Main namespace for the DSPark framework. More...

Namespaces
namespace	AnalogRandom

namespace	detail

namespace	harmony

namespace	plugin

namespace	simd

namespace	Smoothers

namespace	wdf

Classes
class	ADSREnvelope
	Classic ADSR envelope generator with exponential curves. More...

class	AlgorithmicReverb
	True-stereo 32-line FDN reverb with exact per-band decay and 6 presets. More...

class	AudioBuffer
	Owning audio buffer with contiguous, 32-byte aligned storage. More...

class	AudioBufferView
	Non-owning view over audio channel data. More...

class	AudioFile
	Abstract base class for audio file readers and writers. More...

struct	AudioFileInfo
	Metadata describing an audio file's format and dimensions. More...

class	AudioIntervalAnalyzer
	One requested mono/stereo interval per instance; feed several instances the same blocks to measure overlapping intervals in one source pass. The region is always measured as an independent finite fragment. Optional continuous loudness observations are separate, explicitly scoped results; they never replace or masquerade as the region's integrated loudness. More...

struct	AudioSpec
	Describes the audio environment for a DSP processor. More...

class	AutoGain
	Block-adaptive automatic gain compensation with SIMD-friendly linear interpolation. More...

class	BeatTracker
	Tempo and beat tracking with an offline grid and a causal readout. More...

class	Biquad
	Biquad filter using Transposed Direct Form II (TDF-II) with thread-safe updates. More...

struct	BiquadCoeffs
	Stores normalised biquad coefficients (b0, b1, b2, a1, a2), always double. More...

class	ChordDetector
	Monophonic-buffer chord recognition with confidence gating. More...

class	Chorus
	Multi-voice chorus/flanger with true stereo spread and smooth parameter handling. More...

class	Clipper
	Real-time audio clipper with analog modeling and anti-aliasing features. More...

class	Compressor
	High-fidelity modular compressor designed for real-time applications. More...

class	Convolver
	Real-time partitioned convolution using overlap-save with FFT. More...

class	Crossfade
	Artifact-free, SIMD-friendly crossfader for two audio signals. More...

class	CrossoverFilter
	Linkwitz-Riley crossover with 2-12 bands, LR12/LR24/LR48. More...

class	DCBlocker
	DC blocking filter with configurable Butterworth order (1-10). More...

class	DeEsser
	Stereo-linked, CPU-optimized dynamic-EQ de-esser. More...

class	Delay

class	DelayEstimator
	Streaming GCC-PHAT delay estimator with sub-sample refinement. More...

class	DenormalGuard
	RAII scope guard to disable denormalised (subnormal) floating-point numbers. More...

class	Dither
	TPDF dithering processor with optional 1st-order noise shaping. More...

class	DryWetMixer
	Pre-allocated, SIMD-friendly dry/wet blender for real-time audio. More...

class	DynamicEQ
	Dynamic parametric EQ with dual above/below threshold per band. More...

class	EnvelopeFollower
	Attack/release envelope detector (Peak or RMS). More...

class	Equalizer
	Parametric multi-band EQ using cascaded biquads or FFT overlap-save convolution. More...

class	Expander
	Downward expander with ratio control, hysteresis, and sidechain. More...

class	FFTComplex
	Complex FFT on interleaved data (Stockham radix-4 engine, SIMD). More...

class	FFTReal
	FFT optimised for real-valued input signals (the common audio case). More...

class	FilterEngine
	Professional multi-mode filter with cascaded biquad stages. More...

class	FIRDesign
	Static methods for designing FIR filter coefficients. More...

class	FIRFilter
	FIR filter using direct-form convolution with a mirrored delay line. More...

class	FlacFile
	Decode-only native FLAC implementation with eager integrity checks. More...

class	FrequencyShifter
	Constant-Hz frequency shift optimized via Quadrature Oscillator. More...

class	Gain
	Professional click-free gain processor. More...

class	Goertzel
	Single-frequency magnitude detector using the Goertzel algorithm. More...

class	GranularProcessor
	Granular clouds and spectral-freeze textures from live input. More...

class	Hilbert
	90-degree phase-differencing network (analytic-signal generator). More...

class	HilbertIIR
	Zero-latency analytic pair from two allpass chains (a 90-degree phase-difference network). More...

class	Hysteresis
	Per-channel Jiles-Atherton hysteresis processor (field in, M out). More...

