mirror of
https://github.com/InfiniTimeOrg/InfiniTime.git
synced 2024-11-26 23:34:59 +03:00
arduinofft: Move to submodule, define srqt_internal externally
This commit is contained in:
parent
473a0795d6
commit
505520d83b
3
.gitmodules
vendored
3
.gitmodules
vendored
@ -7,3 +7,6 @@
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[submodule "src/libs/QCBOR"]
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path = src/libs/QCBOR
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url = https://github.com/laurencelundblade/QCBOR.git
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[submodule "src/libs/arduinoFFT"]
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path = src/libs/arduinoFFT
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url = https://github.com/kosme/arduinoFFT.git
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@ -672,9 +672,9 @@ set(INCLUDE_FILES
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heartratetask/HeartRateTask.h
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components/heartrate/Ppg.h
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components/heartrate/HeartRateController.h
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libs/arduinoFFT-develop/src/arduinoFFT.h
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libs/arduinoFFT-develop/src/defs.h
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libs/arduinoFFT-develop/src/types.h
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libs/arduinoFFT/src/arduinoFFT.h
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libs/arduinoFFT/src/defs.h
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libs/arduinoFFT/src/types.h
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components/motor/MotorController.h
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buttonhandler/ButtonHandler.h
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touchhandler/TouchHandler.h
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@ -5,8 +5,9 @@
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#include <cstdint>
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// Note: Change internal define 'sqrt_internal sqrt' to
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// 'sqrt_internal sqrtf' to save ~3KB of flash.
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#define sqrt_internal sqrtf
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#define FFT_SPEED_OVER_PRECISION
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#include "libs/arduinoFFT-develop/src/arduinoFFT.h"
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#include "libs/arduinoFFT/src/arduinoFFT.h"
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namespace Pinetime {
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namespace Controllers {
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1
src/libs/arduinoFFT
Submodule
1
src/libs/arduinoFFT
Submodule
@ -0,0 +1 @@
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Subproject commit 419d7b044e56b87de8efbcf76f09c04759628fb4
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3
src/libs/arduinoFFT-develop/.gitignore
vendored
3
src/libs/arduinoFFT-develop/.gitignore
vendored
@ -1,3 +0,0 @@
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/.project
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/sync.ffs_db
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*.*bak
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@ -1,119 +0,0 @@
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/*
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Example of use of the FFT libray
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Copyright (C) 2014 Enrique Condes
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Copyright (C) 2020 Bim Overbohm (header-only, template, speed improvements)
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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In this example, the Arduino simulates the sampling of a sinusoidal 1000 Hz
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signal with an amplitude of 100, sampled at 5000 Hz. Samples are stored
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inside the vReal array. The samples are windowed according to Hamming
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function. The FFT is computed using the windowed samples. Then the magnitudes
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of each of the frequencies that compose the signal are calculated. Finally,
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the frequency with the highest peak is obtained, being that the main frequency
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present in the signal.
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*/
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#include "arduinoFFT.h"
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/*
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These values can be changed in order to evaluate the functions
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*/
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const uint16_t samples = 64; //This value MUST ALWAYS be a power of 2
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const double signalFrequency = 1000;
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const double samplingFrequency = 5000;
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const uint8_t amplitude = 100;
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/*
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These are the input and output vectors
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Input vectors receive computed results from FFT
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*/
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double vReal[samples];
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double vImag[samples];
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/* Create FFT object */
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ArduinoFFT<double> FFT = ArduinoFFT<double>(vReal, vImag, samples, samplingFrequency);
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#define SCL_INDEX 0x00
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#define SCL_TIME 0x01
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#define SCL_FREQUENCY 0x02
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#define SCL_PLOT 0x03
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void setup()
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{
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Serial.begin(115200);
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Serial.println("Ready");
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}
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void loop()
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{
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/* Build raw data */
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double cycles = (((samples-1) * signalFrequency) / samplingFrequency); //Number of signal cycles that the sampling will read
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for (uint16_t i = 0; i < samples; i++)
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{
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vReal[i] = int8_t((amplitude * (sin((i * (TWO_PI * cycles)) / samples))) / 2.0);/* Build data with positive and negative values*/
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//vReal[i] = uint8_t((amplitude * (sin((i * (twoPi * cycles)) / samples) + 1.0)) / 2.0);/* Build data displaced on the Y axis to include only positive values*/
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vImag[i] = 0.0; //Imaginary part must be zeroed in case of looping to avoid wrong calculations and overflows
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}
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/* Print the results of the simulated sampling according to time */
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Serial.println("Data:");
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PrintVector(vReal, samples, SCL_TIME);
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FFT.windowing(FFTWindow::Hamming, FFTDirection::Forward); /* Weigh data */
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Serial.println("Weighed data:");
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PrintVector(vReal, samples, SCL_TIME);
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FFT.compute(FFTDirection::Forward); /* Compute FFT */
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Serial.println("Computed Real values:");
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PrintVector(vReal, samples, SCL_INDEX);
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Serial.println("Computed Imaginary values:");
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PrintVector(vImag, samples, SCL_INDEX);
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FFT.complexToMagnitude(); /* Compute magnitudes */
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Serial.println("Computed magnitudes:");
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PrintVector(vReal, (samples >> 1), SCL_FREQUENCY);
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double x = FFT.majorPeak();
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Serial.println(x, 6);
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while(1); /* Run Once */
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// delay(2000); /* Repeat after delay */
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}
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void PrintVector(double *vData, uint16_t bufferSize, uint8_t scaleType)
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{
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for (uint16_t i = 0; i < bufferSize; i++)
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{
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double abscissa;
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/* Print abscissa value */
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switch (scaleType)
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{
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case SCL_INDEX:
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abscissa = (i * 1.0);
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break;
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case SCL_TIME:
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abscissa = ((i * 1.0) / samplingFrequency);
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break;
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case SCL_FREQUENCY:
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abscissa = ((i * 1.0 * samplingFrequency) / samples);
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break;
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}
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Serial.print(abscissa, 6);
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if(scaleType==SCL_FREQUENCY)
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Serial.print("Hz");
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Serial.print(" ");
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Serial.println(vData[i], 4);
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}
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Serial.println();
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}
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@ -1,125 +0,0 @@
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/*
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Example of use of the FFT libray to compute FFT for several signals over a range of frequencies.
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The exponent is calculated once before the excecution since it is a constant.
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This saves resources during the excecution of the sketch and reduces the compiled size.
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The sketch shows the time that the computing is taking.
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Copyright (C) 2014 Enrique Condes
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Copyright (C) 2020 Bim Overbohm (header-only, template, speed improvements)
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "arduinoFFT.h"
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/*
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These values can be changed in order to evaluate the functions
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*/
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const uint16_t samples = 64;
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const double sampling = 40;
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const uint8_t amplitude = 4;
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const double startFrequency = 2;
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const double stopFrequency = 16.4;
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const double step_size = 0.1;
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/*
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These are the input and output vectors
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Input vectors receive computed results from FFT
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*/
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double vReal[samples];
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double vImag[samples];
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/* Create FFT object */
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ArduinoFFT<double> FFT = ArduinoFFT<double>(vReal, vImag, samples, sampling);
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unsigned long startTime;
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#define SCL_INDEX 0x00
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#define SCL_TIME 0x01
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#define SCL_FREQUENCY 0x02
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#define SCL_PLOT 0x03
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void setup()
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{
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Serial.begin(115200);
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Serial.println("Ready");
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}
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void loop()
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{
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Serial.println("Frequency\tDetected\ttakes (ms)");
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Serial.println("=======================================\n");
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for(double frequency = startFrequency; frequency<=stopFrequency; frequency+=step_size)
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{
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/* Build raw data */
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double cycles = (((samples-1) * frequency) / sampling);
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for (uint16_t i = 0; i < samples; i++)
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{
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vReal[i] = int8_t((amplitude * (sin((i * (TWO_PI * cycles)) / samples))) / 2.0);
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vImag[i] = 0; //Reset the imaginary values vector for each new frequency
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}
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/*Serial.println("Data:");
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PrintVector(vReal, samples, SCL_TIME);*/
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startTime=millis();
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FFT.windowing(FFTWindow::Hamming, FFTDirection::Forward); /* Weigh data */
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/*Serial.println("Weighed data:");
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PrintVector(vReal, samples, SCL_TIME);*/
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FFT.compute(FFTDirection::Forward); /* Compute FFT */
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/*Serial.println("Computed Real values:");
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PrintVector(vReal, samples, SCL_INDEX);
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Serial.println("Computed Imaginary values:");
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PrintVector(vImag, samples, SCL_INDEX);*/
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FFT.complexToMagnitude(); /* Compute magnitudes */
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/*Serial.println("Computed magnitudes:");
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PrintVector(vReal, (samples >> 1), SCL_FREQUENCY);*/
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double x = FFT.majorPeak();
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Serial.print(frequency);
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Serial.print(": \t\t");
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Serial.print(x, 4);
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Serial.print("\t\t");
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Serial.print(millis()-startTime);
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Serial.println(" ms");
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// delay(2000); /* Repeat after delay */
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}
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while(1); /* Run Once */
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}
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void PrintVector(double *vData, uint16_t bufferSize, uint8_t scaleType)
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{
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for (uint16_t i = 0; i < bufferSize; i++)
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{
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double abscissa;
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/* Print abscissa value */
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switch (scaleType)
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{
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case SCL_INDEX:
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abscissa = (i * 1.0);
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break;
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case SCL_TIME:
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abscissa = ((i * 1.0) / sampling);
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break;
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case SCL_FREQUENCY:
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abscissa = ((i * 1.0 * sampling) / samples);
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break;
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}
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Serial.print(abscissa, 6);
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if(scaleType==SCL_FREQUENCY)
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Serial.print("Hz");
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Serial.print(" ");
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Serial.println(vData[i], 4);
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}
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Serial.println();
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}
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@ -1,114 +0,0 @@
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/*
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Example of use of the FFT libray to compute FFT for a signal sampled through the ADC.
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Copyright (C) 2018 Enrique Condés and Ragnar Ranøyen Homb
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Copyright (C) 2020 Bim Overbohm (header-only, template, speed improvements)
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
|
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
|
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You should have received a copy of the GNU General Public License
|
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "arduinoFFT.h"
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/*
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These values can be changed in order to evaluate the functions
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*/
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#define CHANNEL A0
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const uint16_t samples = 64; //This value MUST ALWAYS be a power of 2
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const double samplingFrequency = 100; //Hz, must be less than 10000 due to ADC
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unsigned int sampling_period_us;
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unsigned long microseconds;
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/*
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These are the input and output vectors
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Input vectors receive computed results from FFT
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*/
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double vReal[samples];
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double vImag[samples];
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/* Create FFT object */
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ArduinoFFT<double> FFT = ArduinoFFT<double>(vReal, vImag, samples, samplingFrequency);
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#define SCL_INDEX 0x00
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#define SCL_TIME 0x01
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#define SCL_FREQUENCY 0x02
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#define SCL_PLOT 0x03
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void setup()
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{
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sampling_period_us = round(1000000*(1.0/samplingFrequency));
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Serial.begin(115200);
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Serial.println("Ready");
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}
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void loop()
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{
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/*SAMPLING*/
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microseconds = micros();
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for(int i=0; i<samples; i++)
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{
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vReal[i] = analogRead(CHANNEL);
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vImag[i] = 0;
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while(micros() - microseconds < sampling_period_us){
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//empty loop
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}
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microseconds += sampling_period_us;
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}
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/* Print the results of the sampling according to time */
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Serial.println("Data:");
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PrintVector(vReal, samples, SCL_TIME);
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FFT.windowing(FFTWindow::Hamming, FFTDirection::Forward); /* Weigh data */
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Serial.println("Weighed data:");
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PrintVector(vReal, samples, SCL_TIME);
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FFT.compute(FFTDirection::Forward); /* Compute FFT */
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Serial.println("Computed Real values:");
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PrintVector(vReal, samples, SCL_INDEX);
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Serial.println("Computed Imaginary values:");
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PrintVector(vImag, samples, SCL_INDEX);
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FFT.complexToMagnitude(); /* Compute magnitudes */
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Serial.println("Computed magnitudes:");
|
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PrintVector(vReal, (samples >> 1), SCL_FREQUENCY);
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double x = FFT.majorPeak();
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Serial.println(x, 6); //Print out what frequency is the most dominant.
