You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
207 lines
6.5 KiB
207 lines
6.5 KiB
/* Stereo Phaser/Vibrato effect for Teensy Audio library
|
|
*
|
|
* Author: Piotr Zapart
|
|
* www.hexefx.com
|
|
*
|
|
* Copyright (c) 2021 by Piotr Zapart
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in all
|
|
* copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
* SOFTWARE.
|
|
*/
|
|
|
|
#ifndef _EFFECT_PHASERSTEREO_F32_H
|
|
#define _EFFECT_PHASERSTEREO_F32_H
|
|
|
|
#include <Arduino.h>
|
|
#include "Audio.h"
|
|
#include "AudioStream.h"
|
|
#include "AudioStream_F32.h"
|
|
#include "arm_math.h"
|
|
|
|
#define PHASER_STEREO_STAGES 12
|
|
|
|
class AudioEffectPhaserStereo_F32 : public AudioStream_F32
|
|
{
|
|
public:
|
|
AudioEffectPhaserStereo_F32();
|
|
~AudioEffectPhaserStereo_F32();
|
|
virtual void update();
|
|
|
|
/**
|
|
* @brief Scale and offset the modulation signal. It can be the internal LFO
|
|
* or the incomig routed modulation AudioSignal.
|
|
* LFO will oscillate between these two max and min values.
|
|
*
|
|
* @param top top level of the LFO
|
|
* @param bottom bottom level of the LFO
|
|
*/
|
|
void depth(float32_t top, float32_t bottom)
|
|
{
|
|
float32_t a, b;
|
|
lfo_top = constrain(top, 0.0f, 1.0f);
|
|
lfo_btm = constrain(bottom, 0.0f, 1.0f);
|
|
|
|
a = abs(lfo_top - lfo_btm); // scaler
|
|
b = min(lfo_top, lfo_btm); // bias
|
|
__disable_irq();
|
|
lfo_bias = b;
|
|
lfo_scaler = a;
|
|
__enable_irq();
|
|
}
|
|
/**
|
|
* @brief classic way of setting the depth: LFO centered around 0.5
|
|
*
|
|
* @param dpth modulation wave amplitude
|
|
*/
|
|
void depth(float32_t value)
|
|
{
|
|
value = constrain(value, 0.0f, 1.0f);
|
|
value *= 0.5f;
|
|
lfo_top = 0.5f + value;
|
|
lfo_btm = 0.5f - value;
|
|
__disable_irq();
|
|
lfo_bias = 0.5f;
|
|
lfo_scaler = value;
|
|
__enable_irq();
|
|
}
|
|
void top(float32_t value)
|
|
{
|
|
lfo_top = constrain(value, 0.0f, 1.0f);
|
|
depth(lfo_top, lfo_btm);
|
|
}
|
|
void btm(float32_t value)
|
|
{
|
|
lfo_btm = constrain(value, 0.0f, 1.0f);
|
|
depth(lfo_top, lfo_btm);
|
|
}
|
|
/**
|
|
* @brief Controls the internal LFO, or if a control signal is used, scales it
|
|
* Use this function to update all lfo parameteres at once
|
|
*
|
|
* @param f_Hz lfo frequency, use 0.0f for manual phaser control
|
|
* @param phase phase shift between the LFOs L and R waveforms, 0.0-1.0 range
|
|
* @param top lfo top level
|
|
* @param btm lfo bottm level
|
|
*/
|
|
void lfo(float32_t f_Hz, float32_t phase, float32_t top, float32_t btm)
|
|
{
|
|
float32_t a, b, c;
|
|
uint32_t add;
|
|
uint8_t bs;
|
|
|
|
a = constrain(top, 0.0f, 1.0f);
|
|
b = constrain(btm, 0.0f, 1.0f);
|
|
c = abs(a - b); // scaler
|
|