class	KeyDetector
	Key estimation by profile correlation over an accumulated chroma. More...

class	LadderFilter
	4-pole resonant ladder filter (Moog topology, TPT discretization). More...

class	LevelFollower
	Per-channel peak and RMS envelope follower with lock-free readout. More...

class	Limiter
	High-performance brickwall lookahead limiter. More...

class	LoopFinder
	Finds and renders bounded, deterministic loop seams. More...

class	LoudnessMeter
	Real-time safe EBU R128 loudness meter. More...

class	LoudnessNormalizer
	Offline waveform-preserving LUFS normalizer with a hard true-peak ceiling. More...

struct	MidiEvent
	One semantic SMF event with a delta time. More...

class	MidiFile
	Transactional, resource-bounded SMF parser and authoring API. More...

struct	MidiTempoChange
	Effective tempo at an absolute tick. More...

struct	MidiTrack
	Ordered events belonging to one SMF track chunk. More...

struct	MidSide
	Static utility for Mid/Side stereo encoding and decoding. More...

class	MinBlepTable
	Shared minimum-phase band-limited step (minBLEP) residual table. More...

class	ModulationRouter
	Fixed-capacity source-to-target router with per-route depth/smoothing. More...

class	Mp3File

class	MultibandCompressor
	Multi-band compressor: crossover split, per-band compression, sum. More...

class	NoiseGate
	High-performance noise gate with state machine, hysteresis, and zero-allocation processing. More...

class	NoiseGenerator
	Generates decorellated noise (white, pink, brown) across multiple channels. More...

class	OfflineAudioSink
	Transactional worker sink for arbitrarily long offline output. More...

class	OfflineAudioSource
	Rewindable, complete-file source with int64 positions and bounded blocks. More...

struct	OfflineAudioSpec
	Immutable source format and host-provided content/timeline identity. More...

class	OfflineBeatCompressor
	Complete-source pulse compression with one positive reduction-dB control. More...

class	OfflineBufferSource
	Borrowed planar-buffer adapter; does not allocate, copy or own input. More...

class	OfflineEnergyAnalyzer
	Complete-file fixed-duration energy analysis for offline processors. More...

struct	OfflineFingerprint
	Noncryptographic PCM fingerprint, stable across block divisions. More...

struct	OfflineGainRenderInfo
	Measured-render control adjustments; no clipping or master gain trim. More...

class	OfflineHardClipper
	OFFLINE ONLY: calibrates an antialiased hard curve on the complete source. More...

struct	OfflineJobOptions
	Resource and cooperative-cancellation controls for one worker operation. More...

class	OfflineLeveler
	Complete-file automatic upward leveling, with reusable immutable plans. More...

class	OfflinePeakCompressor
	Complete-file peak compressor with a positive reduction-dB control. More...

struct	OfflineProgress
	Worker progress in source frames, or control points in the Plan pass. More...

class	OfflinePunch
	Offline transient emphasis with a positive boost-dB control. More...

struct	OfflineRegion
	Source-frame interval [begin,end), relative to the start of the source. More...

class	OfflineSoftClipper
	OFFLINE ONLY: calibrates a soft curve to reduce the complete source peak. More...

class	OfflineStereoBalance
	Optional offline balance of an already generated stereo signal. More...

class	OfflineStereoGenerator
	Offline processed-copy stereo generation with a one-width control. More...

class	OfflineTempoAnalyzer
	Complete-source tempo map for automatic offline processors. More...

class	OfflineTransientAnalyzer
	Source-bound attack and pulse maps for offline Dynamics. More...

class	OnsetDetector
	Causal SuperFlux onset detector with lock-free readout. More...

class	Oscillator
	Band-limited oscillator featuring PolyBLEP anti-aliasing and analog-modeled integration. More...

class	Oversampling
	Power-of-two oversampling processor with polyphase anti-aliasing. More...

class	Panner

class	PhaseCorrelation
	Correlation/balance meter and goniometer data source. More...

class	Phaser
	Zero-latency, highly optimized allpass-based phaser. More...

class	Phasor
	Phase accumulator generating a [0, 1) ramp for oscillators and modulation. More...

class	PitchCorrector
	Scale-aware monophonic retune over the framework's YIN detector and phase-vocoder shifter. More...

class	PitchDetector
	Thread-safe YIN pitch detector with lock-free readout. More...

class	PitchFollower
	Gated, octave-safe, semitone-smoothed pitch tracking source. More...

