diff --git a/synth_UniformWhiteNoise_F32.cpp b/synth_UniformWhiteNoise_F32.cpp new file mode 100644 index 0000000..0b7cb20 --- /dev/null +++ b/synth_UniformWhiteNoise_F32.cpp @@ -0,0 +1,66 @@ +/* synth_UniformWhiteNoise_F32.cpp + + License: MIT License. Use at your own risk. +*/ + +/* Audio Library for Teensy 3.X + * Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com + * + * Development of this audio library was funded by PJRC.COM, LLC by sales of + * Teensy and Audio Adaptor boards. Please support PJRC's efforts to develop + * open source software by purchasing Teensy or other PJRC products. + * + * 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, development funding 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. + */ + +#include "synth_UniformWhiteNoise_F32.h" +#define I32_TO_F32_NORM_FACTOR (2.3283064E-10) +#define Q31_TO_F32_NORM_FACTOR (4.6566129E-10) + +void AudioSynthUniformWhiteNoise_F32::update(void) + { + audio_block_f32_t *block_f32; + float32_t *pf; + +#if !defined(__ARM_ARCH_7EM__) + return] +#else + if (level < 0.000001f) + return; // special case, turn off update() if level==0. + + block_f32 = AudioStream_F32::allocate_f32(); + if (!block_f32) + return; + pf = block_f32->data; + for(int i=0; ilength; i++) + { + uint64_t x = rnState; + x ^= x >> 12; + x ^= x << 25; + x ^= x >> 27; + rnState = x; + *pf++ = level*((Q31_TO_F32_NORM_FACTOR * (float32_t)((x * UINT64_C(2685821657736338717)) >> 32)) - 1.0f); + } + + AudioStream_F32::transmit(block_f32); + AudioStream_F32::release(block_f32); +#endif + } + + diff --git a/synth_UniformWhiteNoise_F32.h b/synth_UniformWhiteNoise_F32.h new file mode 100644 index 0000000..fa64d9f --- /dev/null +++ b/synth_UniformWhiteNoise_F32.h @@ -0,0 +1,80 @@ +/* synth_UniformWhiteNoise_F32.h --- New July 2025 + Generates a block of uniformly distributed, uncorrelated, white + noise of a range of (-level, +level) as set by amplitude(level) + with a default value of level = 0.0. This replaces the class + synth_whitenoise_F32 and corrects the need for I16 memory as well + providing output that uses the full F32 mantissa of 24-bits. + + Method is xor shift 64 credited to George Marsaglia. See + https://en.wikipedia.org/wiki/Xorshift and + https://forum.pjrc.com/index.php?threads/teensy-4-1-random-number-generator.61125 + post 13 by #Nominal Animal. + Bob Larkin July 2025. Thanks #grrrr + + Derived from synth_whitenoise_F32 that was + extended by: Chip Audette, OpenAudio, Feb 2017 + + License: MIT License. Use at your own risk. +*/ +/* Audio Library for Teensy 3.X + * Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com + * + * Development of this audio library was funded by PJRC.COM, LLC by sales of + * Teensy and Audio Adaptor boards. Please support PJRC's efforts to develop + * open source software by purchasing Teensy or other PJRC products. + * + * 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, development funding 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. + */ + +// ** This does not support Teensy LC (KINETISL). Teensy 3.x and 4.x OK. ** +// Execution time 15 uSec for 128 size block on T4.x. 12 of these are +// the conversionfrom uint32_t to F32 with offset for DC=0. + +#ifndef synth_uniform_white_noise_f32_h_ +#define synth_uniform_white_noise_f32_h_ +#include "Arduino.h" +#include "AudioStream_F32.h" +#include "utility/dspinst.h" + +class AudioSynthUniformWhiteNoise_F32 : public AudioStream_F32 +{ +//GUI: inputs:0, outputs:1 //this line used for automatic generation of GUI node +//GUI: shortName:uniformwhitenoise //this line used for automatic generation of GUI node +public: + AudioSynthUniformWhiteNoise_F32() : AudioStream_F32(0, NULL) { setDefaultValues(); } + AudioSynthUniformWhiteNoise_F32(const AudioSettings_F32 &settings) : + AudioStream_F32(0, NULL) { setDefaultValues(); } + void setDefaultValues(void) { + level = 0.0f; + rnState = 1ULL + instance_count++; + } + + void amplitude(float nL) { + if (nL < 0.0) nL = 0.0; + level = nL; + } + + virtual void update(void); + +private: + float32_t level = 0.0f; + uint64_t rnState; + uint64_t instance_count=0ULL; +}; +#endif