/* * Brickworks * * Copyright (C) 2023 Orastron Srl unipersonale * * Brickworks is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 3 of the License. * * Brickworks is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Brickworks. If not, see . * * File author: Stefano D'Angelo */ /*! * module_type {{{ dsp }}} * version {{{ 1.0.0 }}} * requires {{{ bw_common bw_gain bw_math bw_mm2 bw_one_pole bw_svf }}} * description {{{ * Second-order peak filter with unitary gain at DC and asymptotically * as frequency increases. * * The quality factor of the underlying bandpass filter can be either * directly controlled via the Q parameter or indirectly through the * bandwidth parameter, which designates the distance in octaves between * midpoint gain frequencies, i.e., frequencies with gain = peak gain / 2 in * dB terms. The use_bandiwdth parameter allows you to choose which * parameterization to use. * }}} * changelog {{{ * * }}} */ #ifndef BW_PEAK_H #define BW_PEAK_H #include #ifdef __cplusplus extern "C" { #endif /*! api {{{ * #### bw_peak_coeffs * ```>>> */ typedef struct bw_peak_coeffs bw_peak_coeffs; /*! <<<``` * Coefficients and related. * * #### bw_peak_state * ```>>> */ typedef struct bw_peak_state bw_peak_state; /*! <<<``` * Internal state and related. * * #### bw_peak_init() * ```>>> */ static inline void bw_peak_init(bw_peak_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Initializes input parameter values in `coeffs`. * * #### bw_peak_set_sample_rate() * ```>>> */ static inline void bw_peak_set_sample_rate(bw_peak_coeffs *BW_RESTRICT coeffs, float sample_rate); /*! <<<``` * Sets the `sample_rate` (Hz) value in `coeffs`. * * #### bw_peak_reset_coeffs() * ```>>> */ static inline void bw_peak_reset_coeffs(bw_peak_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Resets coefficients in `coeffs` to assume their target values. * * #### bw_peak_reset_state() * ```>>> */ static inline void bw_peak_reset_state(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, float x_0); /*! <<<``` * Resets the given `state` to its initial values using the given `coeffs` * and the quiescent/initial input value `x_0`. * * #### bw_peak_update_coeffs_ctrl() * ```>>> */ static inline void bw_peak_update_coeffs_ctrl(bw_peak_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Triggers control-rate update of coefficients in `coeffs`. * * #### bw_peak_update_coeffs_audio() * ```>>> */ static inline void bw_peak_update_coeffs_audio(bw_peak_coeffs *BW_RESTRICT coeffs); /*! <<<``` * Triggers audio-rate update of coefficients in `coeffs`. * * #### bw_peak_process1() * ```>>> */ static inline float bw_peak_process1(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, float x); /*! <<<``` * Processes one input sample `x` using `coeffs`, while using and updating * `state`. Returns the corresponding output sample. * * #### bw_peak_process() * ```>>> */ static inline void bw_peak_process(bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, const float *x, float *y, size_t n_samples); /*! <<<``` * Processes the first `n_samples` of the input buffer `x` and fills the * first `n_samples` of the output buffer `y`, while using and updating both * `coeffs` and `state` (control and audio rate). * * #### bw_peak_process_multi() * ```>>> */ static inline void bw_peak_process_multi(bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state * const *BW_RESTRICT state, const float * const *x, float **y, size_t n_channels, size_t n_samples); /*! <<<``` * Processes the first `n_samples` of the `n_channels` input buffers `x` and * fills the first `n_samples` of the `n_channels` output buffers `y`, while * using and updating both the common `coeffs` and each of the `n_channels` * `state`s (control and audio rate). * * #### bw_peak_set_cutoff() * ```>>> */ static inline void bw_peak_set_cutoff(bw_peak_coeffs *BW_RESTRICT coeffs, float value); /*! <<<``` * Sets the cutoff frequency `value` (Hz) in `coeffs`. * * Default value: `1e3f`. * * #### bw_peak_set_Q() * ```>>> */ static inline void bw_peak_set_Q(bw_peak_coeffs *BW_RESTRICT coeffs, float value); /*! <<<``` * Sets the quality factor to the given `value` in `coeffs`. * * `value` must be equal or bigger than `0.5f`. * * Default value: `0.5f`. * * #### bw_peak_set_peak_gain_lin() * ```>>> */ static inline void bw_peak_set_peak_gain_lin(bw_peak_coeffs *BW_RESTRICT coeffs, float value); /*! <<<``` * Sets the peak gain parameter to the given `value` (linear gain) in * `coeffs`. * * Default value: `0.f`. * * #### bw_peak_set_peak_gain_dB() * ```>>> */ static inline void bw_peak_set_peak_gain_dB(bw_peak_coeffs *BW_RESTRICT coeffs, float value); /*! <<<``` * Sets the peak gain parameter to the given `value` (dB) in `coeffs`. * * Default value: `-INFINITY`. * * #### bw_peak_set_bandiwdth() * ```>>> */ static inline void bw_peak_set_bandwidth(bw_peak_coeffs *BW_RESTRICT coeffs, float value); /*! <<<``` * Sets the bandwidth `value` (octaves) in `coeffs`. * * Default value: `0.5f`. * * #### bw_peak_set_use_bandwidth() * ```>>> */ static inline void bw_peak_set_use_bandwidth(bw_peak_coeffs *BW_RESTRICT coeffs, char value); /*! <<<``` * Sets whether the quality factor should be controlled via the bandwidth * parameter (`value` non-`0`) or via the Q parameter (`0`). * * Default value: non-`0` (use bandwidth parameter). * }}} */ #ifdef __cplusplus } #endif /*** 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 #ifdef __cplusplus extern "C" { #endif struct bw_peak_coeffs { // Sub-components bw_mm2_coeffs mm2_coeffs; // Coefficients float bw_k; // Parameters float peak_gain; float Q; float bandwidth; char use_bandwidth; int param_changed; }; struct bw_peak_state { bw_mm2_state mm2_state; }; #define BW_PEAK_PARAM_PEAK_GAIN 1 #define BW_PEAK_PARAM_Q (1<<1) #define BW_PEAK_PARAM_BANDWIDTH (1<<2) static inline void bw_peak_init(bw_peak_coeffs *BW_RESTRICT coeffs) { bw_mm2_init(&coeffs->mm2_coeffs); coeffs->peak_gain = 1.f; coeffs->Q = 0.5f; coeffs->bandwidth = 2.543106606327224f; coeffs->use_bandwidth = 1; } static inline void bw_peak_set_sample_rate(bw_peak_coeffs *BW_RESTRICT coeffs, float sample_rate) { bw_mm2_set_sample_rate(&coeffs->mm2_coeffs, sample_rate); } static inline void bw_peak_update_mm2_params(bw_peak_coeffs *BW_RESTRICT coeffs) { if (coeffs->param_changed) { if (coeffs->use_bandwidth) { if (coeffs->param_changed & (BW_PEAK_PARAM_PEAK_GAIN | BW_PEAK_PARAM_BANDWIDTH)) { if (coeffs->param_changed & BW_PEAK_PARAM_BANDWIDTH) coeffs->bw_k = bw_pow2f(coeffs->bandwidth); const float Q = bw_sqrtf(coeffs->bw_k * coeffs->peak_gain) * bw_rcpf(coeffs->bw_k - 1.f); bw_mm2_set_Q(&coeffs->mm2_coeffs, Q); bw_mm2_set_coeff_bp(&coeffs->mm2_coeffs, (coeffs->peak_gain - 1.f) * bw_rcpf(Q)); } } else { if (coeffs->param_changed & (BW_PEAK_PARAM_PEAK_GAIN | BW_PEAK_PARAM_Q)) { if (coeffs->param_changed & BW_PEAK_PARAM_Q) bw_mm2_set_Q(&coeffs->mm2_coeffs, coeffs->Q); bw_mm2_set_coeff_bp(&coeffs->mm2_coeffs, (coeffs->peak_gain - 1.f) * bw_rcpf(coeffs->Q)); } } coeffs->param_changed = 0; } } static inline void bw_peak_reset_coeffs(bw_peak_coeffs *BW_RESTRICT coeffs) { coeffs->param_changed = ~0; bw_peak_update_mm2_params(coeffs); bw_mm2_reset_coeffs(&coeffs->mm2_coeffs); } static inline void bw_peak_reset_state(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, float x_0) { bw_mm2_reset_state(&coeffs->mm2_coeffs, &state->mm2_state, x_0); } static inline void bw_peak_update_coeffs_ctrl(bw_peak_coeffs *BW_RESTRICT coeffs) { bw_peak_update_mm2_params(coeffs); bw_mm2_update_coeffs_ctrl(&coeffs->mm2_coeffs); } static inline void bw_peak_update_coeffs_audio(bw_peak_coeffs *BW_RESTRICT coeffs) { bw_mm2_update_coeffs_audio(&coeffs->mm2_coeffs); } static inline float bw_peak_process1(const bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, float x) { return bw_mm2_process1(&coeffs->mm2_coeffs, &state->mm2_state, x); } static