sbl::dsp::EnvelopeFollower Class Reference

#include <envelope_follower.hpp>

Collaboration diagram for sbl::dsp::EnvelopeFollower:

Public Member Functions
void	set_times (float attack_ms, float release_ms, uint32_t sample_rate)
	Set attack and release times in milliseconds.
void	set_coefficients (float attack, float release)
	Set attack and release coefficients directly.
float	process (float sample)
	Process a single sample, return envelope value.
void	process (const float *in, float *out, uint16_t frames)
	Process a block, write envelope to output buffer.
float	value () const
	Current envelope value (can be read without processing)
void	reset ()
	Reset envelope state to zero.
void	reset (float initial)
	Reset envelope state to a specific value.

Detailed Description

Definition at line 23 of file envelope_follower.hpp.

Member Function Documentation

process() [1/2]

void sbl::dsp::EnvelopeFollower::process ( const float *  in, float *  out, uint16_t  frames  )

inline

Process a block, write envelope to output buffer.

Input and output can be the same buffer (in-place).

Parameters

in	Input audio buffer
out	Output envelope buffer (always >= 0)
frames	Number of samples

Definition at line 105 of file envelope_follower.hpp.

References process().

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process() [2/2]

float sbl::dsp::EnvelopeFollower::process ( float  sample )

inline

Process a single sample, return envelope value.

Full-wave rectifies the input, then applies asymmetric smoothing: if |input| > state: use attack coefficient (rise fast) if |input| < state: use release coefficient (fall slow)

Parameters

sample

Input audio sample

Returns

Current envelope value (always >= 0)

Definition at line 85 of file envelope_follower.hpp.

Referenced by process().

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reset() [1/2]

void sbl::dsp::EnvelopeFollower::reset ( )

inline

Reset envelope state to zero.

Definition at line 115 of file envelope_follower.hpp.

reset() [2/2]

void sbl::dsp::EnvelopeFollower::reset ( float  initial )

inline

Reset envelope state to a specific value.

Definition at line 118 of file envelope_follower.hpp.

set_coefficients()

void sbl::dsp::EnvelopeFollower::set_coefficients ( float  attack, float  release  )

inline

Set attack and release coefficients directly.

Coefficient range [0.0, 1.0). Higher = faster response. 0.0 = no change (hold forever), approaching 1.0 = instant.

Parameters

attack	Attack coefficient
release	Release coefficient

Definition at line 70 of file envelope_follower.hpp.

set_times()

void sbl::dsp::EnvelopeFollower::set_times ( float  attack_ms, float  release_ms, uint32_t  sample_rate  )

inline

Set attack and release times in milliseconds.

Note

All public methods are ISR-safe — bounded computation, no I/O.

Computes one-pole coefficients from time constants. Attack: how fast the follower rises to meet a transient. Release: how fast it falls after the signal drops.

Parameters

attack_ms	Attack time in milliseconds (typically 0.1–10)
release_ms	Release time in milliseconds (typically 50–500)
sample_rate	Audio sample rate (e.g. 48000)

Definition at line 38 of file envelope_follower.hpp.

value()

float sbl::dsp::EnvelopeFollower::value ( ) const

inline

Current envelope value (can be read without processing)

Definition at line 112 of file envelope_follower.hpp.

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The documentation for this class was generated from the following file:

• src/sbl/dsp/envelope_follower.hpp