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while(1); /* Run Once */
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// delay(2000); /* Repeat after delay */
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}
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void PrintVector(double *vData, uint16_t bufferSize, uint8_t scaleType)
|
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{
|
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for (uint16_t i = 0; i < bufferSize; i++)
|
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{
|
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double abscissa;
|
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/* Print abscissa value */
|
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switch (scaleType)
|
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{
|
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case SCL_INDEX:
|
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abscissa = (i * 1.0);
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break;
|
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case SCL_TIME:
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abscissa = ((i * 1.0) / samplingFrequency);
|
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break;
|
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case SCL_FREQUENCY:
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abscissa = ((i * 1.0 * samplingFrequency) / samples);
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||||
break;
|
||||
}
|
||||
Serial.print(abscissa, 6);
|
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if(scaleType==SCL_FREQUENCY)
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Serial.print("Hz");
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Serial.print(" ");
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Serial.println(vData[i], 4);
|
||||
}
|
||||
Serial.println();
|
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}
|
@ -1,110 +0,0 @@
|
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/*
|
||||
|
||||
Example of use of the FFT libray
|
||||
|
||||
Copyright (C) 2018 Enrique Condes
|
||||
Copyright (C) 2020 Bim Overbohm (header-only, template, speed improvements)
|
||||
|
||||
This program is free software: you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation, either version 3 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
*/
|
||||
|
||||
/*
|
||||
In this example, the Arduino simulates the sampling of a sinusoidal 1000 Hz
|
||||
signal with an amplitude of 100, sampled at 5000 Hz. Samples are stored
|
||||
inside the vReal array. The samples are windowed according to Hamming
|
||||
function. The FFT is computed using the windowed samples. Then the magnitudes
|
||||
of each of the frequencies that compose the signal are calculated. Finally,
|
||||
the frequency spectrum magnitudes are printed. If you use the Arduino IDE
|
||||
serial plotter, you will see a single spike corresponding to the 1000 Hz
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frecuency.
|
||||
*/
|
||||
|
||||
#include "arduinoFFT.h"
|
||||
|
||||
/*
|
||||
These values can be changed in order to evaluate the functions
|
||||
*/
|
||||
const uint16_t samples = 64; //This value MUST ALWAYS be a power of 2
|
||||
const double signalFrequency = 1000;
|
||||
const double samplingFrequency = 5000;
|
||||
const uint8_t amplitude = 100;
|
||||
|
||||
/*
|
||||
These are the input and output vectors
|
||||
Input vectors receive computed results from FFT
|
||||
*/
|
||||
double vReal[samples];
|
||||
double vImag[samples];
|
||||
|
||||
ArduinoFFT<double> FFT = ArduinoFFT<double>(vReal, vImag, samples, samplingFrequency);
|
||||
|
||||
#define SCL_INDEX 0x00
|
||||
#define SCL_TIME 0x01
|
||||
#define SCL_FREQUENCY 0x02
|
||||
#define SCL_PLOT 0x03
|
||||
|
||||
void setup()
|
||||
{
|
||||
Serial.begin(115200);
|
||||
}
|
||||
|
||||
void loop()
|
||||
{
|
||||
/* Build raw data */
|
||||
double cycles = (((samples-1) * signalFrequency) / samplingFrequency); //Number of signal cycles that the sampling will read
|
||||
for (uint16_t i = 0; i < samples; i++)
|
||||
{
|
||||
vReal[i] = int8_t((amplitude * (sin((i * (TWO_PI * cycles)) / samples))) / 2.0);/* Build data with positive and negative values*/
|
||||
//vReal[i] = uint8_t((amplitude * (sin((i * (twoPi * cycles)) / samples) + 1.0)) / 2.0);/* Build data displaced on the Y axis to include only positive values*/
|
||||
vImag[i] = 0.0; //Imaginary part must be zeroed in case of looping to avoid wrong calculations and overflows
|
||||
}
|
||||
FFT.windowing(FFTWindow::Hamming, FFTDirection::Forward); /* Weigh data */
|
||||
FFT.compute(FFTDirection::Forward); /* Compute FFT */
|
||||
FFT.complexToMagnitude(); /* Compute magnitudes */
|
||||
PrintVector(vReal, samples>>1, SCL_PLOT);
|
||||
double x = FFT.majorPeak();
|
||||
while(1); /* Run Once */
|
||||
// delay(2000); /* Repeat after delay */
|
||||
}
|
||||
|
||||
void PrintVector(double *vData, uint16_t bufferSize, uint8_t scaleType)
|
||||
{
|
||||
for (uint16_t i = 0; i < bufferSize; i++)
|
||||
{
|
||||
double abscissa;
|
||||
/* Print abscissa value */
|
||||
switch (scaleType)
|
||||
{
|
||||
case SCL_INDEX:
|
||||
abscissa = (i * 1.0);
|
||||
break;
|
||||
case SCL_TIME:
|
||||
abscissa = ((i * 1.0) / samplingFrequency);
|
||||
break;
|
||||
case SCL_FREQUENCY:
|
||||
abscissa = ((i * 1.0 * samplingFrequency) / samples);
|
||||
break;
|
||||
}
|
||||
if(scaleType!=SCL_PLOT)
|
||||
{
|
||||
Serial.print(abscissa, 6);
|
||||
if(scaleType==SCL_FREQUENCY)
|
||||
Serial.print("Hz");
|
||||
Serial.print(" ");
|
||||
}
|
||||
Serial.println(vData[i], 4);
|
||||
}
|
||||
Serial.println();
|
||||
}
|
@ -1,124 +0,0 @@
|
||||
/*
|
||||
|
||||
Example of use of the FFT libray
|
||||
|
||||
Copyright (C) 2014 Enrique Condes
|
||||
Copyright (C) 2020 Bim Overbohm (header-only, template, speed improvements)
|
||||
|
||||
This program is free software: you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation, either version 3 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
*/
|
||||
|
||||
/*
|
||||
In this example, the Arduino simulates the sampling of a sinusoidal 1000 Hz
|
||||
signal with an amplitude of 100, sampled at 5000 Hz. Samples are stored
|
||||
inside the vReal array. The samples are windowed according to Hamming
|
||||
function. The FFT is computed using the windowed samples. Then the magnitudes
|
||||
of each of the frequencies that compose the signal are calculated. Finally,
|
||||
the frequency with the highest peak is obtained, being that the main frequency
|
||||
present in the signal. This frequency is printed, along with the magnitude of
|
||||
the peak.
|
||||
*/
|
||||
|
||||
#include "arduinoFFT.h"
|
||||
|
||||
/*
|
||||
These values can be changed in order to evaluate the functions
|
||||
*/
|
||||
const uint16_t samples = 64; //This value MUST ALWAYS be a power of 2
|
||||
const double signalFrequency = 1000;
|
||||
const double samplingFrequency = 5000;
|
||||
const uint8_t amplitude = 100;
|
||||
|
||||
/*
|
||||
These are the input and output vectors
|
||||
Input vectors receive computed results from FFT
|
||||
*/
|
||||
double vReal[samples];
|
||||
double vImag[samples];
|
||||
|
||||
/* Create FFT object */
|
||||
ArduinoFFT<double> FFT = ArduinoFFT<double>(vReal, vImag, samples, samplingFrequency);
|
||||
|
||||
#define SCL_INDEX 0x00
|
||||
#define SCL_TIME 0x01
|
||||
#define SCL_FREQUENCY 0x02
|
||||
#define SCL_PLOT 0x03
|
||||
|
||||
void setup()
|
||||
{
|
||||
Serial.begin(115200);
|
||||
Serial.println("Ready");
|
||||
}
|
||||
|
||||
void loop()
|
||||
{
|
||||
/* Build raw data */
|
||||
double cycles = (((samples-1) * signalFrequency) / samplingFrequency); //Number of signal cycles that the sampling will read
|
||||
for (uint16_t i = 0; i < samples; i++)
|
||||
{
|
||||
vReal[i] = int8_t((amplitude * (sin((i * (TWO_PI * cycles)) / samples))) / 2.0);/* Build data with positive and negative values*/
|
||||
//vReal[i] = uint8_t((amplitude * (sin((i * (twoPi * cycles)) / samples) + 1.0)) / 2.0);/* Build data displaced on the Y axis to include only positive values*/
|
||||
vImag[i] = 0.0; //Imaginary part must be zeroed in case of looping to avoid wrong calculations and overflows
|
||||
}
|
||||
/* Print the results of the simulated sampling according to time */
|
||||
Serial.println("Data:");
|
||||
PrintVector(vReal, samples, SCL_TIME);
|
||||
FFT.windowing(FFTWindow::Hamming, FFTDirection::Forward); /* Weigh data */
|
||||
Serial.println("Weighed data:");
|
||||
PrintVector(vReal, samples, SCL_TIME);
|
||||
FFT.compute(FFTDirection::Forward); /* Compute FFT */
|
||||
Serial.println("Computed Real values:");
|
||||
PrintVector(vReal, samples, SCL_INDEX);
|
||||
Serial.println("Computed Imaginary values:");
|
||||
PrintVector(vImag, samples, SCL_INDEX);
|
||||
FFT.complexToMagnitude(); /* Compute magnitudes */
|
||||
Serial.println("Computed magnitudes:");
|
||||
PrintVector(vReal, (samples >> 1), SCL_FREQUENCY);
|
||||
double x;
|
||||
double v;
|
||||
FFT.majorPeak(x, v);
|
||||
Serial.print(x, 6);
|
||||
Serial.print(", ");
|
||||
Serial.println(v, 6);
|
||||
while(1); /* Run Once */
|
||||
// delay(2000); /* Repeat after delay */
|
||||
}
|
||||
|
||||
void PrintVector(double *vData, uint16_t bufferSize, uint8_t scaleType)
|
||||
{
|
||||
for (uint16_t i = 0; i < bufferSize; i++)
|
||||
{
|
||||
double abscissa;
|
||||
/* Print abscissa value */
|
||||
switch (scaleType)
|
||||
{
|
||||
case SCL_INDEX:
|
||||
abscissa = (i * 1.0);
|
||||
break;
|
||||
case SCL_TIME:
|
||||
abscissa = ((i * 1.0) / samplingFrequency);
|
||||
break;
|
||||
case SCL_FREQUENCY:
|
||||
abscissa = ((i * 1.0 * samplingFrequency) / samples);
|
||||
break;
|
||||
}
|
||||
Serial.print(abscissa, 6);
|
||||
if(scaleType==SCL_FREQUENCY)
|
||||
Serial.print("Hz");
|
||||
Serial.print(" ");
|
||||
Serial.println(vData[i], 4);
|
||||
}
|
||||
Serial.println();
|
||||
}
|
@ -1,129 +0,0 @@
|
||||
/*
|
||||
|
||||
Example of use of the FFT libray to compute FFT for a signal sampled through the ADC
|
||||
with speedup through different arduinoFFT options. Based on examples/FFT_03/FFT_03.ino
|
||||
|
||||
Copyright (C) 2020 Bim Overbohm (header-only, template, speed improvements)
|
||||
|
||||
This program is free software: you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation, either version 3 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
*/
|
||||
|
||||
// There are two speedup options for some of the FFT code:
|
||||
|
||||
// Define this to use reciprocal multiplication for division and some more speedups that might decrease precision
|
||||
//#define FFT_SPEED_OVER_PRECISION
|
||||
|
||||
// Define this to use a low-precision square root approximation instead of the regular sqrt() call
|
||||
// This might only work for specific use cases, but is significantly faster. Only works for ArduinoFFT<float>.
|
||||
//#define FFT_SQRT_APPROXIMATION
|
||||
|
||||
#include "arduinoFFT.h"
|
||||
|
||||
/*
|
||||
These values can be changed in order to evaluate the functions
|
||||
*/
|
||||
#define CHANNEL A0
|
||||
const uint16_t samples = 64; //This value MUST ALWAYS be a power of 2
|
||||
const float samplingFrequency = 100; //Hz, must be less than 10000 due to ADC
|
||||
unsigned int sampling_period_us;
|
||||
unsigned long microseconds;
|
||||
|
||||
/*
|
||||
These are the input and output vectors
|
||||
Input vectors receive computed results from FFT
|
||||
*/
|
||||
float vReal[samples];
|
||||
float vImag[samples];
|
||||
|
||||
/*
|
||||
Allocate space for FFT window weighing factors, so they are calculated only the first time windowing() is called.
|
||||
If you don't do this, a lot of calculations are necessary, depending on the window function.
