cutcutcodec.core.filter.audio.resample.FilterAudioAntiAliasing

class cutcutcodec.core.filter.audio.resample.FilterAudioAntiAliasing(in_streams: Iterable[StreamAudio], cutoff: Real)[source]

Anti-aliasing filter for audio subsampling.

This filter is a class 1 finite impulse response linear phase low-pass filter.

Attributes

cutofffloat: The cutoff frequency in Hz (readonly).
delayFraction: The delay introduced by the filter in seconds (readonly).

Examples

>>> from cutcutcodec.core.filter.audio.resample import FilterAudioAntiAliasing
>>> from cutcutcodec.core.generation.audio.equation import GeneratorAudioEquation
>>> (audio_a4,) = GeneratorAudioEquation("sin(2*pi*440*t)").out_streams
>>> (audio_a5,) = GeneratorAudioEquation("sin(2*pi*880*t)").out_streams
>>> out_a4, out_a5 = FilterAudioAntiAliasing([audio_a4, audio_a5], 622).out_streams
>>> (out_a4.snapshot(10, 48000, 768000)**2).mean()  # signal power (no attenuation)
tensor(0.5000)
>>> (out_a5.snapshot(10, 48000, 768000)**2).mean()  # signal power (attenuation)
tensor(3.9965e-08)
>>>

Initialise and create the class.

Parameters

in_streamstyping.Iterable[Stream]: Transmitted to cutcutcodec.core.filter.audio.fir.FilterAudioFIR.
cutofffloat: The cut-off frequency in Hz. For the Shannon criteria, it is the half sample rate. The margin, the band with and the attenuation have been automatically chosen for the earing sensibility in the case of an audio application.

property cutoff: Fraction: Return the cutoff frequency in Hz.

classmethod default()[source]: Provide a minimalist example of an instance of this node.

property delay: Fraction: Return the delay introduced by the filter in seconds.

resample_fir(rate: int) → Tensor[source]: Recompute the antialiasing fir from scratch.