858 lines
26 KiB
C++
858 lines
26 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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* First-order lowpass filter (6 dB/oct) with unitary DC gain.
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*
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* This is better suited to filtering actual audio than
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* [bw_one_pole](bw_one_pole).
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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>Limited actual prewarping frequency to prevent instability.</li>
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* <li>Added <code>bw_lp1_reset_state_multi()</code> and updated C++
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* API in this regard.</li>
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* <li>Now <code>bw_lp1_reset_state()</code> returns the initial output
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* value.</li>
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* <li><code>bw_lp1_process()</code> and
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* <code>bw_lp1_process_multi()</code> now use <code>size_t</code>
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* 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_lp1_process_multi()</code>.</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>Added initial input value to
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* <code>bw_lp1_reset_state()</code>.</li>
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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>0.3.0</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_LP1_H
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#define BW_LP1_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_lp1_coeffs
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* ```>>> */
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typedef struct bw_lp1_coeffs bw_lp1_coeffs;
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/*! <<<```
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* Coefficients and related.
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*
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* #### bw_lp1_state
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* ```>>> */
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typedef struct bw_lp1_state bw_lp1_state;
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/*! <<<```
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* Internal state and related.
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*
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* #### bw_lp1_init()
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* ```>>> */
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static inline void bw_lp1_init(
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bw_lp1_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_lp1_set_sample_rate()
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* ```>>> */
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static inline void bw_lp1_set_sample_rate(
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bw_lp1_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_lp1_reset_coeffs()
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* ```>>> */
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static inline void bw_lp1_reset_coeffs(
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bw_lp1_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_lp1_reset_state()
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* ```>>> */
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static inline float bw_lp1_reset_state(
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const bw_lp1_coeffs * BW_RESTRICT coeffs,
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bw_lp1_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_lp1_reset_state_multi()
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* ```>>> */
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static inline void bw_lp1_reset_state_multi(
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const bw_lp1_coeffs * BW_RESTRICT coeffs,
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bw_lp1_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_lp1_update_coeffs_ctrl()
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* ```>>> */
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static inline void bw_lp1_update_coeffs_ctrl(
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bw_lp1_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_lp1_update_coeffs_audio()
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* ```>>> */
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static inline void bw_lp1_update_coeffs_audio(
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bw_lp1_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_lp1_process1()
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* ```>>> */
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static inline float bw_lp1_process1(
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const bw_lp1_coeffs * BW_RESTRICT coeffs,
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bw_lp1_state * BW_RESTRICT state,
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float x);
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/*! <<<```
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* Processes one input sample `x` using `coeffs`, while using and updating
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* `state`. Returns the corresponding output sample.
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*
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* #### bw_lp1_process()
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* ```>>> */
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static inline void bw_lp1_process(
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bw_lp1_coeffs * BW_RESTRICT coeffs,
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bw_lp1_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_lp1_process_multi()
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* ```>>> */
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static inline void bw_lp1_process_multi(
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bw_lp1_coeffs * BW_RESTRICT coeffs,
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bw_lp1_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_lp1_set_cutoff()
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* ```>>> */
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static inline void bw_lp1_set_cutoff(
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bw_lp1_coeffs * BW_RESTRICT coeffs,
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float value);
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/*! <<<```
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* Sets the cutoff frequency `value` (Hz) in `coeffs`.
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*
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* Valid range: [`1e-6f`, `1e12f`].
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*
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* Default value: `1e3f`.
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*
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* #### bw_lp1_set_prewarp_at_cutoff()
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* ```>>> */
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static inline void bw_lp1_set_prewarp_at_cutoff(
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bw_lp1_coeffs * BW_RESTRICT coeffs,
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char value);
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/*! <<<```
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* Sets whether bilinear transform prewarping frequency should match the
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* cutoff frequency (non-`0`) or not (`0`).
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*
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* Default value: non-`0` (on).
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*
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* #### bw_lp1_set_prewarp_freq()
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* ```>>> */
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static inline void bw_lp1_set_prewarp_freq(
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bw_lp1_coeffs * BW_RESTRICT coeffs,
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float value);
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/*! <<<```
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* Sets the prewarping frequency `value` (Hz) in `coeffs`.