class	PitchShifter
	Real-time phase-vocoder pitch shifter (+-12 semitones, stereo-linked). More...

class	ProcessorChain
	Compile-time chain of audio processors. More...

class	Resampler
	Windowed-sinc sample rate converter optimized for real-time DSP. More...

class	Reverb
	Convolution reverb with IR loading, dry/wet, and pre-delay. More...

class	RingBuffer
	Power-of-two circular buffer with compile-time interpolated read access. More...

class	RingModulator
	Signal x carrier ring modulation with mix control and zero-latency smoothing. More...

class	SampleAndHold
	Holds a sample value for N samples or until externally triggered. More...

class	Sampler
	Polyphonic multi-zone sample player. More...

class	Saturation
	Professional multi-algorithm saturation processor with analog simulation. More...

class	SincInterpolator
	32-tap Kaiser-windowed sinc reader for transparent fractional reads. More...

class	SmoothedValue
	Zero-allocation parameter smoother for real-time audio. More...

class	SpectralDenoiser
	Learn-a-profile spectral noise reduction (hiss/hum/room-tone). More...

class	SpectralFreeze
	Frequency-domain hold with tonal and diffuse phase modes. More...

class	SpectralProcessor
	High-performance STFT analysis-modification-synthesis pipeline. More...

class	SpectrumAnalyzer
	Real-time FFT spectrum analyser with per-bin smoothing and peak hold. More...

class	SpinLock
	A minimal, real-time safe spin lock with a TTAS wait loop. More...

class	SpscQueue

class	StateReader
	Tolerant reader: missing keys yield defaults, unknown keys are skipped. More...

class	StateVariableFilter
	TPT State Variable Filter with simultaneous multi-output. More...

class	StateWriter
	Serializes key/value parameters into a versioned blob. More...

class	StereoGenerator
	A stereo generator that preserves the delayed original mid signal. More...

class	StereoWidth
	High-performance stereo image processor with phase-aligned bass mono. More...

class	StretchedSincReader
	Band-limited fractional reader for read rates from 1 to 4. More...

class	TapeMachine
	Reel-to-reel tape emulation with physical hysteresis and transport. More...

class	TimeStretch
	Real-time and offline time stretching, 0.5x to 2x, pitch unchanged. More...

class	TransformerModel
	Physical audio-transformer coloration (flux-domain JA hysteresis). More...

class	TransientDesigner
	Zero-allocation, thread-safe transient shaper. More...

class	Tremolo
	LFO-driven amplitude modulation with stereo auto-pan option. More...

class	TruePeakDetector
	Per-channel 4x-oversampled inter-sample peak estimator. More...

class	TubePreamp
	One/two 12AX7 stages with sag and a WDF tone circuit. More...

class	Vibrato
	Professional-grade pitch vibrato with LFO FM and parameter smoothing. More...

class	WaveshapeTable
	Zero-latency lookup-table waveshaper with RT-safe gain modulation. More...

class	WavetableOscillator
	Professional mipmapped wavetable oscillator for bandlimited synthesis. More...

class	WavFile
	Complete WAV file reader and writer in pure C++20. More...

struct	WindowFunctions
	Static utility generating window functions for DSP analysis/synthesis. More...

class	ZeroLatencyConvolver
	Gardner-style non-uniform partitioned convolver (zero latency, flat CPU). More...

Concepts
concept	FloatType
	Constrains a type to IEEE floating-point (float or double).

concept	AudioProcessor
	A type that can prepare, process audio blocks, and reset state.

concept	SampleProcessor
	An AudioProcessor that additionally supports scalar per-sample processing.

concept	GeneratorProcessor
	A real-time safe source processor (oscillators, noise, LFOs).

Enumerations
enum class	OfflineSoftClipCurve { Sine , Tanh , GoldenRatio }
	Soft curves shared with Clipper, including its sine approximation. More...

enum class	OfflineStatus : std::uint8_t { Success , NoChange , EmptyInput , InvalidInput , UnsupportedLayout , NonFiniteInput , SourceMismatch , SourceReadFailed , SinkFailed , CallbackFailed , Cancelled , MemoryLimit , AllocationFailure , NumericalFailure , TargetUnreachable }
	Explicit completion or no-publication outcome of an offline job. More...

enum class	OfflinePhase : std::uint8_t { Analyze , Plan , Verify , Render }
	Current kind of work; completed/total restart for each pass, and a phase may recur. More...

enum class	InterpMethod { Linear , Cubic , Hermite , Lagrange }
	Interpolation method for fractional-sample reads. More...

enum class	MidiEventKind : uint8_t { Channel , SysExF0 , SysExF7 , Meta }
	Semantic kind of a Standard MIDI File event. More...