a = min(a, b); // bias
|
|
f_Hz = constrain(f_Hz, 0.0f, AUDIO_SAMPLE_RATE_EXACT/2);
|
|
phase = constrain(phase, 0.0f, 1.0f);
|
|
add = f_Hz * (4294967296.0f / AUDIO_SAMPLE_RATE_EXACT);
|
|
bs = (uint8_t)(phase * 128.0f);
|
|
__disable_irq();
|
|
lfo_scaler = c;
|
|
lfo_bias = a;
|
|
lfo_add = add;
|
|
lfo_lroffset = bs;
|
|
__enable_irq();
|
|
}
|
|
void stereo(float32_t phase)
|
|
{
|
|
uint8_t bs;
|
|
phase = constrain(phase, 0.0f, 1.0f);
|
|
bs = (uint8_t)(phase * 128.0f);
|
|
__disable_irq();
|
|
lfo_lroffset = bs;
|
|
__enable_irq();
|
|
}
|
|
|
|
/**
|
|
* @brief Set the rate of the internal LFO
|
|
*
|
|
* @param f_Hz lfo frequency, use 0.0f for manual phaser control
|
|
*/
|
|
void lfo_rate(float32_t f_Hz)
|
|
{
|
|
float32_t c;
|
|
uint32_t add;
|
|
c = constrain(f_Hz, 0.0f, AUDIO_SAMPLE_RATE_EXACT/2);
|
|
add = c * (4294967296.0 / AUDIO_SAMPLE_RATE_EXACT);
|
|
__disable_irq();
|
|
lfo_add = add;
|
|
__enable_irq();
|
|
}
|
|
/**
|
|
* @brief Controls the feedback parameter
|
|
*
|
|
* @param fdb ffedback value in range 0.0f to 1.0f
|
|
*/
|
|
void feedback(float32_t fdb)
|
|
{
|
|
feedb = constrain(fdb, -1.0f, 1.0f);
|
|
}
|
|
/**
|
|
* @brief Dry / Wet mixer ratio. Classic Phaser sound uses 0.5f for 50% dry and 50%Wet
|
|
* 1.0f will produce 100% wet signal craeting a vibrato effect
|
|
*
|
|
* @param ratio mixing ratio, range 0.0f (full dry) to 1.0f (full wet)
|
|
*/
|
|
void mix(float32_t ratio)
|
|
{
|
|
mix_ratio = constrain(ratio, 0.0f, 1.0f);
|
|
}
|
|
/**
|
|
* @brief Sets the number of stages used in the phaser
|
|
* Allowed values are: 2, 4, 6, 8, 10, 12
|
|
*
|
|
* @param st number of stages, even value <= 12
|
|
*/
|
|
void stages(uint8_t st)
|
|
{
|
|
if (st && st == ((st >> 1) << 1) && st <= PHASER_STEREO_STAGES) // only 2, 4, 6, 8, 12 allowed
|
|
{
|
|
stg = st;
|
|
}
|
|
}
|
|
/**
|
|
* @brief Use to bypass the effect (true)
|
|
*
|
|
* @param state true = bypass on, false = phaser on
|
|
*/
|
|
void bypass_set(bool state) {bps = state;}
|
|
bool bypass_tgl(void) {bps ^= 1; return bps;}
|
|
|
|
private:
|
|
uint8_t stg; // number of stages
|
|
bool bps; // bypass
|
|
audio_block_f32_t *inputQueueArray_f32[3];
|
|
float32_t allpass_x[2][PHASER_STEREO_STAGES]; // allpass inputs
|
|
float32_t allpass_y[2][PHASER_STEREO_STAGES]; // allpass outputs
|
|
float32_t mix_ratio; // 0 = dry. 1.0 = wet
|
|
float32_t feedb; // feedback
|
|
float32_t last_sampleL;
|
|
float32_t last_sampleR;
|
|
uint32_t lfo_phase_acc; // interfnal lfo
|
|
uint32_t lfo_add;
|
|
float32_t lfo_lrphase;
|
|
uint32_t lfo_lroffset;
|
|
float32_t lfo_scaler;
|
|
float32_t lfo_bias;
|
|
float32_t lfo_top;
|
|
float32_t lfo_btm;
|
|
};
|
|
|
|
#endif // _EFFECT_PHASER_H
|
|
|