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*
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* Only used when the prewarp\_at\_cutoff parameter is off and however
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* internally limited to avoid instability.
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*
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* Valid range: [`1e-6f`, `1e12f`].
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*
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* Default value: `1e3f`.
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*
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* #### bw_lp1_coeffs_is_valid()
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* ```>>> */
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static inline char bw_lp1_coeffs_is_valid(
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const bw_lp1_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_lp1_coeffs`.
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*
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* #### bw_lp1_state_is_valid()
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* ```>>> */
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static inline char bw_lp1_state_is_valid(
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const bw_lp1_coeffs * BW_RESTRICT coeffs,
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const bw_lp1_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_lp1_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_lp1_coeffs_state {
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bw_lp1_coeffs_state_invalid,
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bw_lp1_coeffs_state_init,
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bw_lp1_coeffs_state_set_sample_rate,
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bw_lp1_coeffs_state_reset_coeffs
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};
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#endif
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struct bw_lp1_coeffs {
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#ifdef BW_DEBUG_DEEP
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uint32_t hash;
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enum bw_lp1_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_cutoff_state;
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bw_one_pole_state smooth_prewarp_freq_state;
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// Coefficients
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float t_k;
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float t;
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float X_x;
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float X_X_z1;
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float y_X;
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// Parameters
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float cutoff;
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float prewarp_k;
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float prewarp_freq;
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};
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struct bw_lp1_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 y_z1;
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float X_z1;
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};
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static inline void bw_lp1_init(
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bw_lp1_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->cutoff = 1e3f;
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coeffs->prewarp_k = 1.f;
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coeffs->prewarp_freq = 1e3f;
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#ifdef BW_DEBUG_DEEP
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coeffs->hash = bw_hash_sdbm("bw_lp1_coeffs");
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coeffs->state = bw_lp1_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_lp1_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state == bw_lp1_coeffs_state_init);
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}
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static inline void bw_lp1_set_sample_rate(
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bw_lp1_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_lp1_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state >= bw_lp1_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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coeffs->t_k = 3.141592653589793f / sample_rate;