|
||||
*/
|
||||
float weighingFactors[samples];
|
||||
|
||||
/* Create FFT object with weighing factor storage */
|
||||
ArduinoFFT<float> FFT = ArduinoFFT<float>(vReal, vImag, samples, samplingFrequency, weighingFactors);
|
||||
|
||||
#define SCL_INDEX 0x00
|
||||
#define SCL_TIME 0x01
|
||||
#define SCL_FREQUENCY 0x02
|
||||
#define SCL_PLOT 0x03
|
||||
|
||||
void setup()
|
||||
{
|
||||
sampling_period_us = round(1000000*(1.0/samplingFrequency));
|
||||
Serial.begin(115200);
|
||||
Serial.println("Ready");
|
||||
}
|
||||
|
||||
void loop()
|
||||
{
|
||||
/*SAMPLING*/
|
||||
microseconds = micros();
|
||||
for(int i=0; i<samples; i++)
|
||||
{
|
||||
vReal[i] = analogRead(CHANNEL);
|
||||
vImag[i] = 0;
|
||||
while(micros() - microseconds < sampling_period_us){
|
||||
//empty loop
|
||||
}
|
||||
microseconds += sampling_period_us;
|
||||
}
|
||||
/* Print the results of the sampling according to time */
|
||||
Serial.println("Data:");
|
||||
PrintVector(vReal, samples, SCL_TIME);
|
||||
FFT.windowing(FFTWindow::Hamming, FFTDirection::Forward); /* Weigh data */
|
||||
Serial.println("Weighed data:");
|
||||
PrintVector(vReal, samples, SCL_TIME);
|
||||
FFT.compute(FFTDirection::Forward); /* Compute FFT */
|
||||
Serial.println("Computed Real values:");
|
||||
PrintVector(vReal, samples, SCL_INDEX);
|
||||
Serial.println("Computed Imaginary values:");
|
||||
PrintVector(vImag, samples, SCL_INDEX);
|
||||
FFT.complexToMagnitude(); /* Compute magnitudes */
|
||||
Serial.println("Computed magnitudes:");
|
||||
PrintVector(vReal, (samples >> 1), SCL_FREQUENCY);
|
||||
float x = FFT.majorPeak();
|
||||
Serial.println(x, 6); //Print out what frequency is the most dominant.
|
||||
while(1); /* Run Once */
|
||||
// delay(2000); /* Repeat after delay */
|
||||
}
|
||||
|
||||
void PrintVector(float *vData, uint16_t bufferSize, uint8_t scaleType)
|
||||
{
|
||||
for (uint16_t i = 0; i < bufferSize; i++)
|
||||
{
|
||||
float abscissa;
|
||||
/* Print abscissa value */
|
||||
switch (scaleType)
|
||||
{
|
||||
case SCL_INDEX:
|
||||
abscissa = (i * 1.0);
|
||||
break;
|
||||
case SCL_TIME:
|
||||
abscissa = ((i * 1.0) / samplingFrequency);
|
||||
break;
|
||||
case SCL_FREQUENCY:
|
||||
abscissa = ((i * 1.0 * samplingFrequency) / samples);
|
||||
break;
|
||||
}
|
||||
Serial.print(abscissa, 6);
|
||||
if(scaleType==SCL_FREQUENCY)
|
||||
Serial.print("Hz");
|
||||
Serial.print(" ");
|
||||
Serial.println(vData[i], 4);
|
||||
}
|
||||
Serial.println();
|
||||
}
|
@ -1,674 +0,0 @@
|
||||
GNU GENERAL PUBLIC LICENSE
|
||||
Version 3, 29 June 2007
|
||||
|
||||
Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
|
||||
Everyone is permitted to copy and distribute verbatim copies
|
||||
of this license document, but changing it is not allowed.
|
||||
|
||||
Preamble
|
||||
|
||||
The GNU General Public License is a free, copyleft license for
|
||||
software and other kinds of works.
|
||||
|
||||
The licenses for most software and other practical works are designed
|
||||
to take away your freedom to share and change the works. By contrast,
|
||||
the GNU General Public License is intended to guarantee your freedom to
|
||||
share and change all versions of a program--to make sure it remains free
|
||||
software for all its users. We, the Free Software Foundation, use the
|
||||
GNU General Public License for most of our software; it applies also to
|
||||
any other work released this way by its authors. You can apply it to
|
||||
your programs, too.
|
||||
|
||||
When we speak of free software, we are referring to freedom, not
|
||||
price. Our General Public Licenses are designed to make sure that you
|
||||
have the freedom to distribute copies of free software (and charge for
|
||||
them if you wish), that you receive source code or can get it if you
|
||||
want it, that you can change the software or use pieces of it in new
|
||||
free programs, and that you know you can do these things.
|
||||
|
||||
To protect your rights, we need to prevent others from denying you
|
||||
these rights or asking you to surrender the rights. Therefore, you have
|
||||
certain responsibilities if you distribute copies of the software, or if
|
||||
you modify it: responsibilities to respect the freedom of others.
|
||||
|
||||
For example, if you distribute copies of such a program, whether
|
||||
gratis or for a fee, you must pass on to the recipients the same
|
||||
freedoms that you received. You must make sure that they, too, receive
|
||||
or can get the source code. And you must show them these terms so they
|
||||
know their rights.
|
||||
|
||||
Developers that use the GNU GPL protect your rights with two steps:
|
||||
(1) assert copyright on the software, and (2) offer you this License
|
||||
giving you legal permission to copy, distribute and/or modify it.
|
||||
|
||||
For the developers' and authors' protection, the GPL clearly explains
|
||||
that there is no warranty for this free software. For both users' and
|
||||
authors' sake, the GPL requires that modified versions be marked as
|
||||
changed, so that their problems will not be attributed erroneously to
|
||||
authors of previous versions.
|
||||
|
||||
Some devices are designed to deny users access to install or run
|
||||
modified versions of the software inside them, although the manufacturer
|
||||
can do so. This is fundamentally incompatible with the aim of
|
||||
protecting users' freedom to change the software. The systematic
|
||||
pattern of such abuse occurs in the area of products for individuals to
|
||||
use, which is precisely where it is most unacceptable. Therefore, we
|
||||
have designed this version of the GPL to prohibit the practice for those
|
||||
products. If such problems arise substantially in other domains, we
|
||||
stand ready to extend this provision to those domains in future versions
|
||||
of the GPL, as needed to protect the freedom of users.
|
||||
|
||||
Finally, every program is threatened constantly by software patents.
|
||||
States should not allow patents to restrict development and use of
|
||||
software on general-purpose computers, but in those that do, we wish to
|
||||
avoid the special danger that patents applied to a free program could
|
||||
make it effectively proprietary. To prevent this, the GPL assures that
|
||||
patents cannot be used to render the program non-free.
|
||||
|
||||
The precise terms and conditions for copying, distribution and
|
||||
modification follow.
|
||||
|
||||
TERMS AND CONDITIONS
|
||||
|
||||
0. Definitions.
|
||||
|
||||
"This License" refers to version 3 of the GNU General Public License.
|
||||
|
||||
"Copyright" also means copyright-like laws that apply to other kinds of
|
||||
works, such as semiconductor masks.
|
||||
|
||||
"The Program" refers to any copyrightable work licensed under this
|
||||
License. Each licensee is addressed as "you". "Licensees" and
|
||||
"recipients" may be individuals or organizations.
|
||||
|
||||
To "modify" a work means to copy from or adapt all or part of the work
|
||||
in a fashion requiring copyright permission, other than the making of an
|
||||
exact copy. The resulting work is called a "modified version" of the
|
||||
earlier work or a work "based on" the earlier work.
|
||||
|
||||
A "covered work" means either the unmodified Program or a work based
|
||||
on the Program.
|
||||
|
||||
To "propagate" a work means to do anything with it that, without
|
||||
permission, would make you directly or secondarily liable for
|
||||
infringement under applicable copyright law, except executing it on a
|
||||
computer or modifying a private copy. Propagation includes copying,
|
||||
distribution (with or without modification), making available to the
|
||||
public, and in some countries other activities as well.
|
||||
|
||||
To "convey" a work means any kind of propagation that enables other
|
||||
parties to make or receive copies. Mere interaction with a user through
|
||||
a computer network, with no transfer of a copy, is not conveying.
|
||||
|
||||
An interactive user interface displays "Appropriate Legal Notices"
|
||||
to the extent that it includes a convenient and prominently visible
|
||||
feature that (1) displays an appropriate copyright notice, and (2)
|
||||
tells the user that there is no warranty for the work (except to the
|
||||
extent that warranties are provided), that licensees may convey the
|
||||
work under this License, and how to view a copy of this License. If
|
||||
the interface presents a list of user commands or options, such as a
|
||||
menu, a prominent item in the list meets this criterion.
|
||||
|
||||
1. Source Code.
|
||||
|
||||
The "source code" for a work means the preferred form of the work
|
||||
for making modifications to it. "Object code" means any non-source
|
||||
form of a work.
|
||||
|
||||
A "Standard Interface" means an interface that either is an official
|
||||
standard defined by a recognized standards body, or, in the case of
|
||||
interfaces specified for a particular programming language, one that
|
||||
is widely used among developers working in that language.
|
||||
|
||||
The "System Libraries" of an executable work include anything, other
|
||||
than the work as a whole, that (a) is included in the normal form of
|
||||
packaging a Major Component, but which is not part of that Major
|
||||
Component, and (b) serves only to enable use of the work with that
|
||||
Major Component, or to implement a Standard Interface for which an
|
||||
implementation is available to the public in source code form. A
|
||||
"Major Component", in this context, means a major essential component
|
||||
(kernel, window system, and so on) of the specific operating system
|
||||
(if any) on which the executable work runs, or a compiler used to
|
||||
produce the work, or an object code interpreter used to run it.
|
||||
|
||||
The "Corresponding Source" for a work in object code form means all
|
||||
the source code needed to generate, install, and (for an executable
|
||||
work) run the object code and to modify the work, including scripts to
|
||||
control those activities. However, it does not include the work's
|
||||
System Libraries, or general-purpose tools or generally available free
|
||||
programs which are used unmodified in performing those activities but
|
||||
which are not part of the work. For example, Corresponding Source
|
||||
includes interface definition files associated with source files for
|
||||
the work, and the source code for shared libraries and dynamically
|
||||
linked subprograms that the work is specifically designed to require,
|
||||
such as by intimate data communication or control flow between those
|
||||
subprograms and other parts of the work.
|
||||
|
||||
The Corresponding Source need not include anything that users
|
||||
can regenerate automatically from other parts of the Corresponding
|
||||
Source.
|
||||
|
||||
The Corresponding Source for a work in source code form is that
|
||||
same work.
|
||||
|
||||
2. Basic Permissions.
|
||||
|
||||
All rights granted under this License are granted for the term of
|
||||
copyright on the Program, and are irrevocable provided the stated
|
||||
conditions are met. This License explicitly affirms your unlimited
|
||||
permission to run the unmodified Program. The output from running a
|
||||
covered work is covered by this License only if the output, given its
|
||||
content, constitutes a covered work. This License acknowledges your
|
||||
rights of fair use or other equivalent, as provided by copyright law.
|
||||
|
||||
You may make, run and propagate covered works that you do not
|
||||
convey, without conditions so long as your license otherwise remains
|
||||
in force. You may convey covered works to others for the sole purpose
|
||||
of having them make modifications exclusively for you, or provide you
|
||||
with facilities for running those works, provided that you comply with
|
||||
the terms of this License in conveying all material for which you do
|
||||
not control copyright. Those thus making or running the covered works
|
||||
for you must do so exclusively on your behalf, under your direction
|
||||
and control, on terms that prohibit them from making any copies of
|
||||
your copyrighted material outside their relationship with you.
|
||||
|
||||
Conveying under any other circumstances is permitted solely under
|
||||
the conditions stated below. Sublicensing is not allowed; section 10
|
||||
makes it unnecessary.
|
||||
|
||||
3. Protecting Users' Legal Rights From Anti-Circumvention Law.
|
||||
|
||||
No covered work shall be deemed part of an effective technological
|
||||
measure under any applicable law fulfilling obligations under article
|
||||
11 of the WIPO copyright treaty adopted on 20 December 1996, or
|
||||
similar laws prohibiting or restricting circumvention of such
|
||||
measures.
|
||||
|
||||
When you convey a covered work, you waive any legal power to forbid
|
||||
circumvention of technological measures to the extent such circumvention
|
||||
is effected by exercising rights under this License with respect to
|
||||
the covered work, and you disclaim any intention to limit operation or
|
||||
modification of the work as a means of enforcing, against the work's
|
||||
users, your or third parties' legal rights to forbid circumvention of
|
||||
technological measures.
|
||||
|
||||
4. Conveying Verbatim Copies.
|
||||
|
||||
You may convey verbatim copies of the Program's source code as you
|
||||
receive it, in any medium, provided that you conspicuously and
|
||||
appropriately publish on each copy an appropriate copyright notice;
|
||||
keep intact all notices stating that this License and any
|
||||
non-permissive terms added in accord with section 7 apply to the code;
|
||||
keep intact all notices of the absence of any warranty; and give all
|
||||
recipients a copy of this License along with the Program.
|
||||
|
||||
You may charge any price or no price for each copy that you convey,
|
||||
and you may offer support or warranty protection for a fee.
