Brickworks > API documentation > bw_noise_gate

bw_noise_gate

Description

Noise gate with independent sidechain input.

Info

Module type: dsp

Version: 1.1.0

Requires:

API

bw_noise_gate_coeffs

typedef struct bw_noise_gate_coeffs bw_noise_gate_coeffs;

Coefficients and related.

bw_noise_gate_state

typedef struct bw_noise_gate_state bw_noise_gate_state;

Internal state and related.

bw_noise_gate_init()

static inline void bw_noise_gate_init(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs);

Initializes input parameter values in coeffs.

bw_noise_gate_set_sample_rate()

static inline void bw_noise_gate_set_sample_rate(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	float                              sample_rate);

Sets the sample_rate (Hz) value in coeffs.

bw_noise_gate_reset_coeffs()

static inline void bw_noise_gate_reset_coeffs(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs);

Resets coefficients in coeffs to assume their target values.

bw_noise_gate_reset_state()

static inline float bw_noise_gate_reset_state(
	const bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	bw_noise_gate_state * BW_RESTRICT        state,
	float                                    x_0,
	float                                    x_sc_0);

Resets the given state to its initial values using the given coeffs and the initial input value x_0 and sidechain input value x_sc_0.

Returns the corresponding initial output value.

bw_noise_gate_reset_state_multi()

static inline void bw_noise_gate_reset_state_multi(
	const bw_noise_gate_coeffs * BW_RESTRICT              coeffs,
	bw_noise_gate_state * BW_RESTRICT const * BW_RESTRICT state,
	const float *                                         x_0,
	const float *                                         x_sc_0,
	float *                                               y_0,
	size_t                                                n_channels);

Resets each of the n_channels states to its initial values using the given coeffs and the corresponding initial input value in the x_0 array and sidechain input value in the x_sc_0 array.

The corresponding initial output values are written into the y_0 array, if not BW_NULL.

If x_sc_0 is BW_NULL the initial sidechain input values are assumed to be 0.f.

bw_noise_gate_update_coeffs_ctrl()

static inline void bw_noise_gate_update_coeffs_ctrl(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs);

Triggers control-rate update of coefficients in coeffs.

bw_noise_gate_update_coeffs_audio()

static inline void bw_noise_gate_update_coeffs_audio(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs);

Triggers audio-rate update of coefficients in coeffs.

bw_noise_gate_process1()

static inline float bw_noise_gate_process1(
	const bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	bw_noise_gate_state * BW_RESTRICT        state,
	float                                    x,
	float                                    x_sc);

Processes one input sample x and the corresponding sidechain input sample x_sc using coeffs, while using and updating state. Returns the corresponding output sample.

bw_noise_gate_process()

static inline void bw_noise_gate_process(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	bw_noise_gate_state * BW_RESTRICT  state,
	const float *                      x,
	const float *                      x_sc,
	float *                            y,
	size_t                             n_samples);

Processes the first n_samples of the input buffer x and the first n_samples of the sidechain input buffer x_sc, and fills the first n_samples of the output buffer y, while using and updating both coeffs and state (control and audio rate).

If x_sc is BW_NULL it behaves as if a zero-filled buffer was passed instead.

bw_noise_gate_process_multi()

static inline void bw_noise_gate_process_multi(
	bw_noise_gate_coeffs * BW_RESTRICT                    coeffs,
	bw_noise_gate_state * BW_RESTRICT const * BW_RESTRICT state,
	const float * const *                                 x,
	const float * const *                                 x_sc,
	float * const *                                       y,
	size_t                                                n_channels,
	size_t                                                n_samples);

Processes the first n_samples of the n_channels input buffers x and the first n_samples of the n_channels sidechain input buffers x_sc, 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 states (control and audio rate).

If x_sc is BW_NULL it behaves as if zero-filled buffers were passed instead.

bw_noise_gate_set_thresh_lin()

static inline void bw_noise_gate_set_thresh_lin(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	float                              value);

Sets the threshold value (linear) in coeffs.

