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Weird Constructor 2021-07-13 03:54:29 +02:00
parent 2112f8bdaf
commit f121f1d3fa
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src/dsp/helpers.rs
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@ -708,6 +708,14 @@ impl Comb {
// one pole lp from valley rack free:
// https://github.com/ValleyAudio/ValleyRackFree/blob/v1.0/src/Common/DSP/OnePoleFilters.cpp
#[inline]
/// Process a very simple one pole 6dB low pass filter.
/// Useful in various applications, from usage in a synthesizer to
/// damping stuff in a reverb/delay.
///
/// * `input` - Input sample
/// * `freq` - Frequency between 1.0 and 22000.0Hz
/// * `israte` - 1.0 / samplerate
/// * `z` - The internal one sample buffer of the filter.
pub fn process_1pole_lowpass(input: f64, freq: f64, israte: f64, z: &mut f64) -> f64 {
let b = (-std::f64::consts::TAU * freq * israte).exp();
let a = 1.0 - b;
@ -718,6 +726,13 @@ pub fn process_1pole_lowpass(input: f64, freq: f64, israte: f64, z: &mut f64) ->
// one pole hp from valley rack free:
// https://github.com/ValleyAudio/ValleyRackFree/blob/v1.0/src/Common/DSP/OnePoleFilters.cpp
#[inline]
/// Process a very simple one pole 6dB high pass filter.
/// Useful in various applications.
///
/// * `input` - Input sample
/// * `freq` - Frequency between 1.0 and 22000.0Hz
/// * `israte` - 1.0 / samplerate
/// * `z` - The internal one sample buffer of the filter.
pub fn process_1pole_highpass(input: f64, freq: f64, israte: f64, z: &mut f64, y: &mut f64) -> f64 {
let b = (-std::f64::consts::TAU * freq * israte).exp();
let a = (1.0 + b) / 2.0;
@ -735,6 +750,14 @@ pub fn process_1pole_highpass(input: f64, freq: f64, israte: f64, z: &mut f64, y
// http://www.willpirkle.com/Downloads/AN-4VirtualAnalogFilters.pdf
// (page 5)
#[inline]
/// Process a very simple one pole 6dB low pass filter in TPT form.
/// Useful in various applications, from usage in a synthesizer to
/// damping stuff in a reverb/delay.
///
/// * `input` - Input sample
/// * `freq` - Frequency between 1.0 and 22000.0Hz
/// * `israte` - 1.0 / samplerate
/// * `z` - The internal one sample buffer of the filter.
pub fn process_1pole_tpt_lowpass(input: f64, freq: f64, israte: f64, z: &mut f64) -> f64 {
let g = (std::f64::consts::PI * freq * israte).tan();
let a = g / (1.0 + g);
@ -752,6 +775,13 @@ pub fn process_1pole_tpt_lowpass(input: f64, freq: f64, israte: f64, z: &mut f64
// http://www.willpirkle.com/Downloads/AN-4VirtualAnalogFilters.pdf
// (page 5)
#[inline]
/// Process a very simple one pole 6dB high pass filter in TPT form.
/// Useful in various applications.
///
/// * `input` - Input sample
/// * `freq` - Frequency between 1.0 and 22000.0Hz
/// * `israte` - 1.0 / samplerate
/// * `z` - The internal one sample buffer of the filter.
pub fn process_1pole_tpt_highpass(input: f64, freq: f64, israte: f64, z: &mut f64) -> f64 {
let g = (std::f64::consts::PI * freq * israte).tan();
let a1 = g / (1.0 + g);