/* * Brickworks * * Copyright (C) 2022 Orastron Srl unipersonale * * Brickworks is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 3 of the License. * * Brickworks is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Brickworks. If not, see . * * File author: Stefano D'Angelo */ /*! * module_type {{{ dsp }}} * version {{{ 0.2.0 }}} * requires {{{ bw_config bw_common bw_math bw_one_pole }}} * description {{{ * Envelope follower made of a full-wave rectifier followed by * [bw_one_pole](bw_one_pole) one-pole filter (6 dB/oct). * }}} * changelog {{{ * * }}} */ #ifndef _BW_ENV_FOLLOW_H #define _BW_ENV_FOLLOW_H #ifdef __cplusplus extern "C" { #endif #include /*! api {{{ * #### bw_env_follow_coeffs * ```>>> */ typedef struct _bw_env_follow_coeffs bw_env_follow_coeffs; /*! <<<``` * Coefficients and related. * * #### bw_env_follow_state * ```>>> */ typedef struct _bw_env_follow_state bw_env_follow_state; /*! <<<``` * Internal state and related. * * #### bw_env_follow_init() * ```>>> */ static inline void bw_env_follow_init(bw_env_follow_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Initializes input parameter values in `coeffs`. * * #### bw_env_follow_set_sample_rate() * ```>>> */ static inline void bw_env_follow_set_sample_rate(bw_env_follow_coeffs *BW_RESTRICT coeffs, float sample_rate); /*! <<<``` * Sets the `sample_rate` (Hz) value in `coeffs`. * * #### bw_env_follow_reset_coeffs() * ```>>> */ static inline void bw_env_follow_reset_coeffs(bw_env_follow_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Resets coefficients in `coeffs` to assume their target values. * * #### bw_env_follow_reset_state() * ```>>> */ static inline void bw_env_follow_reset_state(const bw_env_follow_coeffs *BW_RESTRICT coeffs, bw_env_follow_state *BW_RESTRICT state); /*! <<<``` * Resets the given `state` to its initial values using the given `coeffs`. * * #### bw_env_follow_update_coeffs_ctrl() * ```>>> */ static inline void bw_env_follow_update_coeffs_ctrl(bw_env_follow_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Triggers control-rate update of coefficients in `coeffs`. * * #### bw_env_follow_update_coeffs_audio() * ```>>> */ static inline void bw_env_follow_update_coeffs_audio(bw_env_follow_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Triggers audio-rate update of coefficients in `coeffs`. * * #### bw_env_follow_process1() * ```>>> */ static inline float bw_env_follow_process1(const bw_env_follow_coeffs *BW_RESTRICT coeffs, bw_env_follow_state *BW_RESTRICT state, float x); /*! <<<``` * Processes one input sample `x` using `coeffs`, while using and updating * `state`. Returns the corresponding output sample. * * #### bw_env_follow_process() * ```>>> */ static inline void bw_env_follow_process(bw_env_follow_coeffs *BW_RESTRICT coeffs, bw_env_follow_state *BW_RESTRICT state, const float *x, float *y, int n_samples); /*! <<<``` * Processes the first `n_samples` of the input buffer `x` and fills the * first `n_samples` of the output buffer `y`, while using and updating both * `coeffs` and `state` (control and audio rate). * * `y` may be `NULL`. * * #### bw_env_follow_set_attack_tau() * ```>>> */ static inline void bw_env_follow_set_attack_tau(bw_env_follow_coeffs *BW_RESTRICT coeffs, float value); /*! <<<``` * Sets the upgoing (attack) time constant in `coeffs` of the one-pole filter * to `value` (s). * * Default value: `0.f`. * * #### bw_env_follow_set_release_tau() * ```>>> */ static inline void bw_env_follow_set_release_tau(bw_env_follow_coeffs *BW_RESTRICT coeffs, float value); /*! <<<``` * Sets the downgoing (release) time constant in `coeffs` of the one-pole * filter to `value` (s). * * Default value: `0.f`. * * #### bw_env_follow_get_y_z1() * ```>>> */ static inline float bw_env_follow_get_y_z1(const bw_env_follow_state *BW_RESTRICT state); /*! <<<``` * Returns the last output sample as stored in `state`. * }}} */ /*** Implementation ***/ /* WARNING: This part of the file is not part of the public API. Its content may * change at any time in future versions. Please, do not use it directly. */ #include #include struct _bw_env_follow_coeffs { // Sub-components bw_one_pole_coeffs one_pole_coeffs; }; struct _bw_env_follow_state { bw_one_pole_state one_pole_state; }; static inline void bw_env_follow_init(bw_env_follow_coeffs *BW_RESTRICT coeffs) { bw_one_pole_init(&coeffs->one_pole_coeffs); } static inline void bw_env_follow_set_sample_rate(bw_env_follow_coeffs *BW_RESTRICT coeffs, float sample_rate) { bw_one_pole_set_sample_rate(&coeffs->one_pole_coeffs, sample_rate); } static inline void bw_env_follow_reset_coeffs(bw_env_follow_coeffs *BW_RESTRICT coeffs) { bw_one_pole_reset_coeffs(&coeffs->one_pole_coeffs); } static inline void bw_env_follow_reset_state(const bw_env_follow_coeffs *BW_RESTRICT coeffs, bw_env_follow_state *BW_RESTRICT state) { bw_one_pole_reset_state(&coeffs->one_pole_coeffs, &state->one_pole_state, 0.f); } static inline void bw_env_follow_update_coeffs_ctrl(bw_env_follow_coeffs *BW_RESTRICT coeffs) { bw_one_pole_update_coeffs_ctrl(&coeffs->one_pole_coeffs); } static inline void bw_env_follow_update_coeffs_audio(bw_env_follow_coeffs *BW_RESTRICT coeffs) { bw_one_pole_update_coeffs_audio(&coeffs->one_pole_coeffs); } static inline float bw_env_follow_process1(const bw_env_follow_coeffs *BW_RESTRICT coeffs, bw_env_follow_state *BW_RESTRICT state, float x) { x = bw_absf(x); return bw_one_pole_process1_asym(&coeffs->one_pole_coeffs, &state->one_pole_state, x); } static inline void bw_env_follow_process(bw_env_follow_coeffs *BW_RESTRICT coeffs, bw_env_follow_state *BW_RESTRICT state, const float *x, float *y, int n_samples) { bw_env_follow_update_coeffs_ctrl(coeffs); if (y != NULL) for (int i = 0; i < n_samples; i++) { bw_env_follow_update_coeffs_audio(coeffs); y[i] = bw_env_follow_process1(coeffs, state, x[i]); } else for (int i = 0; i < n_samples; i++) { bw_env_follow_update_coeffs_audio(coeffs); bw_env_follow_process1(coeffs, state, x[i]); } } static inline void bw_env_follow_set_attack_tau(bw_env_follow_coeffs *BW_RESTRICT coeffs, float value) { bw_one_pole_set_tau_up(&coeffs->one_pole_coeffs, value); } static inline void bw_env_follow_set_release_tau(bw_env_follow_coeffs *BW_RESTRICT coeffs, float value) { bw_one_pole_set_tau_down(&coeffs->one_pole_coeffs, value); } static inline float bw_env_follow_get_y_z1(const bw_env_follow_state *BW_RESTRICT state) { return bw_one_pole_get_y_z1(&state->one_pole_state); } #ifdef __cplusplus } #endif #endif