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#ifdef BW_DEBUG_DEEP
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coeffs->state = bw_lp1_coeffs_state_set_sample_rate;
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#endif
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BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state == bw_lp1_coeffs_state_set_sample_rate);
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}
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static inline void bw_lp1_do_update_coeffs(
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bw_lp1_coeffs * BW_RESTRICT coeffs,
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char force) {
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const float prewarp_freq = coeffs->prewarp_freq + coeffs->prewarp_k * (coeffs->cutoff - coeffs->prewarp_freq);
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float prewarp_freq_cur = bw_one_pole_get_y_z1(&coeffs->smooth_prewarp_freq_state);
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float cutoff_cur = bw_one_pole_get_y_z1(&coeffs->smooth_cutoff_state);
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const char prewarp_freq_changed = force || prewarp_freq != prewarp_freq_cur;
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const char cutoff_changed = force || coeffs->cutoff != cutoff_cur;
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if (prewarp_freq_changed || cutoff_changed) {
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if (prewarp_freq_changed) {
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prewarp_freq_cur = bw_one_pole_process1_sticky_rel(&coeffs->smooth_coeffs, &coeffs->smooth_prewarp_freq_state, prewarp_freq);
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coeffs->t = bw_tanf(bw_minf(coeffs->t_k * prewarp_freq_cur, 1.567654734141306f)); // max = 0.499 * fs
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}
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if (cutoff_changed) {
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cutoff_cur = bw_one_pole_process1_sticky_rel(&coeffs->smooth_coeffs, &coeffs->smooth_cutoff_state, coeffs->cutoff);
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coeffs->y_X = bw_rcpf(cutoff_cur);
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}
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const float k = cutoff_cur * bw_rcpf(cutoff_cur * coeffs->t + prewarp_freq_cur);
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coeffs->X_x = k * prewarp_freq_cur;
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coeffs->X_X_z1 = k * coeffs->t;
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}
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}
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static inline void bw_lp1_reset_coeffs(
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bw_lp1_coeffs * BW_RESTRICT coeffs) {
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BW_ASSERT(coeffs != BW_NULL);
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BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_set_sample_rate);
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bw_one_pole_reset_state(&coeffs->smooth_coeffs, &coeffs->smooth_cutoff_state, coeffs->cutoff);
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bw_one_pole_reset_state(&coeffs->smooth_coeffs, &coeffs->smooth_prewarp_freq_state, coeffs->prewarp_freq + coeffs->prewarp_k * (coeffs->cutoff - coeffs->prewarp_freq));
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bw_lp1_do_update_coeffs(coeffs, 1);
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#ifdef BW_DEBUG_DEEP
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coeffs->state = bw_lp1_coeffs_state_reset_coeffs;
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coeffs->reset_id++;
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#endif
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BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state == bw_lp1_coeffs_state_reset_coeffs);
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}
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static inline float bw_lp1_reset_state(
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const bw_lp1_coeffs * BW_RESTRICT coeffs,
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bw_lp1_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_lp1_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state >= bw_lp1_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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(void)coeffs;
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const float y = x_0;