|
||||
|
||||
5. Conveying Modified Source Versions.
|
||||
|
||||
You may convey a work based on the Program, or the modifications to
|
||||
produce it from the Program, in the form of source code under the
|
||||
terms of section 4, provided that you also meet all of these conditions:
|
||||
|
||||
a) The work must carry prominent notices stating that you modified
|
||||
it, and giving a relevant date.
|
||||
|
||||
b) The work must carry prominent notices stating that it is
|
||||
released under this License and any conditions added under section
|
||||
7. This requirement modifies the requirement in section 4 to
|
||||
"keep intact all notices".
|
||||
|
||||
c) You must license the entire work, as a whole, under this
|
||||
License to anyone who comes into possession of a copy. This
|
||||
License will therefore apply, along with any applicable section 7
|
||||
additional terms, to the whole of the work, and all its parts,
|
||||
regardless of how they are packaged. This License gives no
|
||||
permission to license the work in any other way, but it does not
|
||||
invalidate such permission if you have separately received it.
|
||||
|
||||
d) If the work has interactive user interfaces, each must display
|
||||
Appropriate Legal Notices; however, if the Program has interactive
|
||||
interfaces that do not display Appropriate Legal Notices, your
|
||||
work need not make them do so.
|
||||
|
||||
A compilation of a covered work with other separate and independent
|
||||
works, which are not by their nature extensions of the covered work,
|
||||
and which are not combined with it such as to form a larger program,
|
||||
in or on a volume of a storage or distribution medium, is called an
|
||||
"aggregate" if the compilation and its resulting copyright are not
|
||||
used to limit the access or legal rights of the compilation's users
|
||||
beyond what the individual works permit. Inclusion of a covered work
|
||||
in an aggregate does not cause this License to apply to the other
|
||||
parts of the aggregate.
|
||||
|
||||
6. Conveying Non-Source Forms.
|
||||
|
||||
You may convey a covered work in object code form under the terms
|
||||
of sections 4 and 5, provided that you also convey the
|
||||
machine-readable Corresponding Source under the terms of this License,
|
||||
in one of these ways:
|
||||
|
||||
a) Convey the object code in, or embodied in, a physical product
|
||||
(including a physical distribution medium), accompanied by the
|
||||
Corresponding Source fixed on a durable physical medium
|
||||
customarily used for software interchange.
|
||||
|
||||
b) Convey the object code in, or embodied in, a physical product
|
||||
(including a physical distribution medium), accompanied by a
|
||||
written offer, valid for at least three years and valid for as
|
||||
long as you offer spare parts or customer support for that product
|
||||
model, to give anyone who possesses the object code either (1) a
|
||||
copy of the Corresponding Source for all the software in the
|
||||
product that is covered by this License, on a durable physical
|
||||
medium customarily used for software interchange, for a price no
|
||||
more than your reasonable cost of physically performing this
|
||||
conveying of source, or (2) access to copy the
|
||||
Corresponding Source from a network server at no charge.
|
||||
|
||||
c) Convey individual copies of the object code with a copy of the
|
||||
written offer to provide the Corresponding Source. This
|
||||
alternative is allowed only occasionally and noncommercially, and
|
||||
only if you received the object code with such an offer, in accord
|
||||
with subsection 6b.
|
||||
|
||||
d) Convey the object code by offering access from a designated
|
||||
place (gratis or for a charge), and offer equivalent access to the
|
||||
Corresponding Source in the same way through the same place at no
|
||||
further charge. You need not require recipients to copy the
|
||||
Corresponding Source along with the object code. If the place to
|
||||
copy the object code is a network server, the Corresponding Source
|
||||
may be on a different server (operated by you or a third party)
|
||||
that supports equivalent copying facilities, provided you maintain
|
||||
clear directions next to the object code saying where to find the
|
||||
Corresponding Source. Regardless of what server hosts the
|
||||
Corresponding Source, you remain obligated to ensure that it is
|
||||
available for as long as needed to satisfy these requirements.
|
||||
|
||||
e) Convey the object code using peer-to-peer transmission, provided
|
||||
you inform other peers where the object code and Corresponding
|
||||
Source of the work are being offered to the general public at no
|
||||
charge under subsection 6d.
|
||||
|
||||
A separable portion of the object code, whose source code is excluded
|
||||
from the Corresponding Source as a System Library, need not be
|
||||
included in conveying the object code work.
|
||||
|
||||
A "User Product" is either (1) a "consumer product", which means any
|
||||
tangible personal property which is normally used for personal, family,
|
||||
or household purposes, or (2) anything designed or sold for incorporation
|
||||
into a dwelling. In determining whether a product is a consumer product,
|
||||
doubtful cases shall be resolved in favor of coverage. For a particular
|
||||
product received by a particular user, "normally used" refers to a
|
||||
typical or common use of that class of product, regardless of the status
|
||||
of the particular user or of the way in which the particular user
|
||||
actually uses, or expects or is expected to use, the product. A product
|
||||
is a consumer product regardless of whether the product has substantial
|
||||
commercial, industrial or non-consumer uses, unless such uses represent
|
||||
the only significant mode of use of the product.
|
||||
|
||||
"Installation Information" for a User Product means any methods,
|
||||
procedures, authorization keys, or other information required to install
|
||||
and execute modified versions of a covered work in that User Product from
|
||||
a modified version of its Corresponding Source. The information must
|
||||
suffice to ensure that the continued functioning of the modified object
|
||||
code is in no case prevented or interfered with solely because
|
||||
modification has been made.
|
||||
|
||||
If you convey an object code work under this section in, or with, or
|
||||
specifically for use in, a User Product, and the conveying occurs as
|
||||
part of a transaction in which the right of possession and use of the
|
||||
User Product is transferred to the recipient in perpetuity or for a
|
||||
fixed term (regardless of how the transaction is characterized), the
|
||||
Corresponding Source conveyed under this section must be accompanied
|
||||
by the Installation Information. But this requirement does not apply
|
||||
if neither you nor any third party retains the ability to install
|
||||
modified object code on the User Product (for example, the work has
|
||||
been installed in ROM).
|
||||
|
||||
The requirement to provide Installation Information does not include a
|
||||
requirement to continue to provide support service, warranty, or updates
|
||||
for a work that has been modified or installed by the recipient, or for
|
||||
the User Product in which it has been modified or installed. Access to a
|
||||
network may be denied when the modification itself materially and
|
||||
adversely affects the operation of the network or violates the rules and
|
||||
protocols for communication across the network.
|
||||
|
||||
Corresponding Source conveyed, and Installation Information provided,
|
||||
in accord with this section must be in a format that is publicly
|
||||
documented (and with an implementation available to the public in
|
||||
source code form), and must require no special password or key for
|
||||
unpacking, reading or copying.
|
||||
|
||||
7. Additional Terms.
|
||||
|
||||
"Additional permissions" are terms that supplement the terms of this
|
||||
License by making exceptions from one or more of its conditions.
|
||||
Additional permissions that are applicable to the entire Program shall
|
||||
be treated as though they were included in this License, to the extent
|
||||
that they are valid under applicable law. If additional permissions
|
||||
apply only to part of the Program, that part may be used separately
|
||||
under those permissions, but the entire Program remains governed by
|
||||
this License without regard to the additional permissions.
|
||||
|
||||
When you convey a copy of a covered work, you may at your option
|
||||
remove any additional permissions from that copy, or from any part of
|
||||
it. (Additional permissions may be written to require their own
|
||||
removal in certain cases when you modify the work.) You may place
|
||||
additional permissions on material, added by you to a covered work,
|
||||
for which you have or can give appropriate copyright permission.
|
||||
|
||||
Notwithstanding any other provision of this License, for material you
|
||||
add to a covered work, you may (if authorized by the copyright holders of
|
||||
that material) supplement the terms of this License with terms:
|
||||
|
||||
a) Disclaiming warranty or limiting liability differently from the
|
||||
terms of sections 15 and 16 of this License; or
|
||||
|
||||
b) Requiring preservation of specified reasonable legal notices or
|
||||
author attributions in that material or in the Appropriate Legal
|
||||
Notices displayed by works containing it; or
|
||||
|
||||
c) Prohibiting misrepresentation of the origin of that material, or
|
||||
requiring that modified versions of such material be marked in
|
||||
reasonable ways as different from the original version; or
|
||||
|
||||
d) Limiting the use for publicity purposes of names of licensors or
|
||||
authors of the material; or
|
||||
|
||||
e) Declining to grant rights under trademark law for use of some
|
||||
trade names, trademarks, or service marks; or
|
||||
|
||||
f) Requiring indemnification of licensors and authors of that
|
||||
material by anyone who conveys the material (or modified versions of
|
||||
it) with contractual assumptions of liability to the recipient, for
|
||||
any liability that these contractual assumptions directly impose on
|
||||
those licensors and authors.
|
||||
|
||||
All other non-permissive additional terms are considered "further
|
||||
restrictions" within the meaning of section 10. If the Program as you
|
||||
received it, or any part of it, contains a notice stating that it is
|
||||
governed by this License along with a term that is a further
|
||||
restriction, you may remove that term. If a license document contains
|
||||
a further restriction but permits relicensing or conveying under this
|
||||
License, you may add to a covered work material governed by the terms
|
||||
of that license document, provided that the further restriction does
|
||||
not survive such relicensing or conveying.
|
||||
|
||||
If you add terms to a covered work in accord with this section, you
|
||||
must place, in the relevant source files, a statement of the
|
||||
additional terms that apply to those files, or a notice indicating
|
||||
where to find the applicable terms.
|
||||
|
||||
Additional terms, permissive or non-permissive, may be stated in the
|
||||
form of a separately written license, or stated as exceptions;
|
||||
the above requirements apply either way.
|
||||
|
||||
8. Termination.
|
||||
|
||||
You may not propagate or modify a covered work except as expressly
|
||||
provided under this License. Any attempt otherwise to propagate or
|
||||
modify it is void, and will automatically terminate your rights under
|
||||
this License (including any patent licenses granted under the third
|
||||
paragraph of section 11).
|
||||
|
||||
However, if you cease all violation of this License, then your
|
||||
license from a particular copyright holder is reinstated (a)
|
||||
provisionally, unless and until the copyright holder explicitly and
|
||||
finally terminates your license, and (b) permanently, if the copyright
|
||||
holder fails to notify you of the violation by some reasonable means
|
||||
prior to 60 days after the cessation.
|
||||
|
||||
Moreover, your license from a particular copyright holder is
|
||||
reinstated permanently if the copyright holder notifies you of the
|
||||
violation by some reasonable means, this is the first time you have
|
||||
received notice of violation of this License (for any work) from that
|
||||
copyright holder, and you cure the violation prior to 30 days after
|
||||
your receipt of the notice.
|
||||
|
||||
Termination of your rights under this section does not terminate the
|
||||
licenses of parties who have received copies or rights from you under
|
||||
this License. If your rights have been terminated and not permanently
|
||||
reinstated, you do not qualify to receive new licenses for the same
|
||||
material under section 10.
|
||||
|
||||
9. Acceptance Not Required for Having Copies.
|
||||
|
||||
You are not required to accept this License in order to receive or
|
||||
run a copy of the Program. Ancillary propagation of a covered work
|
||||
occurring solely as a consequence of using peer-to-peer transmission
|
||||
to receive a copy likewise does not require acceptance. However,
|
||||
nothing other than this License grants you permission to propagate or
|
||||
modify any covered work. These actions infringe copyright if you do
|
||||
not accept this License. Therefore, by modifying or propagating a
|
||||
covered work, you indicate your acceptance of this License to do so.
|
||||
|
||||
10. Automatic Licensing of Downstream Recipients.
|
||||
|
||||
Each time you convey a covered work, the recipient automatically
|
||||
receives a license from the original licensors, to run, modify and
|
||||
propagate that work, subject to this License. You are not responsible
|
||||
for enforcing compliance by third parties with this License.
|
||||
|
||||
An "entity transaction" is a transaction transferring control of an
|
||||
organization, or substantially all assets of one, or subdividing an
|
||||
organization, or merging organizations. If propagation of a covered
|
||||
work results from an entity transaction, each party to that
|
||||
transaction who receives a copy of the work also receives whatever
|
||||
licenses to the work the party's predecessor in interest had or could
|
||||
give under the previous paragraph, plus a right to possession of the
|
||||
Corresponding Source of the work from the predecessor in interest, if
|
||||
the predecessor has it or can get it with reasonable efforts.
|
||||
|
||||
You may not impose any further restrictions on the exercise of the
|
||||
rights granted or affirmed under this License. For example, you may
|
||||
not impose a license fee, royalty, or other charge for exercise of
|
||||
rights granted under this License, and you may not initiate litigation
|
||||
(including a cross-claim or counterclaim in a lawsuit) alleging that
|
||||
any patent claim is infringed by making, using, selling, offering for
|
||||
sale, or importing the Program or any portion of it.