Functions
template<FloatType T>
T	decibelsToGain (T dB, T minusInfinityDb=T(-100)) noexcept
	Converts a value in decibels to linear gain.

template<FloatType T>
T	gainToDecibels (T gain, T minusInfinityDb=T(-100)) noexcept
	Converts a linear gain value to decibels.

template<FloatType T>
T	mapRange (T value, T inMin, T inMax, T outMin, T outMax) noexcept
	Maps a value from one range to another (linear interpolation).

template<FloatType T>
T	moveTowards (T from, T to, T maxDelta) noexcept
	Moves a value toward a target by at most a given distance.

template<FloatType T>
T	fastTanh (T x) noexcept
	Fast tanh approximation using Pade rational function.

template<FloatType T>
T	fastPow10 (T x) noexcept
	Fast approximation of 10^x using exp2.

template<FloatType T>
T	fastExp (T x) noexcept
	Fast approximation of e^x via std::exp2 (~2x faster than std::exp on MSVC).

template<FloatType T>
T	fastTan (T x) noexcept
	Fast approximation of tan(x) using a Pade [5,4] rational approximant.

template<FloatType T>
T	fastSin (T x) noexcept
	Fast sine approximation (degree-9 odd minimax polynomial).

template<FloatType T>
T	fastCos (T x) noexcept
	Fast cosine approximation. See fastSin() for accuracy notes (the pi/2 offset costs float about half an ulp more).

template<FloatType T>
T	fastLog (T x) noexcept
	Fast natural logarithm approximation.

template<FloatType T>
T	wrapPhase (T phase) noexcept
	Normalises a phase value to the range [0, 2*pi).

template<FloatType T>
T	interpolateLinear (T y0, T y1, T frac) noexcept
	Linear interpolation between two adjacent samples.

template<FloatType T>
T	interpolateLinear (const T *buffer, int length, T position) noexcept
	Linear interpolation reading directly from a circular buffer.

template<FloatType T>
T	interpolateHermite (T y0, T y1, T y2, T y3, T frac) noexcept
	4-point, 3rd-order Hermite interpolation (optimized x-form).

template<FloatType T>
T	interpolateHermite (const T *buffer, int length, T position) noexcept

template<FloatType T>
T	interpolateCubic (const T *buffer, int length, T position) noexcept
	Alias of interpolateHermite (Catmull-Rom evaluated in Hermite form). Kept for backward compatibility.

template<FloatType T>
T	interpolateLagrange (T y0, T y1, T y2, T y3, T frac) noexcept
	4-point Lagrange interpolation from discrete samples.

template<FloatType T>
T	interpolateLagrange (const T *buffer, int length, T position) noexcept

template<FloatType T>
T	interpolateAllpass (T currentSample, T previousSample, T frac, T &state) noexcept
	Allpass interpolation (first-order Thiran) for fractional delay.

bool	offlineSucceeded (OfflineStatus status) noexcept
	True for successful processing, including an explicit identity result.

std::string	stateToJson (const std::vector< uint8_t > &blob)
	Renders a state blob as a flat JSON object string.

std::vector< uint8_t >	stateFromJson (const std::string &json)
	Parses the JSON produced by stateToJson() back into a blob.

constexpr uint32_t	stateId (const char(&tag)[5]) noexcept
	Builds a FOURCC processor id, e.g. dspark::stateId("COMP").

Variables
template<FloatType T>
constexpr T	pi = std::numbers::pi_v<T>
	Pi (3.14159...) for the given floating-point type.

template<FloatType T>
constexpr T	twoPi = T(2) * std::numbers::pi_v<T>
	2 * Pi (6.28318...).

template<FloatType T>
constexpr T	invTwoPi = T(1) / twoPi<T>
	1 / (2 * Pi) (0.15915...). Useful for fast phase divisions.

template<FloatType T>
constexpr T	halfPi = std::numbers::pi_v<T> / T(2)
	Pi / 2 (1.57079...). Quarter period; sin/cos phase offset.

template<FloatType T>
constexpr T	sqrt2 = std::numbers::sqrt2_v<T>
	Square root of 2 (1.41421...).

template<FloatType T>
constexpr T	invSqrt2 = T(1) / std::numbers::sqrt2_v<T>
	1 / square root of 2 (0.70710...). Butterworth Q factor.

constexpr std::size_t	kCacheLineSize = 64

Detailed Description

Main namespace for the DSPark framework.