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state->y_z1 = x_0;
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state->X_z1 = 0.f;
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#ifdef BW_DEBUG_DEEP
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state->hash = bw_hash_sdbm("bw_lp1_state");
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state->coeffs_reset_id = coeffs->reset_id;
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#endif
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BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
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BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
BW_ASSERT_DEEP(bw_lp1_state_is_valid(coeffs, state));
|
|
BW_ASSERT(bw_is_finite(y));
|
|
|
|
return y;
|
|
}
|
|
|
|
static inline void bw_lp1_reset_state_multi(
|
|
const bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
bw_lp1_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_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_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_lp1_reset_state(coeffs, state[i], x_0[i]);
|
|
else
|
|
for (size_t i = 0; i < n_channels; i++)
|
|
bw_lp1_reset_state(coeffs, state[i], x_0[i]);
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
BW_ASSERT_DEEP(y_0 != BW_NULL ? bw_has_only_finite(y_0, n_channels) : 1);
|
|
}
|
|
|
|
static inline void bw_lp1_update_coeffs_ctrl(
|
|
bw_lp1_coeffs * BW_RESTRICT coeffs) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
|
|
(void)coeffs;
|
|
}
|
|
|
|
static inline void bw_lp1_update_coeffs_audio(
|
|
bw_lp1_coeffs * BW_RESTRICT coeffs) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
|
|
bw_lp1_do_update_coeffs(coeffs, 0);
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
}
|
|
|
|
static inline float bw_lp1_process1(
|
|
const bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
bw_lp1_state * BW_RESTRICT state,
|
|
float x) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
BW_ASSERT(state != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_state_is_valid(coeffs, state));
|
|
BW_ASSERT(bw_is_finite(x));
|
|
|
|
const float X = coeffs->X_x * (x - state->y_z1) - coeffs->X_X_z1 * state->X_z1;
|
|
const float y = x - coeffs->y_X * X;
|
|
state->y_z1 = y;
|
|
state->X_z1 = X;
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
BW_ASSERT_DEEP(bw_lp1_state_is_valid(coeffs, state));
|
|
BW_ASSERT(bw_is_finite(y));
|
|
|
|
return y;
|
|
}
|
|
|
|
static inline void bw_lp1_process(
|
|
bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
bw_lp1_state * BW_RESTRICT state,
|
|
const float * x,
|
|
float * y,
|
|
size_t n_samples) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
BW_ASSERT(state != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_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);
|
|
|
|
for (size_t i = 0; i < n_samples; i++) {
|
|
bw_lp1_update_coeffs_audio(coeffs);
|
|
y[i] = bw_lp1_process1(coeffs, state, x[i]);
|
|
}
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
BW_ASSERT_DEEP(bw_lp1_state_is_valid(coeffs, state));
|
|
BW_ASSERT_DEEP(bw_has_only_finite(y, n_samples));
|
|
}
|
|
|
|
static inline void bw_lp1_process_multi(
|
|
bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
bw_lp1_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_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_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
|
|
|
|
for (size_t i = 0; i < n_samples; i++) {
|
|
bw_lp1_update_coeffs_audio(coeffs);
|
|
for (size_t j = 0; j < n_channels; j++)
|
|
y[j][i] = bw_lp1_process1(coeffs, state[j], x[j][i]);
|
|
}
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_reset_coeffs);
|
|
}
|
|
|
|
static inline void bw_lp1_set_cutoff(
|
|
bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
float value) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_init);
|
|
BW_ASSERT(bw_is_finite(value));
|
|
BW_ASSERT(value >= 1e-6f && value <= 1e12f);
|
|
|
|
coeffs->cutoff = value;
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_init);
|
|
}
|
|
|
|
static inline void bw_lp1_set_prewarp_at_cutoff(
|
|
bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
char value) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_init);
|
|
|
|
coeffs->prewarp_k = value ? 1.f : 0.f;
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_init);
|
|
}
|
|
|
|
static inline void bw_lp1_set_prewarp_freq(
|
|
bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
float value) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_init);
|
|
BW_ASSERT(bw_is_finite(value));
|
|
BW_ASSERT(value >= 1e-6f && value <= 1e12f);
|
|
|
|
coeffs->prewarp_freq = value;
|
|
|
|
BW_ASSERT_DEEP(bw_lp1_coeffs_is_valid(coeffs));
|
|