|
||||
|
||||
11. Patents.
|
||||
|
||||
A "contributor" is a copyright holder who authorizes use under this
|
||||
License of the Program or a work on which the Program is based. The
|
||||
work thus licensed is called the contributor's "contributor version".
|
||||
|
||||
A contributor's "essential patent claims" are all patent claims
|
||||
owned or controlled by the contributor, whether already acquired or
|
||||
hereafter acquired, that would be infringed by some manner, permitted
|
||||
by this License, of making, using, or selling its contributor version,
|
||||
but do not include claims that would be infringed only as a
|
||||
consequence of further modification of the contributor version. For
|
||||
purposes of this definition, "control" includes the right to grant
|
||||
patent sublicenses in a manner consistent with the requirements of
|
||||
this License.
|
||||
|
||||
Each contributor grants you a non-exclusive, worldwide, royalty-free
|
||||
patent license under the contributor's essential patent claims, to
|
||||
make, use, sell, offer for sale, import and otherwise run, modify and
|
||||
propagate the contents of its contributor version.
|
||||
|
||||
In the following three paragraphs, a "patent license" is any express
|
||||
agreement or commitment, however denominated, not to enforce a patent
|
||||
(such as an express permission to practice a patent or covenant not to
|
||||
sue for patent infringement). To "grant" such a patent license to a
|
||||
party means to make such an agreement or commitment not to enforce a
|
||||
patent against the party.
|
||||
|
||||
If you convey a covered work, knowingly relying on a patent license,
|
||||
and the Corresponding Source of the work is not available for anyone
|
||||
to copy, free of charge and under the terms of this License, through a
|
||||
publicly available network server or other readily accessible means,
|
||||
then you must either (1) cause the Corresponding Source to be so
|
||||
available, or (2) arrange to deprive yourself of the benefit of the
|
||||
patent license for this particular work, or (3) arrange, in a manner
|
||||
consistent with the requirements of this License, to extend the patent
|
||||
license to downstream recipients. "Knowingly relying" means you have
|
||||
actual knowledge that, but for the patent license, your conveying the
|
||||
covered work in a country, or your recipient's use of the covered work
|
||||
in a country, would infringe one or more identifiable patents in that
|
||||
country that you have reason to believe are valid.
|
||||
|
||||
If, pursuant to or in connection with a single transaction or
|
||||
arrangement, you convey, or propagate by procuring conveyance of, a
|
||||
covered work, and grant a patent license to some of the parties
|
||||
receiving the covered work authorizing them to use, propagate, modify
|
||||
or convey a specific copy of the covered work, then the patent license
|
||||
you grant is automatically extended to all recipients of the covered
|
||||
work and works based on it.
|
||||
|
||||
A patent license is "discriminatory" if it does not include within
|
||||
the scope of its coverage, prohibits the exercise of, or is
|
||||
conditioned on the non-exercise of one or more of the rights that are
|
||||
specifically granted under this License. You may not convey a covered
|
||||
work if you are a party to an arrangement with a third party that is
|
||||
in the business of distributing software, under which you make payment
|
||||
to the third party based on the extent of your activity of conveying
|
||||
the work, and under which the third party grants, to any of the
|
||||
parties who would receive the covered work from you, a discriminatory
|
||||
patent license (a) in connection with copies of the covered work
|
||||
conveyed by you (or copies made from those copies), or (b) primarily
|
||||
for and in connection with specific products or compilations that
|
||||
contain the covered work, unless you entered into that arrangement,
|
||||
or that patent license was granted, prior to 28 March 2007.
|
||||
|
||||
Nothing in this License shall be construed as excluding or limiting
|
||||
any implied license or other defenses to infringement that may
|
||||
otherwise be available to you under applicable patent law.
|
||||
|
||||
12. No Surrender of Others' Freedom.
|
||||
|
||||
If conditions are imposed on you (whether by court order, agreement or
|
||||
otherwise) that contradict the conditions of this License, they do not
|
||||
excuse you from the conditions of this License. If you cannot convey a
|
||||
covered work so as to satisfy simultaneously your obligations under this
|
||||
License and any other pertinent obligations, then as a consequence you may
|
||||
not convey it at all. For example, if you agree to terms that obligate you
|
||||
to collect a royalty for further conveying from those to whom you convey
|
||||
the Program, the only way you could satisfy both those terms and this
|
||||
License would be to refrain entirely from conveying the Program.
|
||||
|
||||
13. Use with the GNU Affero General Public License.
|
||||
|
||||
Notwithstanding any other provision of this License, you have
|
||||
permission to link or combine any covered work with a work licensed
|
||||
under version 3 of the GNU Affero General Public License into a single
|
||||
combined work, and to convey the resulting work. The terms of this
|
||||
License will continue to apply to the part which is the covered work,
|
||||
but the special requirements of the GNU Affero General Public License,
|
||||
section 13, concerning interaction through a network will apply to the
|
||||
combination as such.
|
||||
|
||||
14. Revised Versions of this License.
|
||||
|
||||
The Free Software Foundation may publish revised and/or new versions of
|
||||
the GNU General Public License from time to time. Such new versions will
|
||||
be similar in spirit to the present version, but may differ in detail to
|
||||
address new problems or concerns.
|
||||
|
||||
Each version is given a distinguishing version number. If the
|
||||
Program specifies that a certain numbered version of the GNU General
|
||||
Public License "or any later version" applies to it, you have the
|
||||
option of following the terms and conditions either of that numbered
|
||||
version or of any later version published by the Free Software
|
||||
Foundation. If the Program does not specify a version number of the
|
||||
GNU General Public License, you may choose any version ever published
|
||||
by the Free Software Foundation.
|
||||
|
||||
If the Program specifies that a proxy can decide which future
|
||||
versions of the GNU General Public License can be used, that proxy's
|
||||
public statement of acceptance of a version permanently authorizes you
|
||||
to choose that version for the Program.
|
||||
|
||||
Later license versions may give you additional or different
|
||||
permissions. However, no additional obligations are imposed on any
|
||||
author or copyright holder as a result of your choosing to follow a
|
||||
later version.
|
||||
|
||||
15. Disclaimer of Warranty.
|
||||
|
||||
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
|
||||
APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
|
||||
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
|
||||
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
|
||||
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
||||
PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
|
||||
IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
|
||||
ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
|
||||
|
||||
16. Limitation of Liability.
|
||||
|
||||
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
|
||||
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
|
||||
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
|
||||
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
|
||||
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
|
||||
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
|
||||
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
|
||||
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
|
||||
SUCH DAMAGES.
|
||||
|
||||
17. Interpretation of Sections 15 and 16.
|
||||
|
||||
If the disclaimer of warranty and limitation of liability provided
|
||||
above cannot be given local legal effect according to their terms,
|
||||
reviewing courts shall apply local law that most closely approximates
|
||||
an absolute waiver of all civil liability in connection with the
|
||||
Program, unless a warranty or assumption of liability accompanies a
|
||||
copy of the Program in return for a fee.
|
||||
|
||||
END OF TERMS AND CONDITIONS
|
||||
|
||||
How to Apply These Terms to Your New Programs
|
||||
|
||||
If you develop a new program, and you want it to be of the greatest
|
||||
possible use to the public, the best way to achieve this is to make it
|
||||
free software which everyone can redistribute and change under these terms.
|
||||
|
||||
To do so, attach the following notices to the program. It is safest
|
||||
to attach them to the start of each source file to most effectively
|
||||
state the exclusion of warranty; and each file should have at least
|
||||
the "copyright" line and a pointer to where the full notice is found.
|
||||
|
||||
{one line to give the program's name and a brief idea of what it does.}
|
||||
Copyright (C) {year} {name of author}
|
||||
|
||||
This program is free software: you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation, either version 3 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
Also add information on how to contact you by electronic and paper mail.
|
||||
|
||||
If the program does terminal interaction, make it output a short
|
||||
notice like this when it starts in an interactive mode:
|
||||
|
||||
{project} Copyright (C) {year} {fullname}
|
||||
This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
|
||||
This is free software, and you are welcome to redistribute it
|
||||
under certain conditions; type `show c' for details.
|
||||
|
||||
The hypothetical commands `show w' and `show c' should show the appropriate
|
||||
parts of the General Public License. Of course, your program's commands
|
||||
might be different; for a GUI interface, you would use an "about box".
|
||||
|
||||
You should also get your employer (if you work as a programmer) or school,
|
||||
if any, to sign a "copyright disclaimer" for the program, if necessary.
|
||||
For more information on this, and how to apply and follow the GNU GPL, see
|
||||
<http://www.gnu.org/licenses/>.
|
||||
|
||||
The GNU General Public License does not permit incorporating your program
|
||||
into proprietary programs. If your program is a subroutine library, you
|
||||
may consider it more useful to permit linking proprietary applications with
|
||||
the library. If this is what you want to do, use the GNU Lesser General
|
||||
Public License instead of this License. But first, please read
|
||||
<http://www.gnu.org/philosophy/why-not-lgpl.html>.
|
@ -1,129 +0,0 @@
|
||||
arduinoFFT
|
||||
==========
|
||||
|
||||
# Fast Fourier Transform for Arduino
|
||||
|
||||
This is a fork from https://code.google.com/p/makefurt/ which has been abandoned since 2011.
|
||||
~~This is a C++ library for Arduino for computing FFT.~~ Now it works both on Arduino and C projects. This is version 2.0 of the library, which has a different [API](#api). See here [how to migrate from 1.x to 2.x](#migrating-from-1x-to-2x).
|
||||
Tested on Arduino 1.6.11 and 1.8.10.
|
||||
|
||||
## Installation on Arduino
|
||||
|
||||
Use the Arduino Library Manager to install and keep it updated. Just look for arduinoFFT. Only for Arduino 1.5+
|
||||
|
||||
## Manual installation on Arduino
|
||||
|
||||
To install this library, just place this entire folder as a subfolder in your Arduino installation. When installed, this library should look like:
|
||||
|
||||
`Arduino\libraries\arduinoFTT` (this library's folder)
|
||||
`Arduino\libraries\arduinoFTT\src\arduinoFTT.h` (the library header file. include this in your project)
|
||||
`Arduino\libraries\arduinoFTT\keywords.txt` (the syntax coloring file)
|
||||
`Arduino\libraries\arduinoFTT\Examples` (the examples in the "open" menu)
|
||||
`Arduino\libraries\arduinoFTT\LICENSE` (GPL license file)
|
||||
`Arduino\libraries\arduinoFTT\README.md` (this file)
|
||||
|
||||
## Building on Arduino
|
||||
|
||||
After this library is installed, you just have to start the Arduino application.
|
||||
You may see a few warning messages as it's built.
|
||||
To use this library in a sketch, go to the Sketch | Import Library menu and
|
||||
select arduinoFTT. This will add a corresponding line to the top of your sketch:
|
||||
|
||||
`#include <arduinoFTT.h>`
|
||||
|
||||
## API
|
||||
|
||||
* ```ArduinoFFT(T *vReal, T *vImag, uint_fast16_t samples, T samplingFrequency, T * weighingFactors = nullptr);```
|
||||
Constructor.
|
||||
The type `T` can be `float` or `double`. `vReal` and `vImag` are pointers to arrays of real and imaginary data and have to be allocated outside of ArduinoFFT. `samples` is the number of samples in `vReal` and `vImag` and `weighingFactors` (if specified). `samplingFrequency` is the sample frequency of the data. `weighingFactors` can optionally be specified to cache weighing factors for the windowing function. This speeds up repeated calls to **windowing()** significantly. You can deallocate `vReal` and `vImag` after you are done using the library, or only use specific library functions that only need one of those arrays.
|
||||
|
||||
```C++
|
||||
const uint32_t nrOfSamples = 1024;
|
||||
auto real = new float[nrOfSamples];
|
||||
auto imag = new float[nrOfSamples];
|
||||
auto fft = ArduinoFFT<float>(real, imag, nrOfSamples, 10000);
|
||||
// ... fill real + imag and use it ...
|
||||
fft.compute();
|
||||
fft.complexToMagnitude();
|
||||
delete [] imag;
|
||||
// ... continue using real and only functions that use real ...
|
||||
auto peak = fft.majorPeak();
|
||||
```
|
||||
* ```~ArduinoFFT()```
|
||||
Destructor.
|
||||
* ```void complexToMagnitude() const;```
|
||||
Convert complex values to their magnitude and store in vReal. Uses vReal and vImag.
|
||||
* ```void compute(FFTDirection dir) const;```
|
||||
Calcuates the Fast Fourier Transform. Uses vReal and vImag.
|
||||
* ```void dcRemoval() const;```
|
||||
Removes the DC component from the sample data. Uses vReal.
|
||||
* ```T majorPeak() const;```
|
||||
Returns the frequency of the biggest spike in the analyzed signal. Uses vReal.