Enumeration Type Documentation

◆ InterpMethod

enum class dspark::InterpMethod

strong

Interpolation method for fractional-sample reads.

Enumerator
Linear	2-point linear (fast, lower quality)
Cubic	4-point Catmull-Rom (good balance)
Hermite	4-point Hermite (smooth transients, best for modulated delay)
Lagrange	4-point Lagrange (highest accuracy, static delay)

Definition at line 46 of file RingBuffer.h.

◆ MidiEventKind

enum class dspark::MidiEventKind : uint8_t

strong

Semantic kind of a Standard MIDI File event.

Enumerator
Channel
SysExF0
SysExF7
Meta

Definition at line 40 of file MidiFile.h.

◆ OfflinePhase

enum class dspark::OfflinePhase : std::uint8_t

strong

Current kind of work; completed/total restart for each pass, and a phase may recur.

Enumerator
Analyze
Plan
Verify
Render

Definition at line 109 of file OfflineProcessing.h.

◆ OfflineSoftClipCurve

enum class dspark::OfflineSoftClipCurve

strong

Soft curves shared with Clipper, including its sine approximation.

Enumerator
Sine
Tanh
GoldenRatio

Definition at line 30 of file OfflineClip.h.

◆ OfflineStatus

enum class dspark::OfflineStatus : std::uint8_t

strong

Explicit completion or no-publication outcome of an offline job.

Enumerator
Success
NoChange
EmptyInput
InvalidInput
UnsupportedLayout
NonFiniteInput
SourceMismatch
SourceReadFailed
SinkFailed
CallbackFailed
Cancelled
MemoryLimit
AllocationFailure
NumericalFailure
TargetUnreachable	Exact protected PCM prevents the requested processing target.

Definition at line 54 of file OfflineProcessing.h.

Function Documentation

◆ decibelsToGain()

template<FloatType T>

T dspark::decibelsToGain	(	T	dB,
		T	minusInfinityDb = `T(-100)`
	)

inlinenoexcept

Converts a value in decibels to linear gain.

Parameters

dB	Value in decibels.
minusInfinityDb	Values at or below this threshold return 0. Default: -100 dB.

Returns: Linear gain (0 for silence, 1 for unity, >1 for boost).

Definition at line 74 of file DspMath.h.

◆ fastCos()

template<FloatType T>

T dspark::fastCos ( T x )

inlinenoexcept

Fast cosine approximation. See fastSin() for accuracy notes (the pi/2 offset costs float about half an ulp more).

Parameters

x	Argument in radians.

Returns: Approximation of cos(x).

Definition at line 276 of file DspMath.h.

◆ fastExp()

template<FloatType T>

T dspark::fastExp ( T x )

inlinenoexcept

Fast approximation of e^x via std::exp2 (~2x faster than std::exp on MSVC).

Uses the identity e^x = 2^(x * log2(e)).

Parameters

x	Exponent. No range clamping is applied.

Returns: Approximation of e^x.

Definition at line 202 of file DspMath.h.

◆ fastLog()

template<FloatType T>

T dspark::fastLog ( T x )

inlinenoexcept

Fast natural logarithm approximation.

Splits the input into exponent and mantissa via std::frexp, then evaluates the classic 4-term atanh series (Cephes style) for ln of the mantissa, centred on [sqrt(0.5), sqrt(2)). Relative error is below 2e-7: ample for envelope/dB work. Roughly 2-4x faster than std::log.

Parameters

x	Input value. Must be > 0 (no guard: matches std::log contract).

Returns: Approximation of ln(x).

Definition at line 293 of file DspMath.h.

◆ fastPow10()

template<FloatType T>

T dspark::fastPow10 ( T x )

inlinenoexcept

Fast approximation of 10^x using exp2.

Uses the identity 10^x = 2^(x * log2(10)). Useful in dB conversions where exact precision is not critical.

Parameters

x Exponent.

Returns: Approximation of 10^x.

Definition at line 183 of file DspMath.h.

