
||
|
||
#ifndef BW_CXX_NO_ARRAY
|
||
void process(
|
||
std::array<const float *, N_CHANNELS> x,
|
||
std::array<float *, N_CHANNELS> y,
|
||
size_t nSamples);
|
||
#endif
|
||
|
||
void setBias(
|
||
float value);
|
||
|
||
void setGain(
|
||
float value);
|
||
|
||
void setGainCompensation(
|
||
bool value);
|
||
/*! <<<...
|
||
* }
|
||
* ```
|
||
* }}} */
|
||
|
||
/*** 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. */
|
||
|
||
private:
|
||
bw_satur_coeffs coeffs;
|
||
bw_satur_state states[N_CHANNELS];
|
||
bw_satur_state * BW_RESTRICT statesP[N_CHANNELS];
|
||
};
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline Satur<N_CHANNELS>::Satur() {
|
||
bw_satur_init(&coeffs);
|
||
for (size_t i = 0; i < N_CHANNELS; i++)
|
||
statesP[i] = states + i;
|
||
}
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::setSampleRate(
|
||
float sampleRate) {
|
||
bw_satur_set_sample_rate(&coeffs, sampleRate);
|
||
}
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::reset(
|
||
float x0,
|
||
float * BW_RESTRICT y0) {
|
||
bw_satur_reset_coeffs(&coeffs);
|
||
if (y0 != nullptr)
|
||
for (size_t i = 0; i < N_CHANNELS; i++)
|
||
y0[i] = bw_satur_reset_state(&coeffs, states + i, x0);
|
||
else
|
||
for (size_t i = 0; i < N_CHANNELS; i++)
|
||
bw_satur_reset_state(&coeffs, states + i, x0);
|
||
}
|
||
|
||
#ifndef BW_CXX_NO_ARRAY
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::reset(
|
||
float x0,
|
||
std::array<float, N_CHANNELS> * BW_RESTRICT y0) {
|
||
reset(x0, y0 != nullptr ? y0->data() : nullptr);
|
||
}
|
||
#endif
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::reset(
|
||
const float * x0,
|
||
float * y0) {
|
||
bw_satur_reset_coeffs(&coeffs);
|
||
bw_satur_reset_state_multi(&coeffs, statesP, x0, y0, N_CHANNELS);
|
||
}
|
||
|
||
#ifndef BW_CXX_NO_ARRAY
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::reset(
|
||
std::array<float, N_CHANNELS> x0,
|
||
std::array<float, N_CHANNELS> * BW_RESTRICT y0) {
|
||
reset(x0.data(), y0 != nullptr ? y0->data() : nullptr);
|
||
}
|
||
#endif
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::process(
|
||
const float * const * x,
|
||
float * const * y,
|
||
size_t nSamples) {
|
||
bw_satur_process_multi(&coeffs, statesP, x, y, N_CHANNELS, nSamples);
|
||
}
|
||
|
||
#ifndef BW_CXX_NO_ARRAY
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::process(
|
||
std::array<const float *, N_CHANNELS> x,
|
||
std::array<float *, N_CHANNELS> y,
|
||
size_t nSamples) {
|
||
process(x.data(), y.data(), nSamples);
|
||
}
|
||
#endif
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::setBias(
|
||
float value) {
|
||
bw_satur_set_bias(&coeffs, value);
|
||
}
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::setGain(
|
||
float value) {
|
||
bw_satur_set_gain(&coeffs, value);
|
||
}
|
||
|
||
template<size_t N_CHANNELS>
|
||
inline void Satur<N_CHANNELS>::setGainCompensation(
|
||
bool value) {
|
||
bw_satur_set_gain_compensation(&coeffs, value);
|
||
}
|
||
|
||
}
|
||
#endif
|
||
|
||
#endif
|