LowPassFilterWorklet

AudioFilterWorklet → ceramic.LowPassFilterWorklet (Class)

The audio processing worklet for the low-pass filter. Implements a second-order biquad low-pass filter with per-channel processing.

Instance Members

process(buffer: AudioFilterBuffer, samples: Int, channels: Int, sampleRate: Float, time: Float): Void

Process audio buffer in place. Override this method to implement custom filtering. CAUTION: this may be called from a background thread

Name	Type	Description
`buffer`	AudioFilterBuffer	The audio buffer to process (modify in place, planar layout: one channel after another, not interleaved)
`samples`	Int	Number of samples per channel
`channels`	Int	Number of audio channels (1 = mono, 2 = stereo)
`sampleRate`	Float	Sample rate in Hz
`time`	Float	Current playback time in seconds

new(filterId: Int, bus: Int): Void

Name	Type
`filterId`	Int
`bus`	Int

cutoffFrequency: Float

Cutoff frequency in Hz. Frequencies above this value will be attenuated. Range: 1 Hz to half the sample rate (Nyquist frequency). Default: 1000 Hz

gain: Float

Filter gain/amplitude multiplier. Adjusts the overall output level after filtering. Range: 0.0 to any positive value (1.0 = unity gain). Default: 1.0

resonance: Float

Filter resonance/Q factor. Controls the sharpness of the filter and frequency emphasis at the cutoff.

0.707: No resonance (Butterworth response, flat passband)
< 0.707: Gentler rolloff
> 0.707: Sharper rolloff with peak at cutoff
High values (5-30): Creates strong resonant peak (self-oscillation) Range: 0.1 to 30.0 (higher values = more resonance) Default: 0.707

x1: Array<Float>

x2: Array<Float>

y1: Array<Float>

y2: Array<Float>

a0: Float

a1: Float

a2: Float

b1: Float

b2: Float

lastCutoff: Float

lastQ: Float

lastSampleRate: Float

calculateCoefficients(cutoff: Float, q: Float, sampleRate: Float): Void

Calculates biquad filter coefficients for the low-pass response. Uses the standard audio EQ cookbook formulas for a second-order low-pass filter.