◆ fastSin()

template<FloatType T>

T dspark::fastSin ( T x )

inlinenoexcept

Fast sine approximation (degree-9 odd minimax polynomial).

The coefficients are a Remez minimax fit of sin on [-pi/2, pi/2] under the constraint that the polynomial is exactly 1 at pi/2, so the output never overshoots the unit circle in double. Maximum absolute error is ~3.7e-9 in double (about -168 dB) and float-rounding-limited (~1.8e-7, about -135 dB) in float: a pure sine rendered with it is cleaner than a 24-bit converter. About 3-6x faster than std::sin depending on platform. The input is range-reduced internally (two-term Cody-Waite), so any finite argument within a few thousand periods of zero stays accurate.

Parameters

x	Argument in radians.

Returns: Approximation of sin(x).

Definition at line 248 of file DspMath.h.

◆ fastTan()

template<FloatType T>

T dspark::fastTan ( T x )

inlinenoexcept

Fast approximation of tan(x) using a Pade [5,4] rational approximant.

Accurate to better than 0.01% for |x| <= 1.45 and ~0.1% up to the 1.52 fallback limit. Outside that range, falls back to std::tan to avoid the singularities at +-pi/2 producing absurd results.

Useful for the bilinear-transform tan(pi*f/Fs) term: with this accuracy a 20 kHz cutoff at 44.1 kHz lands within a fraction of a cent of the target. Roughly 3x faster than std::tan on MSVC.

Parameters

x	Argument in radians.

Returns: Approximation of tan(x).

Definition at line 222 of file DspMath.h.

◆ fastTanh()

template<FloatType T>

T dspark::fastTanh ( T x )

inlinenoexcept

Fast tanh approximation using Pade rational function.

Approximately 5x faster than std::tanh. Optimized for SIMD without branching. Input is clamped to [-3, 3] maintaining C0 continuity to prevent aliasing. Max output amplitude is ~0.9954.

Note: The clamp at |x| = 3 is C0 but not C1: the derivative has a small discontinuity there (output is already ~0.9954, so the resulting kink is inaudible in practice). Use std::tanh where exact C1 behaviour matters.

Parameters

x	Input value.

Returns: Approximation of tanh(x), smoothly bounded.

Definition at line 161 of file DspMath.h.

◆ gainToDecibels()

template<FloatType T>

T dspark::gainToDecibels	(	T	gain,
		T	minusInfinityDb = `T(-100)`
	)

inlinenoexcept

Converts a linear gain value to decibels.

Parameters

gain	Linear gain (must be >= 0).
minusInfinityDb	Returned for zero or negative gain. Default: -100 dB.

Returns: Value in decibels.

Definition at line 89 of file DspMath.h.

◆ interpolateAllpass()

template<FloatType T>

T dspark::interpolateAllpass	(	T	currentSample,
		T	previousSample,
		T	frac,
		T &	state
	)

inlinenoexcept

Allpass interpolation (first-order Thiran) for fractional delay.

Perfectly flat magnitude response at every frequency, unlike polynomial interpolators (which low-pass); the cost is a frequency-dependent phase response and a recursive state.

Warning: Allpass interpolation is IIR (recursive). Do NOT modulate frac quickly (e.g. audio-rate LFOs): the state carries history filtered with the previous coefficient and produces loud clicks. Best for static or slowly changing delays; use interpolateHermite for modulated delay lines.

The filter is stable for any frac > 0, but as frac approaches 0 the pole approaches z = -1 and the interpolator rings for thousands of samples near Nyquist. Canonical usage keeps the fractional delay in [0.5, 1.5): when the fractional part f of the total delay is below 0.5, read one integer sample earlier and pass frac = f + 1 instead.

Parameters

currentSample	The current input sample (x[n]).
previousSample	The previous input sample (x[n-1]).
frac	Fractional delay in samples, relative to x[n]. Stable for any value > 0; see the [0.5, 1.5) mapping above for clean low-frac behaviour.
state	Allpass filter state (y[n-1]). Maintained by the caller; initialise to 0 and keep one state per delay tap per channel.

Returns: Interpolated sample value (y[n]).

Definition at line 279 of file Interpolation.h.

◆ interpolateCubic()

template<FloatType T>

T dspark::interpolateCubic	(	const T *	buffer,
		int	length,
		T	position
	)

inlinenoexcept

Alias of interpolateHermite (Catmull-Rom evaluated in Hermite form). Kept for backward compatibility.