Valid range: [1e-20f, 1e20f].

Default value: 1.f.

bw_noise_gate_set_thresh_dBFS()

static inline void bw_noise_gate_set_thresh_dBFS(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	float                              value);

Sets the threshold value (dBFS) in coeffs.

Valid range: [-400.f, 400.f].

Default value: 0.f.

bw_noise_gate_set_ratio()

static inline void bw_noise_gate_set_ratio(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	float                              value);

Sets the copmpression ratio value in coeffs.

value is actually the slope of the gain curve below the threshold, hence 1.f means no gating and INIFINITY leads to a hard gate.

value must be greater than or equal to 1.f.

Default value: 1.f.

bw_noise_gate_set_attack_tau()

static inline void bw_noise_gate_set_attack_tau(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	float                              value);

Sets the attack time constant value (s) in coeffs.

value must be non-negative.

Default value: 0.f.

bw_noise_gate_set_release_tau()

static inline void bw_noise_gate_set_release_tau(
	bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	float                              value);

Sets the release time constant value (s) in coeffs.

value must be non-negative.

Default value: 0.f.

bw_noise_gate_coeffs_is_valid()

static inline char bw_noise_gate_coeffs_is_valid(
	const bw_noise_gate_coeffs * BW_RESTRICT coeffs);

Tries to determine whether coeffs is valid and returns non-0 if it seems to be the case and 0 if it is certainly not. False positives are possible, false negatives are not.

coeffs must at least point to a readable memory block of size greater than or equal to that of bw_noise_gate_coeffs.

bw_noise_gate_state_is_valid()

static inline char bw_noise_gate_state_is_valid(
	const bw_noise_gate_coeffs * BW_RESTRICT coeffs,
	const bw_noise_gate_state * BW_RESTRICT  state);

Tries to determine whether state is valid and returns non-0 if it seems to be the case and 0 if it is certainly not. False positives are possible, false negatives are not.

If coeffs is not BW_NULL extra cross-checks might be performed (state is supposed to be associated to coeffs).

state must at least point to a readable memory block of size greater than or equal to that of bw_noise_gate_state.

C++ wrapper

Brickworks::NoiseGate
template<size_t N_CHANNELS>
class NoiseGate {
public:
	NoiseGate();

	void setSampleRate(
		float sampleRate);

	void reset(
		float               x0 = 0.f,
		float               xSc0 = 0.f,
		float * BW_RESTRICT y0 = nullptr);

#ifndef BW_CXX_NO_ARRAY
	void reset(
		float                                       x0,
		float                                       xSc0,
		std::array<float, N_CHANNELS> * BW_RESTRICT y0);
#endif

	void reset(
		const float * x0,
		const float * xSc0,
		float *       y0 = nullptr);

#ifndef BW_CXX_NO_ARRAY
	void reset(
		std::array<float, N_CHANNELS>               x0,
		std::array<float, N_CHANNELS>               xSc0,
		std::array<float, N_CHANNELS> * BW_RESTRICT y0 = nullptr);
#endif

	void process(
		const float * const * x,
		const float * const * xSc,
		float * const *       y,
		size_t                nSamples);

#ifndef BW_CXX_NO_ARRAY
	void process(
		std::array<const float *, N_CHANNELS> x,
		std::array<const float *, N_CHANNELS> xSc,
		std::array<float *, N_CHANNELS>       y,
		size_t                                nSamples);
#endif

	// >> the following 2 methods only exist because of a typo, don't use
	void setTreshLin(
		float value);

	void setTreshDBFS(
		float value);
	// <<

	void setThreshLin(
		float value);

	void setThreshDBFS(
		float value);

	void setRatio(
		float value);

	void setAttackTau(
		float value);

	void setReleaseTau(
		float value);
...
}

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