inline void bw_peak_process(bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state *BW_RESTRICT state, const float *x, float *y, size_t n_samples) { bw_peak_update_coeffs_ctrl(coeffs); for (size_t i = 0; i < n_samples; i++) { bw_peak_update_coeffs_audio(coeffs); y[i] = bw_peak_process1(coeffs, state, x[i]); } } static inline void bw_peak_process_multi(bw_peak_coeffs *BW_RESTRICT coeffs, bw_peak_state * const *BW_RESTRICT state, const float * const *x, float **y, size_t n_channels, size_t n_samples) { bw_peak_update_coeffs_ctrl(coeffs); for (size_t i = 0; i < n_samples; i++) { bw_peak_update_coeffs_audio(coeffs); for (size_t j = 0; j < n_channels; j++) y[j][i] = bw_peak_process1(coeffs, state[j], x[j][i]); } } static inline void bw_peak_set_cutoff(bw_peak_coeffs *BW_RESTRICT coeffs, float value) { bw_mm2_set_cutoff(&coeffs->mm2_coeffs, value); } static inline void bw_peak_set_Q(bw_peak_coeffs *BW_RESTRICT coeffs, float value) { if (coeffs->Q != value) { coeffs->Q = value; coeffs->param_changed |= BW_PEAK_PARAM_Q; } } static inline void bw_peak_set_peak_gain_lin(bw_peak_coeffs *BW_RESTRICT coeffs, float value) { if (coeffs->peak_gain != value) { coeffs->peak_gain = value; coeffs->param_changed |= BW_PEAK_PARAM_PEAK_GAIN; } } static inline void bw_peak_set_peak_gain_dB(bw_peak_coeffs *BW_RESTRICT coeffs, float value) { bw_peak_set_peak_gain_lin(coeffs, bw_dB2linf(value)); } static inline void bw_peak_set_bandwidth(bw_peak_coeffs *BW_RESTRICT coeffs, float value) { if (coeffs->bandwidth != value) { coeffs->bandwidth = value; coeffs->param_changed |= BW_PEAK_PARAM_BANDWIDTH; } } static inline void bw_peak_set_use_bandwidth(bw_peak_coeffs *BW_RESTRICT coeffs, char value) { if ((coeffs->use_bandwidth && !value) || (!coeffs->use_bandwidth && value)) { coeffs->use_bandwidth = value; coeffs->param_changed |= BW_PEAK_PARAM_Q | BW_PEAK_PARAM_BANDWIDTH; } } #undef BW_PEAK_PARAM_PEAK_GAIN #undef BW_PEAK_PARAM_Q #undef BW_PEAK_PARAM_BANDWIDTH #ifdef __cplusplus } #include namespace Brickworks { /*** Public C++ API ***/ /*! api_cpp {{{ * ##### Brickworks::Peak * ```>>> */ template class Peak { public: Peak(); void setSampleRate(float sampleRate); void reset(float x_0 = 0.f); void process( const float * const *x, float **y, size_t nSamples); void process( std::array x, std::array y, size_t nSamples); void setCutoff(float value); void setQ(float value); void setPeakGainLin(float value); void setPeakGainDB(float value); void setBandwidth(float value); void setUseBandwidth(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_peak_coeffs coeffs; bw_peak_state states[N_CHANNELS]; bw_peak_state *statesP[N_CHANNELS]; }; template inline Peak::Peak() { bw_peak_init(&coeffs); for (size_t i = 0; i < N_CHANNELS; i++) statesP[i] = states + i; } template inline void Peak::setSampleRate(float sampleRate) { bw_peak_set_sample_rate(&coeffs, sampleRate); } template inline void Peak::reset(float x_0) { bw_peak_reset_coeffs(&coeffs); for (size_t i = 0; i < N_CHANNELS; i++) bw_peak_reset_state(&coeffs, states + i, x_0); } template inline void Peak::process( const float * const *x, float **y, size_t nSamples) { bw_peak_process_multi(&coeffs, statesP, x, y, N_CHANNELS, nSamples); } template inline void Peak::process( std::array x, std::array y, size_t nSamples) { process(x.data(), y.data(), nSamples); } template inline void Peak::setCutoff(float value) { bw_peak_set_cutoff(&coeffs, value); } template inline void Peak::setQ(float value) { bw_peak_set_Q(&coeffs, value); } template inline void Peak::setPeakGainLin(float value) { bw_peak_set_peak_gain_lin(&coeffs, value); } template inline void Peak::setPeakGainDB(float value) { bw_peak_set_peak_gain_dB(&coeffs, value); } template inline void Peak::setBandwidth(float value) { bw_peak_set_bandwidth(&coeffs, value); } template inline void Peak::setUseBandwidth(bool value) { bw_peak_set_use_bandwidth(&coeffs, value); } } #endif #endif