Definition at line 178 of file Interpolation.h.

◆ interpolateHermite() [1/2]

template<FloatType T>

T dspark::interpolateHermite	(	const T *	buffer,
		int	length,
		T	position
	)

inlinenoexcept

Definition at line 151 of file Interpolation.h.

◆ interpolateHermite() [2/2]

template<FloatType T>

T dspark::interpolateHermite	(	T	y0,
		T	y1,
		T	y2,
		T	y3,
		T	frac
	)

inlinenoexcept

4-point, 3rd-order Hermite interpolation (optimized x-form).

Mathematically identical to Catmull-Rom but evaluated with fewer multiplications than the standard polynomial form.

Parameters

y0	Sample at index n-1.
y1	Sample at index n.
y2	Sample at index n+1.
y3	Sample at index n+2.
frac	Fractional position between y1 and y2 (0.0 to 1.0).

Returns: Interpolated sample.

Definition at line 126 of file Interpolation.h.

◆ interpolateLagrange() [1/2]

template<FloatType T>

T dspark::interpolateLagrange	(	const T *	buffer,
		int	length,
		T	position
	)

inlinenoexcept

Definition at line 230 of file Interpolation.h.

◆ interpolateLagrange() [2/2]

template<FloatType T>

T dspark::interpolateLagrange	(	T	y0,
		T	y1,
		T	y2,
		T	y3,
		T	frac
	)

inlinenoexcept

4-point Lagrange interpolation from discrete samples.

Reconstructs polynomials up to degree 3 exactly (the divisions of the Lagrange basis are precomputed constants).

Parameters

y0	Sample at index n-1.
y1	Sample at index n.
y2	Sample at index n+1.
y3	Sample at index n+2.
frac	Fractional position between y1 and y2 (0.0 to 1.0).

Returns: Interpolated sample.

Definition at line 196 of file Interpolation.h.

◆ interpolateLinear() [1/2]

template<FloatType T>

T dspark::interpolateLinear	(	const T *	buffer,
		int	length,
		T	position
	)

inlinenoexcept

Linear interpolation reading directly from a circular buffer.

The buffer is treated as circular: reading at position length - 0.5 interpolates between the last and the first sample.

Parameters

buffer	Pointer to the start of the audio buffer.
length	Size of the buffer in samples (must be > 0).
position	Absolute read position.

Returns: Interpolated sample.

Precondition: 0 <= position < length. Violations assert in debug builds; release builds clamp to the nearest valid sample (NaN reads position 0).

Definition at line 91 of file Interpolation.h.

◆ interpolateLinear() [2/2]

template<FloatType T>

T dspark::interpolateLinear	(	T	y0,
		T	y1,
		T	frac
	)

inlinenoexcept

Linear interpolation between two adjacent samples.

Parameters

y0	Sample at index n.
y1	Sample at index n+1.
frac	Fractional position (0.0 to 1.0).

Returns: Interpolated sample.

Definition at line 72 of file Interpolation.h.

◆ mapRange()

template<FloatType T>

T dspark::mapRange	(	T	value,
		T	inMin,
		T	inMax,
		T	outMin,
		T	outMax
	)

inlinenoexcept

Maps a value from one range to another (linear interpolation).

Includes a safety check to prevent division by zero if inMin == inMax.

Parameters

value	The input value to remap.
inMin	Lower bound of the input range.
inMax	Upper bound of the input range.
outMin	Lower bound of the output range.
outMax	Upper bound of the output range.

Returns: Remapped value. Returns outMin if input bounds are identical.

Definition at line 114 of file DspMath.h.

◆ moveTowards()

template<FloatType T>

T dspark::moveTowards	(	T	from,
		T	to,
		T	maxDelta
	)

inlinenoexcept

Moves a value toward a target by at most a given distance.

The rate-limiter step: lands exactly on the target once within reach. Evaluated with maxDelta = step * (i + 1) it gives the i-th sample of a rate-limited ramp in closed form (no loop-carried state), which is how the framework's dry/wet ramps keep a minimum duration whatever the block size.

Parameters

from	Current value.
to	Target value.
maxDelta	Largest allowed move (non-negative).

Returns: to when |to - from| <= maxDelta, else from moved by maxDelta toward to.

Definition at line 134 of file DspMath.h.

◆ offlineSucceeded()

bool dspark::offlineSucceeded ( OfflineStatus status )

inlinenoexcept

True for successful processing, including an explicit identity result.

