VoxaTrace/com.musicmuni.voxatrace.calibra/CalibraPitch/Detector

Detector

Realtime pitch detector for processing audio buffers.

Handles variable buffer sizes by internally accumulating samples until it has enough for pitch detection. This is important because:

iOS delivers audio at hardware sample rate (48kHz) in ~100ms chunks
After resampling to 16kHz, buffers may be smaller than required frame size

Implementations:

YinRealtimeDetector: YIN algorithm - frame-by-frame DSP, no ML dependency
SwiftF0RealtimeDetector: SwiftF0 neural network - batch-oriented, higher accuracy

Constructors

Detector

constructor()

Properties

config

abstract val config: PitchDetectorConfig

The configuration used to create this detector

hasProcessing

abstract val hasProcessing: Boolean

Check if post-processing is active

latencyMs

abstract val latencyMs: Float

Detection latency in milliseconds.

livePitchContour

abstract val livePitchContour: StateFlow<PitchContour>

Live pitch contour accumulated during recording.

processingEnabled

abstract var processingEnabled: Boolean

Whether post-processing is currently enabled. Set to enable/disable at runtime.

Functions

clearPitchContour

abstract fun clearPitchContour()

Clear the accumulated pitch contour.

open override fun close()

AutoCloseable implementation - delegates to release()

detect

@ShouldRefineInSwift

abstract fun detect(samples: FloatArray, sampleRate: Int): PitchPoint

Detect pitch from audio samples.

duplicate

abstract fun duplicate(): CalibraPitch.Detector

Create a duplicate detector with the same configuration.

getAmplitude

@ShouldRefineInSwift

abstract fun getAmplitude(samples: FloatArray, sampleRate: Int): Float

Get the amplitude (RMS) of the audio samples.

release

abstract fun release()

Release all resources. Must be called when done.

reset

abstract fun reset()

Reset state and internal buffer. Call when starting a new audio stream.

setContourMaxDuration

abstract fun setContourMaxDuration(seconds: Float)

Set the maximum duration for the live pitch contour.