|
||||
* ```void majorPeak(T &frequency, T &value) const;```
|
||||
Returns the frequency and the value of the biggest spike in the analyzed signal. Uses vReal.
|
||||
* ```uint8_t revision() const;```
|
||||
Returns the library revision.
|
||||
* ```void setArrays(T *vReal, T *vImag);```
|
||||
Replace the data array pointers.
|
||||
* ```void windowing(FFTWindow windowType, FFTDirection dir, bool withCompensation = false);```
|
||||
Performs a windowing function on the values array. Uses vReal. The possible windowing options are:
|
||||
* Rectangle
|
||||
* Hamming
|
||||
* Hann
|
||||
* Triangle
|
||||
* Nuttall
|
||||
* Blackman
|
||||
* Blackman_Nuttall
|
||||
* Blackman_Harris
|
||||
* Flat_top
|
||||
* Welch
|
||||
|
||||
If `withCompensation` == true, the following compensation factors are used:
|
||||
* Rectangle: 1.0 * 2.0
|
||||
* Hamming: 1.8549343278 * 2.0
|
||||
* Hann: 1.8554726898 * 2.0
|
||||
* Triangle: 2.0039186079 * 2.0
|
||||
* Nuttall: 2.8163172034 * 2.0
|
||||
* Blackman: 2.3673474360 * 2.0
|
||||
* Blackman Nuttall: 2.7557840395 * 2.0
|
||||
* Blackman Harris: 2.7929062517 * 2.0
|
||||
* Flat top: 3.5659039231 * 2.0
|
||||
* Welch: 1.5029392863 * 2.0
|
||||
|
||||
## Special flags
|
||||
|
||||
You can define these before including arduinoFFT.h:
|
||||
|
||||
* #define FFT_SPEED_OVER_PRECISION
|
||||
Define this to use reciprocal multiplication for division and some more speedups that might decrease precision.
|
||||
|
||||
* #define FFT_SQRT_APPROXIMATION
|
||||
Define this to use a low-precision square root approximation instead of the regular sqrt() call. This might only work for specific use cases, but is significantly faster. Only works if `T == float`.
|
||||
|
||||
See the `FFT_speedup.ino` example in `Examples/FFT_speedup/FFT_speedup.ino`.
|
||||
|
||||
# Migrating from 1.x to 2.x
|
||||
|
||||
* The function signatures where you could pass in pointers were deprecated and have been removed. Pass in pointers to your real / imaginary array in the ArduinoFFT() constructor. If you have the need to replace those pointers during usage of the library (e.g. to free memory) you can do the following:
|
||||
|
||||
```C++
|
||||
const uint32_t nrOfSamples = 1024;
|
||||
auto real = new float[nrOfSamples];
|
||||
auto imag = new float[nrOfSamples];
|
||||
auto fft = ArduinoFFT<float>(real, imag, nrOfSamples, 10000);
|
||||
// ... fill real + imag and use it ...
|
||||
fft.compute();
|
||||
fft.complexToMagnitude();
|
||||
delete [] real;
|
||||
// ... replace vReal in library with imag ...
|
||||
fft.setArrays(imag, nullptr);
|
||||
// ... keep doing whatever ...
|
||||
```
|
||||
* All function names are camelCase case now (start with lower-case character), e.g. "windowing()" instead of "Windowing()".
|
||||
|
||||
## TODO
|
||||
* Ratio table for windowing function.
|
||||
* Document windowing functions advantages and disadvantages.
|
||||
* Optimize usage and arguments.
|
||||
* Add new windowing functions.
|
||||
* ~~Spectrum table?~~
|
@ -1,40 +0,0 @@
|
||||
02/22/20 v1.9.2
|
||||
Fix compilation on AVR systems.
|
||||
|
||||
02/22/20 v1.9.1
|
||||
Add setArrays() function because of issue #32.
|
||||
Add API migration info to README and improve README.
|
||||
Use better sqrtf() approximation.
|
||||
|
||||
02/19/20 v1.9.0
|
||||
Remove deprecated API. Consistent renaming of functions to lowercase.
|
||||
Make template to be able to use float or double type (float brings a ~70% speed increase on ESP32).
|
||||
Add option to provide cache for window function weighing factors (~50% speed increase on ESP32).
|
||||
Add some #defines to enable math approximisations to further speed up code (~40% speed increase on ESP32).
|
||||
|
||||
01/27/20 v1.5.5
|
||||
Lookup table for constants c1 and c2 used during FFT comupting. This increases the FFT computing speed in around 5%.
|
||||
|
||||
02/10/18 v1.4
|
||||
Transition version. Minor optimization to functions. New API. Deprecation of old functions.
|
||||
|
||||
12/06/18 v1.3
|
||||
Add support for mbed development boards.
|
||||
|
||||
09/04/17 v1.2.3
|
||||
Finally solves the issue of Arduino IDE not correctly detecting and highlighting the keywords.
|
||||
|
||||
09/03/17 v1.2.2
|
||||
Solves a format issue in keywords.txt that prevented keywords from being detected.
|
||||
|
||||
08/28/17 v1.2.1
|
||||
Fix to issues 6 and 7. Not cleaning the imaginary vector after each cycle leaded to erroneous calculations and could cause buffer overflows.
|
||||
|
||||
08/04/17 v1.2
|
||||
Fix to bug preventing the number of samples to be greater than 128. New logical limit is 32768 samples but it is bound to the RAM on the chip.
|
||||
|
||||
05/12/17 v1.1
|
||||
Fix issue that prevented installation through the Arduino Library Manager interface.
|
||||
|
||||
05/11/17 v1.0
|
||||
Initial commit to Arduino Library Manager.
|
@ -1,41 +0,0 @@
|
||||
#######################################
|
||||
# Syntax Coloring Map For arduinoFFT
|
||||
#######################################
|
||||
|
||||
#######################################
|
||||
# Datatypes (KEYWORD1)
|
||||
#######################################
|
||||
|
||||
ArduinoFFT KEYWORD1
|
||||
FFTDirection KEYWORD1
|
||||
FFTWindow KEYWORD1
|
||||
|
||||
#######################################
|
||||
# Methods and Functions (KEYWORD2)
|
||||
#######################################
|
||||
|
||||
complexToMagnitude KEYWORD2
|
||||
compute KEYWORD2
|
||||
dcRemoval KEYWORD2
|
||||
windowing KEYWORD2
|
||||
exponent KEYWORD2
|
||||
revision KEYWORD2
|
||||
majorPeak KEYWORD2
|
||||
setArrays KEYWORD2
|
||||
|
||||
#######################################
|
||||
# Constants (LITERAL1)
|
||||
#######################################
|
||||
|
||||
Forward LITERAL1
|
||||
Reverse LITERAL1
|
||||
Rectangle LITERAL1
|
||||
Hamming LITERAL1
|
||||
Hann LITERAL1
|
||||
Triangle LITERAL1
|
||||
Nuttall LITERAL1
|
||||
Blackman LITERAL1
|
||||
Blackman_Nuttall LITERAL1
|
||||
Blackman_Harris LITERAL1
|
||||
Flat_top LITERAL1
|
||||
Welch LITERAL1
|
@ -1,31 +0,0 @@
|
||||
{
|
||||
"name": "arduinoFFT",
|
||||
"keywords": "FFT, Fourier, FDT, frequency",
|
||||
"description": "A library for implementing floating point Fast Fourier Transform calculations.",
|
||||
"repository":
|
||||
{
|
||||
"type": "git",
|
||||
"url": "https://github.com/kosme/arduinoFFT.git"
|
||||
},
|
||||
"authors":
|
||||
[
|
||||
{
|
||||
"name": "Enrique Condes",
|
||||
"email": "enrique@shapeoko.com",
|
||||
"maintainer": true
|
||||
},
|
||||
{
|
||||
"name": "Didier Longueville",
|
||||
"url": "http://www.arduinoos.com/",
|
||||
"email": "contact@arduinoos.com"
|
||||
},
|
||||
{
|
||||
"name": "Bim Overbohm",
|
||||
"url": "https://github.com/HorstBaerbel",
|
||||
"email": "bim.overbohm@googlemail.com"
|
||||
}
|
||||
],
|
||||
"version": "1.9.2",
|
||||
"frameworks": ["arduino","mbed","espidf"],
|
||||
"platforms": "*"
|
||||
}
|
@ -1,10 +0,0 @@
|
||||
name=arduinoFFT
|
||||
version=1.9.2
|
||||
author=Enrique Condes <enrique@shapeoko.com>
|
||||
maintainer=Enrique Condes <enrique@shapeoko.com>
|
||||
sentence=A library for implementing floating point Fast Fourier Transform calculations on Arduino.
|
||||
paragraph=With this library you can calculate the frequency of a sampled signal.
|
||||
category=Data Processing
|
||||
url=https://github.com/kosme/arduinoFFT
|
||||
architectures=*
|
||||
includes=arduinoFFT.h
|
1
src/libs/arduinoFFT-develop/src/.gitignore
vendored
1
src/libs/arduinoFFT-develop/src/.gitignore
vendored
@ -1 +0,0 @@
|
||||
/arduinoFFT.h.gch
|
@ -1,498 +0,0 @@
|
||||
/*
|
||||
|
||||
FFT library
|
||||
Copyright (C) 2010 Didier Longueville
|
||||
Copyright (C) 2014 Enrique Condes
|
||||
Copyright (C) 2020 Bim Overbohm (header-only, template, speed improvements)
|
||||
|
||||
This program is free software: you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation, either version 3 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
*/
|
||||
|
||||
#ifndef ArduinoFFT_h /* Prevent loading library twice */
|
||||
#define ArduinoFFT_h
|
||||
#ifdef ARDUINO
|
||||
#if ARDUINO >= 100
|
||||
#include "Arduino.h"
|
||||
#else
|
||||
#include "WProgram.h" /* This is where the standard Arduino code lies */
|
||||
#endif
|
||||
#else
|
||||
#include <stdlib.h>
|
||||
#include <stdio.h>
|
||||
#ifdef __AVR__
|
||||
#include <avr/io.h>
|
||||
#include <avr/pgmspace.h>
|
||||
#endif
|
||||
#include <math.h>
|
||||
#include "defs.h"
|
||||
#include "types.h"
|
||||
#endif
|
||||
|
||||
// Define this to use reciprocal multiplication for division and some more speedups that might decrease precision
|
||||
//#define FFT_SPEED_OVER_PRECISION
|
||||
|
||||
// Define this to use a low-precision square root approximation instead of the regular sqrt() call
|
||||
// This might only work for specific use cases, but is significantly faster. Only works for ArduinoFFT<float>.
