webaudio.lib

This library implement WebAudio filters, using their C++ version as a starting point, taken from Mozilla Firefox implementation.


(wa.)lowpass2

Standard second-order resonant lowpass filter with 12dB/octave rolloff. Frequencies below the cutoff pass through, frequencies above it are attenuated.

Usage

_: lowpass2(f0, Q, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • Q: the quality factor
  • dtune: detuning of the frequency in cents

Reference


(wa.)highpass2

Standard second-order resonant highpass filter with 12dB/octave rolloff. Frequencies below the cutoff are attenuated, frequencies above it pass through.

Usage

_: highpass2(f0, Q, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • Q: the quality factor
  • dtune: detuning of the frequency in cents

Reference


(wa.)bandpass2

Standard second-order bandpass filter. Frequencies outside the given range of frequencies are attenuated, the frequencies inside it pass through.

Usage

_: bandpass2(f0, Q, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • Q: the quality factor
  • dtune: detuning of the frequency in cents

Reference


(wa.)notch2

Standard notch filter, also called a band-stop or band-rejection filter. It is the opposite of a bandpass filter: frequencies outside the give range of frequencies pass through, frequencies inside it are attenuated.

Usage

_: notch2(f0, Q, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • Q: the quality factor
  • dtune: detuning of the frequency in cents

Reference


(wa.)allpass2

Standard second-order allpass filter. It lets all frequencies through, but changes the phase-relationship between the various frequencies.

Usage

_: allpass2(f0, Q, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • Q: the quality factor
  • dtune: detuning of the frequency in cents

Reference


(wa.)peaking2

Frequencies inside the range get a boost or an attenuation, frequencies outside it are unchanged.

Usage

_: peaking2(f0, gain, Q, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • gain: the gain in dB
  • Q: the quality factor
  • dtune: detuning of the frequency in cents

Reference


(wa.)lowshelf2

Standard second-order lowshelf filter. Frequencies lower than the frequency get a boost, or an attenuation, frequencies over it are unchanged.

_: lowshelf2(f0, gain, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • gain: the gain in dB
  • dtune: detuning of the frequency in cents

Reference


(wa.)highshelf2

Standard second-order highshelf filter. Frequencies higher than the frequency get a boost or an attenuation, frequencies lower than it are unchanged.

_: highshelf2(f0, gain, dtune) :_

Where:

  • f0: cutoff frequency in Hz
  • gain: the gain in dB
  • dtune: detuning of the frequency in cents

Reference