BW_ASSERT_DEEP(coeffs->state >= bw_lp1_coeffs_state_init);
|
|
}
|
|
|
|
static inline char bw_lp1_coeffs_is_valid(
|
|
const bw_lp1_coeffs * BW_RESTRICT coeffs) {
|
|
BW_ASSERT(coeffs != BW_NULL);
|
|
|
|
#ifdef BW_DEBUG_DEEP
|
|
if (coeffs->hash != bw_hash_sdbm("bw_lp1_coeffs"))
|
|
return 0;
|
|
if (coeffs->state < bw_lp1_coeffs_state_init || coeffs->state > bw_lp1_coeffs_state_reset_coeffs)
|
|
return 0;
|
|
#endif
|
|
|
|
if (!bw_is_finite(coeffs->cutoff) || coeffs->cutoff < 1e-6f || coeffs->cutoff > 1e12f)
|
|
return 0;
|
|
if (!bw_is_finite(coeffs->prewarp_k) || (coeffs->prewarp_k != 0.f && coeffs->prewarp_k != 1.f))
|
|
return 0;
|
|
if (!bw_is_finite(coeffs->prewarp_freq) || coeffs->prewarp_freq < 1e-6f || coeffs->prewarp_freq > 1e12f)
|
|
return 0;
|
|
|
|
if (!bw_one_pole_coeffs_is_valid(&coeffs->smooth_coeffs))
|
|
return 0;
|
|
|
|
#ifdef BW_DEBUG_DEEP
|
|
if (coeffs->state >= bw_lp1_coeffs_state_set_sample_rate) {
|
|
if (!bw_is_finite(coeffs->t_k) || coeffs->t_k <= 0.f)
|
|
return 0;
|
|
}
|
|
|
|
if (coeffs->state >= bw_lp1_coeffs_state_reset_coeffs) {
|
|
if (!bw_is_finite(coeffs->t) || coeffs->t <= 0.f)
|
|
return 0;
|
|
if (!bw_is_finite(coeffs->y_X) || coeffs->y_X <= 0.f)
|
|
return 0;
|
|
if (!bw_is_finite(coeffs->X_x) || coeffs->X_x <= 0.f)
|
|
return 0;
|
|
if (!bw_is_finite(coeffs->X_X_z1) || coeffs->X_X_z1 <= 0.f)
|
|
return 0;
|
|
|
|
if (!bw_one_pole_state_is_valid(&coeffs->smooth_coeffs, &coeffs->smooth_cutoff_state))
|
|
return 0;
|
|
if (!bw_one_pole_state_is_valid(&coeffs->smooth_coeffs, &coeffs->smooth_prewarp_freq_state))
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
return 1;
|
|
}
|
|
|
|
static inline char bw_lp1_state_is_valid(
|
|
const bw_lp1_coeffs * BW_RESTRICT coeffs,
|
|
const bw_lp1_state * BW_RESTRICT state) {
|
|
BW_ASSERT(state != BW_NULL);
|
|
|
|
#ifdef BW_DEBUG_DEEP
|
|
if (state->hash != bw_hash_sdbm("bw_lp1_state"))
|
|
return 0;
|
|
|
|
if (coeffs != BW_NULL && coeffs->reset_id != state->coeffs_reset_id)
|
|
return 0;
|
|
#endif
|
|
|
|
(void)coeffs;
|
|
|
|
return bw_is_finite(state->y_z1) && bw_is_finite(state->X_z1);
|
|
}
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
|
|
#ifndef BW_CXX_NO_ARRAY
|
|
# include <array>
|
|
#endif
|
|
|
|
namespace Brickworks {
|
|
|
|
/*** Public C++ API ***/
|
|
|
|
/*! api_cpp {{{
|
|
* ##### Brickworks::LP1
|
|
* ```>>> */
|
|
template<size_t N_CHANNELS>
|
|
class LP1 {
|
|
public:
|
|
LP1();
|
|
|
|
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 setCutoff(
|
|
float value);
|
|
|
|
void setPrewarpAtCutoff(
|
|
bool value);
|
|
|
|
void setPrewarpFreq(
|
|
float 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_lp1_coeffs coeffs;
|
|
bw_lp1_state states[N_CHANNELS];
|
|
bw_lp1_state * BW_RESTRICT statesP[N_CHANNELS];
|
|
};
|
|
|
|
template<size_t N_CHANNELS>
|
|
inline LP1<N_CHANNELS>::LP1() {
|
|
bw_lp1_init(&coeffs);
|
|
for (size_t i = 0; i < N_CHANNELS; i++)
|
|
statesP[i] = states + i;
|
|
}
|
|
|
|
template<size_t N_CHANNELS>
|
|
inline void LP1<N_CHANNELS>::setSampleRate(
|
|
float sampleRate) {
|
|
bw_lp1_set_sample_rate(&coeffs, sampleRate);
|
|
}
|
|
|
|
template<size_t N_CHANNELS>
|
|
inline void LP1<N_CHANNELS>::reset(
|
|
float x0,
|
|
float * BW_RESTRICT y0) {
|
|
bw_lp1_reset_coeffs(&coeffs);
|
|
if (y0 != nullptr)
|
|
for (size_t i = 0; i < N_CHANNELS; i++)
|
|
y0[i] = bw_lp1_reset_state(&coeffs, states + i, x0);
|
|
else
|
|
for (size_t i = 0; i < N_CHANNELS; i++)
|
|
bw_lp1_reset_state(&coeffs, states + i, x0);
|
|
}
|
|
|
|
#ifndef BW_CXX_NO_ARRAY
|
|
template<size_t N_CHANNELS>
|
|
inline void LP1<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 LP1<N_CHANNELS>::reset(
|
|
const float * x0,
|
|
float * y0) {
|
|
bw_lp1_reset_coeffs(&coeffs);
|
|
bw_lp1_reset_state_multi(&coeffs, statesP, x0, y0, N_CHANNELS);
|
|
}
|
|
|
|
#ifndef BW_CXX_NO_ARRAY
|
|
template<size_t N_CHANNELS>
|
|
inline void LP1<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 LP1<N_CHANNELS>::process(
|
|
const float * const * x,
|
|
float * const * y,
|
|
size_t nSamples) {
|
|
bw_lp1_process_multi(&coeffs, statesP, x, y, N_CHANNELS, nSamples);
|
|
}
|
|
|
|
#ifndef BW_CXX_NO_ARRAY
|
|
template<size_t N_CHANNELS>
|
|
inline void LP1<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 LP1<N_CHANNELS>::setCutoff(
|
|
float value) {
|
|
bw_lp1_set_cutoff(&coeffs, value);
|
|
}
|
|
|
|
template<size_t N_CHANNELS>
|
|
inline void LP1<N_CHANNELS>::setPrewarpAtCutoff(
|
|
bool value) {
|
|
bw_lp1_set_prewarp_at_cutoff(&coeffs, value);
|
|
}
|
|
|
|
template<size_t N_CHANNELS>
|
|
inline void LP1<N_CHANNELS>::setPrewarpFreq(
|
|
float value) {
|
|
bw_lp1_set_prewarp_freq(&coeffs, value);
|
|
}
|
|
|
|
}
|
|
#endif
|
|
|
|
#endif
|