|
||||
//#define FFT_SQRT_APPROXIMATION
|
||||
|
||||
#ifdef FFT_SQRT_APPROXIMATION
|
||||
#include <type_traits>
|
||||
#else
|
||||
#define sqrt_internal sqrtf
|
||||
#endif
|
||||
|
||||
enum class FFTDirection
|
||||
{
|
||||
Reverse,
|
||||
Forward
|
||||
};
|
||||
|
||||
enum class FFTWindow
|
||||
{
|
||||
Rectangle, // rectangle (Box car)
|
||||
Hamming, // hamming
|
||||
Hann, // hann
|
||||
Triangle, // triangle (Bartlett)
|
||||
Nuttall, // nuttall
|
||||
Blackman, //blackman
|
||||
Blackman_Nuttall, // blackman nuttall
|
||||
Blackman_Harris, // blackman harris
|
||||
Flat_top, // flat top
|
||||
Welch // welch
|
||||
};
|
||||
|
||||
template <typename T>
|
||||
class ArduinoFFT
|
||||
{
|
||||
public:
|
||||
// Constructor
|
||||
ArduinoFFT(T *vReal, T *vImag, uint_fast16_t samples, T samplingFrequency, T *windowWeighingFactors = nullptr)
|
||||
: _vReal(vReal)
|
||||
, _vImag(vImag)
|
||||
, _samples(samples)
|
||||
#ifdef FFT_SPEED_OVER_PRECISION
|
||||
, _oneOverSamples(1.0 / samples)
|
||||
#endif
|
||||
, _samplingFrequency(samplingFrequency)
|
||||
, _windowWeighingFactors(windowWeighingFactors)
|
||||
{
|
||||
// Calculates the base 2 logarithm of sample count
|
||||
_power = 0;
|
||||
while (((samples >> _power) & 1) != 1)
|
||||
{
|
||||
_power++;
|
||||
}
|
||||
}
|
||||
|
||||
// Destructor
|
||||
~ArduinoFFT()
|
||||
{
|
||||
}
|
||||
|
||||
// Get library revision
|
||||
static uint8_t revision()
|
||||
{
|
||||
return 0x19;
|
||||
}
|
||||
|
||||
// Replace the data array pointers
|
||||
void setArrays(T *vReal, T *vImag)
|
||||
{
|
||||
_vReal = vReal;
|
||||
_vImag = vImag;
|
||||
}
|
||||
|
||||
// Computes in-place complex-to-complex FFT
|
||||
void compute(FFTDirection dir) const
|
||||
{
|
||||
// Reverse bits /
|
||||
uint_fast16_t j = 0;
|
||||
for (uint_fast16_t i = 0; i < (this->_samples - 1); i++)
|
||||
{
|
||||
if (i < j)
|
||||
{
|
||||
Swap(this->_vReal[i], this->_vReal[j]);
|
||||
if (dir == FFTDirection::Reverse)
|
||||
{
|
||||
Swap(this->_vImag[i], this->_vImag[j]);
|
||||
}
|
||||
}
|
||||
uint_fast16_t k = (this->_samples >> 1);
|
||||
while (k <= j)
|
||||
{
|
||||
j -= k;
|
||||
k >>= 1;
|
||||
}
|
||||
j += k;
|
||||
}
|
||||
// Compute the FFT
|
||||
#ifdef __AVR__
|
||||
uint_fast8_t index = 0;
|
||||
#endif
|
||||
T c1 = -1.0;
|
||||
T c2 = 0.0;
|
||||
uint_fast16_t l2 = 1;
|
||||
for (uint_fast8_t l = 0; (l < this->_power); l++)
|
||||
{
|
||||
uint_fast16_t l1 = l2;
|
||||
l2 <<= 1;
|
||||
T u1 = 1.0;
|
||||
T u2 = 0.0;
|
||||
for (j = 0; j < l1; j++)
|
||||
{
|
||||
for (uint_fast16_t i = j; i < this->_samples; i += l2)
|
||||
{
|
||||
uint_fast16_t i1 = i + l1;
|
||||
T t1 = u1 * this->_vReal[i1] - u2 * this->_vImag[i1];
|
||||
T t2 = u1 * this->_vImag[i1] + u2 * this->_vReal[i1];
|
||||
this->_vReal[i1] = this->_vReal[i] - t1;
|
||||
this->_vImag[i1] = this->_vImag[i] - t2;
|
||||
this->_vReal[i] += t1;
|
||||
this->_vImag[i] += t2;
|
||||
}
|
||||
T z = ((u1 * c1) - (u2 * c2));
|
||||
u2 = ((u1 * c2) + (u2 * c1));
|
||||
u1 = z;
|
||||
}
|
||||
#ifdef __AVR__
|
||||
c2 = pgm_read_float_near(&(_c2[index]));
|
||||
c1 = pgm_read_float_near(&(_c1[index]));
|
||||
index++;
|
||||
#else
|
||||
T cTemp = 0.5 * c1;
|
||||
c2 = sqrt_internal(0.5 - cTemp);
|
||||
c1 = sqrt_internal(0.5 + cTemp);
|
||||
#endif
|
||||
c2 = dir == FFTDirection::Forward ? -c2 : c2;
|
||||
}
|
||||
// Scaling for reverse transform
|
||||
if (dir != FFTDirection::Forward)
|
||||
{
|
||||
for (uint_fast16_t i = 0; i < this->_samples; i++)
|
||||
{
|
||||
#ifdef FFT_SPEED_OVER_PRECISION
|
||||
this->_vReal[i] *= _oneOverSamples;
|
||||
this->_vImag[i] *= _oneOverSamples;
|
||||
#else
|
||||
this->_vReal[i] /= this->_samples;
|
||||
this->_vImag[i] /= this->_samples;
|
||||
#endif
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void complexToMagnitude() const
|
||||
{
|
||||
// vM is half the size of vReal and vImag
|
||||
for (uint_fast16_t i = 0; i < this->_samples; i++)
|
||||
{
|
||||
this->_vReal[i] = sqrt_internal(sq(this->_vReal[i]) + sq(this->_vImag[i]));
|
||||
}
|
||||
}
|
||||
|
||||
void dcRemoval() const
|
||||
{
|
||||
// calculate the mean of vData
|
||||
T mean = 0;
|
||||
for (uint_fast16_t i = 1; i < ((this->_samples >> 1) + 1); i++)
|
||||
{
|
||||
mean += this->_vReal[i];
|
||||
}
|
||||
mean /= this->_samples;
|
||||
// Subtract the mean from vData
|
||||
for (uint_fast16_t i = 1; i < ((this->_samples >> 1) + 1); i++)
|
||||
{
|
||||
this->_vReal[i] -= mean;
|
||||
}
|
||||
}
|
||||
|
||||
void windowing(FFTWindow windowType, FFTDirection dir, bool withCompensation = false)
|
||||
{
|
||||
// check if values are already pre-computed for the correct window type and compensation
|
||||
if (_windowWeighingFactors && _weighingFactorsComputed &&
|
||||
_weighingFactorsFFTWindow == windowType &&
|
||||
_weighingFactorsWithCompensation == withCompensation)
|
||||
{
|
||||
// yes. values are precomputed
|
||||
if (dir == FFTDirection::Forward)
|
||||
{
|
||||
for (uint_fast16_t i = 0; i < (this->_samples >> 1); i++)
|
||||
{
|
||||
this->_vReal[i] *= _windowWeighingFactors[i];
|
||||
this->_vReal[this->_samples - (i + 1)] *= _windowWeighingFactors[i];
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
for (uint_fast16_t i = 0; i < (this->_samples >> 1); i++)
|
||||
{
|
||||
#ifdef FFT_SPEED_OVER_PRECISION
|
||||
// on many architectures reciprocals and multiplying are much faster than division
|
||||
T oneOverFactor = 1.0 / _windowWeighingFactors[i];
|
||||
this->_vReal[i] *= oneOverFactor;
|
||||
this->_vReal[this->_samples - (i + 1)] *= oneOverFactor;
|
||||
#else
|
||||
this->_vReal[i] /= _windowWeighingFactors[i];
|
||||
this->_vReal[this->_samples - (i + 1)] /= _windowWeighingFactors[i];
|
||||
#endif
|
||||
}
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
// no. values need to be pre-computed or applied
|
||||
T samplesMinusOne = (T(this->_samples) - 1.0);
|
||||
T compensationFactor = _WindowCompensationFactors[static_cast<uint_fast8_t>(windowType)];
|
||||
for (uint_fast16_t i = 0; i < (this->_samples >> 1); i++)
|
||||
{
|
||||
T indexMinusOne = T(i);
|
||||
T ratio = (indexMinusOne / samplesMinusOne);
|
||||
T weighingFactor = 1.0;
|
||||
// Compute and record weighting factor
|
||||
switch (windowType)
|
||||
{
|
||||
case FFTWindow::Rectangle: // rectangle (box car)
|
||||
weighingFactor = 1.0;
|
||||
break;
|
||||
case FFTWindow::Hamming: // hamming
|
||||
weighingFactor = 0.54 - (0.46 * cos(TWO_PI * ratio));
|
||||
break;
|
||||
case FFTWindow::Hann: // hann
|
||||
weighingFactor = 0.54 * (1.0 - cos(TWO_PI * ratio));
|
||||
break;
|
||||
case FFTWindow::Triangle: // triangle (Bartlett)
|
||||
weighingFactor = 1.0 - ((2.0 * abs(indexMinusOne - (samplesMinusOne / 2.0))) / samplesMinusOne);
|
||||
break;
|
||||
case FFTWindow::Nuttall: // nuttall
|
||||
weighingFactor = 0.355768 - (0.487396 * (cos(TWO_PI * ratio))) + (0.144232 * (cos(FOUR_PI * ratio))) - (0.012604 * (cos(SIX_PI * ratio)));
|
||||
break;
|
||||
case FFTWindow::Blackman: // blackman
|
||||
weighingFactor = 0.42323 - (0.49755 * (cos(TWO_PI * ratio))) + (0.07922 * (cos(FOUR_PI * ratio)));
|
||||
break;
|
||||
case FFTWindow::Blackman_Nuttall: // blackman nuttall
|
||||
weighingFactor = 0.3635819 - (0.4891775 * (cos(TWO_PI * ratio))) + (0.1365995 * (cos(FOUR_PI * ratio))) - (0.0106411 * (cos(SIX_PI * ratio)));
|
||||
break;
|
||||
case FFTWindow::Blackman_Harris: // blackman harris
|
||||
weighingFactor = 0.35875 - (0.48829 * (cos(TWO_PI * ratio))) + (0.14128 * (cos(FOUR_PI * ratio))) - (0.01168 * (cos(SIX_PI * ratio)));
|
||||
break;
|
||||
case FFTWindow::Flat_top: // flat top
|
||||
weighingFactor = 0.2810639 - (0.5208972 * cos(TWO_PI * ratio)) + (0.1980399 * cos(FOUR_PI * ratio));
|
||||
break;
|
||||
case FFTWindow::Welch: // welch
|
||||
weighingFactor = 1.0 - sq((indexMinusOne - samplesMinusOne / 2.0) / (samplesMinusOne / 2.0));
|
||||
break;
|
||||
}
|
||||
if (withCompensation)
|
||||
{
|
||||
weighingFactor *= compensationFactor;
|
||||
}
|
||||
if (_windowWeighingFactors)
|
||||
{
|
||||
_windowWeighingFactors[i] = weighingFactor;
|
||||
}
|
||||
if (dir == FFTDirection::Forward)
|
||||
{
|
||||
this->_vReal[i] *= weighingFactor;
|
||||
this->_vReal[this->_samples - (i + 1)] *= weighingFactor;
|
||||
}
|
||||
else
|
||||
{
|
||||
#ifdef FFT_SPEED_OVER_PRECISION
|
||||
// on many architectures reciprocals and multiplying are much faster than division
|
||||
T oneOverFactor = 1.0 / weighingFactor;
|
||||
this->_vReal[i] *= oneOverFactor;
|
||||
this->_vReal[this->_samples - (i + 1)] *= oneOverFactor;
|
||||
#else
|
||||
this->_vReal[i] /= weighingFactor;
|
||||
this->_vReal[this->_samples - (i + 1)] /= weighingFactor;
|
||||
#endif
|
||||
}
|
||||
}
|
||||
// mark cached values as pre-computed
|
||||
_weighingFactorsFFTWindow = windowType;
|
||||
_weighingFactorsWithCompensation = withCompensation;
|
||||
_weighingFactorsComputed = true;
|
||||
}
|
||||
}
|
||||
|
||||
T majorPeak() const
|
||||
{
|
||||
T maxY = 0;
|
||||
uint_fast16_t IndexOfMaxY = 0;
|
||||
//If sampling_frequency = 2 * max_frequency in signal,
|
||||
//value would be stored at position samples/2
|
||||
for (uint_fast16_t i = 1; i < ((this->_samples >> 1) + 1); i++)
|
||||
{
|
||||
if ((this->_vReal[i - 1] < this->_vReal[i]) && (this->_vReal[i] > this->_vReal[i + 1]))
|
||||
{
|
||||
if (this->_vReal[i] > maxY)
|
||||
{
|
||||
maxY = this->_vReal[i];
|
||||
IndexOfMaxY = i;
|
||||
}
|
||||
}
|
||||
}
|
||||
T delta = 0.5 * ((this->_vReal[IndexOfMaxY - 1] - this->_vReal[IndexOfMaxY + 1]) / (this->_vReal[IndexOfMaxY - 1] - (2.0 * this->_vReal[IndexOfMaxY]) + this->_vReal[IndexOfMaxY + 1]));
|
||||
T interpolatedX = ((IndexOfMaxY + delta) * this->_samplingFrequency) / (this->_samples - 1);
|
||||
if (IndexOfMaxY == (this->_samples >> 1))
|
||||
{
|
||||
//To improve calculation on edge values
|
||||
interpolatedX = ((IndexOfMaxY + delta) * this->_samplingFrequency) / (this->_samples);
|
||||
}
|
||||
// returned value: interpolated frequency peak apex
|
||||
return interpolatedX;
|
||||
}
|
||||
|
||||
void majorPeak(T &frequency, T &value) const
|
||||
{
|
||||
T maxY = 0;
|
||||
uint_fast16_t IndexOfMaxY = 0;
|
||||
//If sampling_frequency = 2 * max_frequency in signal,
|
||||
//value would be stored at position samples/2
|
||||
for (uint_fast16_t i = 1; i < ((this->_samples >> 1) + 1); i++)
|
||||
{
|
||||
if ((this->_vReal[i - 1] < this->_vReal[i]) && (this->_vReal[i] > this->_vReal[i + 1]))
|
||||
{
|
||||
if (this->_vReal[i] > maxY)
|
||||
{
|
||||
maxY = this->_vReal[i];
|
||||
IndexOfMaxY = i;
|
||||
}
|
||||
}
|
||||
}
|
||||
T delta = 0.5 * ((this->_vReal[IndexOfMaxY - 1] - this->_vReal[IndexOfMaxY + 1]) / (this->_vReal[IndexOfMaxY - 1] - (2.0 * this->_vReal[IndexOfMaxY]) + this->_vReal[IndexOfMaxY + 1]));
|
||||
T interpolatedX = ((IndexOfMaxY + delta) * this->_samplingFrequency) / (this->_samples - 1);
|
||||
if (IndexOfMaxY == (this->_samples >> 1))
|
||||
{
|
||||
//To improve calculation on edge values
|
||||
interpolatedX = ((IndexOfMaxY + delta) * this->_samplingFrequency) / (this->_samples);
|
||||
}
|
||||
// returned value: interpolated frequency peak apex
|
||||
frequency = interpolatedX;
|
||||
value = abs(this->_vReal[IndexOfMaxY - 1] - (2.0 * this->_vReal[IndexOfMaxY]) + this->_vReal[IndexOfMaxY + 1]);
|
||||
}
|
||||
|
||||
private:
|
||||
#ifdef __AVR__
|
||||
static const float _c1[] PROGMEM;
|
||||
static const float _c2[] PROGMEM;
|
||||
#endif
|
||||
static const T _WindowCompensationFactors[10];
|
||||
|
||||
// Mathematial constants
|
||||
#ifndef TWO_PI
|
||||
static constexpr T TWO_PI = 6.28318531; // might already be defined in Arduino.h
|
||||
#endif
|
||||
static constexpr T FOUR_PI = 12.56637061;
|
||||
static constexpr T SIX_PI = 18.84955593;
|
||||
|
||||
static inline void Swap(T &x, T &y)
|
||||
{
|
||||
T temp = x;
|
||||
x = y;
|
||||
y = temp;
|
||||
}
|
||||
|
||||
#ifdef FFT_SQRT_APPROXIMATION
|
||||
// Fast inverse square root aka "Quake 3 fast inverse square root", multiplied by x.