Definition at line 74 of file OfflineProcessing.h.

◆ stateFromJson()

std::vector< uint8_t > dspark::stateFromJson ( const std::string & json )

inline

Parses the JSON produced by stateToJson() back into a blob.

Accepts exactly that flat subset (id/version/params of numbers and bools); returns an empty vector on malformed input. Number-typed params re-enter as floats; integer-coded modes survive because setState() readers request the type they stored, and stateToJson tags ints without decimals – both int and float lookups are attempted by the float/int read pair below.

Definition at line 645 of file StateBlob.h.

◆ stateId()

constexpr uint32_t dspark::stateId ( const char(&) tag[5] )

constexprnoexcept

Builds a FOURCC processor id, e.g. dspark::stateId("COMP").

Definition at line 651 of file StateBlob.h.

◆ stateToJson()

std::string dspark::stateToJson ( const std::vector< uint8_t > & blob )

inline

Renders a state blob as a flat JSON object string.

Definition at line 631 of file StateBlob.h.

◆ wrapPhase()

template<FloatType T>

T dspark::wrapPhase ( T phase )

inlinenoexcept

Normalises a phase value to the range [0, 2*pi).

Optimized for hot paths: avoids std::fmod (slow, hostile to vectorisation) in favour of inverse multiplication and flooring.

Parameters

phase Phase in radians.

Returns: Phase wrapped safely to [0, 2*pi).

Definition at line 326 of file DspMath.h.

Variable Documentation

◆ halfPi

template<FloatType T>

constexpr T dspark::halfPi = std::numbers::pi_v<T> / T(2)

inlineconstexpr

Pi / 2 (1.57079...). Quarter period; sin/cos phase offset.

Definition at line 54 of file DspMath.h.

◆ invSqrt2

template<FloatType T>

constexpr T dspark::invSqrt2 = T(1) / std::numbers::sqrt2_v<T>

inlineconstexpr

1 / square root of 2 (0.70710...). Butterworth Q factor.

Definition at line 60 of file DspMath.h.

◆ invTwoPi

template<FloatType T>

constexpr T dspark::invTwoPi = T(1) / twoPi<T>

inlineconstexpr

1 / (2 * Pi) (0.15915...). Useful for fast phase divisions.

Definition at line 51 of file DspMath.h.

◆ kCacheLineSize

constexpr std::size_t dspark::kCacheLineSize = 64

inlineconstexpr

Definition at line 62 of file SpscQueue.h.

◆ pi

template<FloatType T>

constexpr T dspark::pi = std::numbers::pi_v<T>

inlineconstexpr

Pi (3.14159...) for the given floating-point type.

Definition at line 45 of file DspMath.h.

◆ sqrt2

template<FloatType T>

constexpr T dspark::sqrt2 = std::numbers::sqrt2_v<T>

inlineconstexpr

Square root of 2 (1.41421...).

Definition at line 57 of file DspMath.h.

◆ twoPi

template<FloatType T>

constexpr T dspark::twoPi = T(2) * std::numbers::pi_v<T>

inlineconstexpr

2 * Pi (6.28318...).

Definition at line 48 of file DspMath.h.

Namespaces

Classes

Concepts

Enumerations

Functions

Variables

Detailed Description

Enumeration Type Documentation

◆ InterpMethod

◆ MidiEventKind

◆ OfflinePhase

◆ OfflineSoftClipCurve

◆ OfflineStatus

Function Documentation

◆ decibelsToGain()

◆ fastCos()

◆ fastExp()

◆ fastLog()

◆ fastPow10()

◆ fastSin()

◆ fastTan()

◆ fastTanh()

◆ gainToDecibels()

◆ interpolateAllpass()

◆ interpolateCubic()

◆ interpolateHermite() [1/2]

◆ interpolateHermite() [2/2]

◆ interpolateLagrange() [1/2]

◆ interpolateLagrange() [2/2]

◆ interpolateLinear() [1/2]

◆ interpolateLinear() [2/2]

◆ mapRange()

◆ moveTowards()

◆ offlineSucceeded()

◆ stateFromJson()

◆ stateId()

◆ stateToJson()

◆ wrapPhase()

Variable Documentation

◆ halfPi

◆ invSqrt2

◆ invTwoPi

◆ kCacheLineSize

◆ pi

◆ sqrt2

◆ twoPi