|
||||
// Uses one iteration of Halley's method for precision.
|
||||
// See: https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Iterative_methods_for_reciprocal_square_roots
|
||||
// And: https://github.com/HorstBaerbel/approx
|
||||
template <typename V = T>
|
||||
static inline V sqrt_internal(typename std::enable_if<std::is_same<V, float>::value, V>::type x)
|
||||
{
|
||||
union // get bits for float value
|
||||
{
|
||||
float x;
|
||||
int32_t i;
|
||||
} u;
|
||||
u.x = x;
|
||||
u.i = 0x5f375a86 - (u.i >> 1); // gives initial guess y0.
|
||||
float xu = x * u.x;
|
||||
float xu2 = xu * u.x;
|
||||
u.x = (0.125 * 3.0) * xu * (5.0 - xu2 * ((10.0 / 3.0) - xu2)); // Halley's method, repeating increases accuracy
|
||||
return u.x;
|
||||
}
|
||||
|
||||
template <typename V = T>
|
||||
static inline V sqrt_internal(typename std::enable_if<std::is_same<V, double>::value, V>::type x)
|
||||
{
|
||||
// According to HosrtBaerbel, on the ESP32 the approximation is not faster, so we use the standard function
|
||||
#ifdef ESP32
|
||||
return sqrt(x);
|
||||
#else
|
||||
union // get bits for float value
|
||||
{
|
||||
double x;
|
||||
int64_t i;
|
||||
} u;
|
||||
u.x = x;
|
||||
u.i = 0x5fe6ec85e7de30da - (u.i >> 1); // gives initial guess y0.
|
||||
double xu = x * u.x;
|
||||
double xu2 = xu * u.x;
|
||||
u.x = (0.125 * 3.0) * xu * (5.0 - xu2 * ((10.0 / 3.0) - xu2)); // Halley's method, repeating increases accuracy
|
||||
return u.x;
|
||||
#endif
|
||||
}
|
||||
#endif
|
||||
|
||||
/* Variables */
|
||||
T *_vReal = nullptr;
|
||||
T *_vImag = nullptr;
|
||||
uint_fast16_t _samples = 0;
|
||||
#ifdef FFT_SPEED_OVER_PRECISION
|
||||
T _oneOverSamples = 0.0;
|
||||
#endif
|
||||
T _samplingFrequency = 0;
|
||||
T *_windowWeighingFactors = nullptr;
|
||||
FFTWindow _weighingFactorsFFTWindow;
|
||||
bool _weighingFactorsWithCompensation = false;
|
||||
bool _weighingFactorsComputed = false;
|
||||
uint_fast8_t _power = 0;
|
||||
};
|
||||
|
||||
#ifdef __AVR__
|
||||
template <typename T>
|
||||
const float ArduinoFFT<T>::_c1[] PROGMEM = {
|
||||
0.0000000000, 0.7071067812, 0.9238795325, 0.9807852804,
|
||||
0.9951847267, 0.9987954562, 0.9996988187, 0.9999247018,
|
||||
0.9999811753, 0.9999952938, 0.9999988235, 0.9999997059,
|
||||
0.9999999265, 0.9999999816, 0.9999999954, 0.9999999989,
|
||||
0.9999999997};
|
||||
|
||||
template <typename T>
|
||||
const float ArduinoFFT<T>::_c2[] PROGMEM = {
|
||||
1.0000000000, 0.7071067812, 0.3826834324, 0.1950903220,
|
||||
0.0980171403, 0.0490676743, 0.0245412285, 0.0122715383,
|
||||
0.0061358846, 0.0030679568, 0.0015339802, 0.0007669903,
|
||||
0.0003834952, 0.0001917476, 0.0000958738, 0.0000479369,
|
||||
0.0000239684};
|
||||
#endif
|
||||
|
||||
template <typename T>
|
||||
const T ArduinoFFT<T>::_WindowCompensationFactors[10] = {
|
||||
1.0000000000 * 2.0, // rectangle (Box car)
|
||||
1.8549343278 * 2.0, // hamming
|
||||
1.8554726898 * 2.0, // hann
|
||||
2.0039186079 * 2.0, // triangle (Bartlett)
|
||||
2.8163172034 * 2.0, // nuttall
|
||||
2.3673474360 * 2.0, // blackman
|
||||
2.7557840395 * 2.0, // blackman nuttall
|
||||
2.7929062517 * 2.0, // blackman harris
|
||||
3.5659039231 * 2.0, // flat top
|
||||
1.5029392863 * 2.0 // welch
|
||||
};
|
||||
|
||||
#endif
|
@ -1,90 +0,0 @@
|
||||
/*! \file avrlibdefs.h \brief AVRlib global defines and macros. */
|
||||
//*****************************************************************************
|
||||
//
|
||||
// File Name : 'avrlibdefs.h'
|
||||
// Title : AVRlib global defines and macros include file
|
||||
// Author : Pascal Stang
|
||||
// Created : 7/12/2001
|
||||
// Revised : 9/30/2002
|
||||
// Version : 1.1
|
||||
// Target MCU : Atmel AVR series
|
||||
// Editor Tabs : 4
|
||||
//
|
||||
// Description : This include file is designed to contain items useful to all
|
||||
// code files and projects, regardless of specific implementation.
|
||||
//
|
||||
// This code is distributed under the GNU Public License
|
||||
// which can be found at http://www.gnu.org/licenses/gpl.txt
|
||||
//
|
||||
//*****************************************************************************
|
||||
|
||||
|
||||
#ifndef AVRLIBDEFS_H
|
||||
#define AVRLIBDEFS_H
|
||||
|
||||
//#define F_CPU 4000000
|
||||
#define MEM_TYPE 1
|
||||
|
||||
// Code compatibility to new AVR-libc
|
||||
// outb(), inb(), inw(), outw(), BV(), sbi(), cbi(), sei(), cli()
|
||||
#ifndef outb
|
||||
#define outb(addr, data) addr = (data)
|
||||
#endif
|
||||
#ifndef inb
|
||||
#define inb(addr) (addr)
|
||||
#endif
|
||||
#ifndef outw
|
||||
#define outw(addr, data) addr = (data)
|
||||
#endif
|
||||
#ifndef inw
|
||||
#define inw(addr) (addr)
|
||||
#endif
|
||||
#ifndef BV
|
||||
#define BV(bit) (1<<(bit))
|
||||
#endif
|
||||
//#ifndef cbi
|
||||
// #define cbi(reg,bit) reg &= ~(BV(bit))
|
||||
//#endif
|
||||
//#ifndef sbi
|
||||
// #define sbi(reg,bit) reg |= (BV(bit))
|
||||
//#endif
|
||||
#ifndef cli
|
||||
#define cli() __asm__ __volatile__ ("cli" ::)
|
||||
#endif
|
||||
#ifndef sei
|
||||
#define sei() __asm__ __volatile__ ("sei" ::)
|
||||
#endif
|
||||
|
||||
// support for individual port pin naming in the mega128
|
||||
// see port128.h for details
|
||||
#ifdef __AVR_ATmega128__
|
||||
// not currently necessary due to inclusion
|
||||
// of these defines in newest AVR-GCC
|
||||
// do a quick test to see if include is needed
|
||||
#ifndef PD0
|
||||
//#include "port128.h"
|
||||
#endif
|
||||
#endif
|
||||
|
||||
// use this for packed structures
|
||||
// (this is seldom necessary on an 8-bit architecture like AVR,
|
||||
// but can assist in code portability to AVR)
|
||||
#define GNUC_PACKED __attribute__((packed))
|
||||
|
||||
// port address helpers
|
||||
#define DDR(x) ((x)-1) // address of data direction register of port x
|
||||
#define PIN(x) ((x)-2) // address of input register of port x
|
||||
|
||||
// MIN/MAX/ABS macros
|
||||
#define MIN(a,b) ((a<b)?(a):(b))
|
||||
#define MAX(a,b) ((a>b)?(a):(b))
|
||||
#define ABS(x) ((x>0)?(x):(-x))
|
||||
|
||||
// constants
|
||||
#define PI 3.14159265359
|
||||
|
||||
//Math
|
||||
#define sq(x) ((x)*(x))
|
||||
#define constrain(amt,low,high) ((amt)<(low)?(low):((amt)>(high)?(high):(amt)))
|
||||
|
||||
#endif
|
@ -1,69 +0,0 @@
|
||||
//useful things to include in code
|
||||
|
||||
#ifndef TYPES_H
|
||||
#define TYPES_H
|
||||
|
||||
#ifndef WIN32
|
||||
// true/false defines
|
||||
#define FALSE 0
|
||||
#define TRUE -1
|
||||
#endif
|
||||
|
||||
// datatype definitions macros
|
||||
typedef unsigned char u08;
|
||||
typedef signed char s08;
|
||||
typedef unsigned short u16;
|
||||
typedef signed short s16;
|
||||
typedef unsigned long u32;
|
||||
typedef signed long s32;
|
||||
typedef unsigned long long u64;
|
||||
typedef signed long long s64;
|
||||
|
||||
// #ifndef __AVR__
|
||||
#ifdef __MBED__
|
||||
// use inttypes.h instead
|
||||
// C99 standard integer type definitions
|
||||
typedef unsigned char uint8_t;
|
||||
typedef signed char int8_t;
|
||||
typedef unsigned short uint16_t;
|
||||
typedef signed short int16_t;
|
||||
/*typedef unsigned long uint32_t;
|
||||
typedef signed long int32_t;
|
||||
typedef unsigned long uint64_t;
|
||||
typedef signed long int64_t;
|
||||
*/
|
||||
#endif
|
||||
|
||||
// maximum value that can be held
|
||||
// by unsigned data types (8,16,32bits)
|
||||
#define MAX_U08 255
|
||||
#define MAX_U16 65535
|
||||
#define MAX_U32 4294967295
|
||||
|
||||
// maximum values that can be held
|
||||
// by signed data types (8,16,32bits)
|
||||
#define MIN_S08 -128
|
||||
#define MAX_S08 127
|
||||
#define MIN_S16 -32768
|
||||
#define MAX_S16 32767
|
||||
#define MIN_S32 -2147483648
|
||||
#define MAX_S32 2147483647
|
||||
|
||||
#ifndef WIN32
|
||||
// more type redefinitions
|
||||
typedef unsigned char BOOL;
|
||||
typedef unsigned char BYTE;
|
||||
typedef unsigned int WORD;
|
||||
typedef unsigned long DWORD;
|
||||
|
||||
typedef unsigned char UCHAR;
|
||||
typedef unsigned int UINT;
|
||||
typedef unsigned short USHORT;
|
||||
typedef unsigned long ULONG;
|
||||
|
||||
typedef char CHAR;
|
||||
typedef int INT;
|
||||
typedef long LONG;
|
||||
#endif
|
||||
|
||||
#endif
|
Loading…
Reference in New Issue
Block a user