/* ESP8266/32 Audio Spectrum Analyser on an SSD1306/SH1106 Display
* The MIT License (MIT) Copyright (c) 2017 by David Bird.
* The formulation and display of an AUdio Spectrum using an ESp8266 or ESP32 and SSD1306 or SH1106 OLED Display using a Fast Fourier Transform
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge,
* publish, distribute, but not to use it commercially for profit making or to sub-license and/or to sell copies of the Software or to
* permit persons to whom the Software is furnished to do so, subject to the following conditions:
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
* See more at http://dsbird.org.uk
*/
// Wio Audio Spectrum Display : 2020.05.28 macsbug
// https://macsbug.wordpress.com/2020/05/28/wio-audio-spectrum-display/
// GAIN ADJUST : GAIN UP = KEY_C(LEFT) , 5S_UP
// GAIN ADJUST : GAIN DOWN = KEY_B(RIGHT) , 5S_DOWN
// Audio Spectrum Display : 2017.12.31 macsbug
// https://macsbug.wordpress.com/2017/12/31/audio-spectrum-display-with-m5stack/
// https://github.com/tobozo/ESP32-8-Octave-Audio-Spectrum-Display/tree/wrover-kit
// https://github.com/G6EJD/ESP32-8266-Audio-Spectrum-Display
// https://github.com/kosme/arduinoFFT
// https://macsbug.wordpress.com/2017/12/31/audio-spectrum-display-with-m5stack/
#include "arduinoFFT.h"
arduinoFFT FFT = arduinoFFT();
#include <TFT_eSPI.h>
TFT_eSPI tft = TFT_eSPI();
#define SAMPLES 512 // Must be a power of 2
#define SAMPLING_FREQUENCY 40000
// Hz, must be 40000 or less due to ADC conversion time.
// Determines maximum frequency that can be analysed by the FFT Fmax=sampleF/2.
struct eqBand {
const char *freqname;
uint16_t amplitude;
int peak;
int lastpeak;
uint16_t lastval;
unsigned long lastmeasured;
};
eqBand audiospectrum[8] = {
//Adjust the amplitude values to fit your microphone
/*
{ "125Hz", 1000, 2, 0, 0, 0},
{ "250Hz", 500, 2, 0, 0, 0},
{ "500Hz", 300, 3, 0, 0, 0},
{ "1KHz", 250, 7, 0, 0, 0},
{ "2KHz", 200, 14, 0, 0, 0},
{ "4KHz", 100, 24, 0, 0, 0},
{ "8KHz", 50, 48, 0, 0, 0},
{ "16KHz", 25, 155, 0, 0, 0}
*/
{ "125Hz", 500, 0, 0, 0, 0},
{ "250Hz", 200, 0, 0, 0, 0},
{ "500Hz", 200, 0, 0, 0, 0},
{ "1KHz", 200, 0, 0, 0, 0},
{ "2KHz", 200, 0, 0, 0, 0},
{ "4KHz", 100, 0, 0, 0, 0},
{ "8KHz", 100, 0, 0, 0, 0},
{ "16KHz", 50, 0, 0, 0, 0}
};
unsigned int sampling_period_us;
unsigned long microseconds;
double vReal[SAMPLES];
double vImag[SAMPLES];
unsigned long newTime, oldTime;
uint16_t tft_width = 320;
uint16_t tft_height = 240;
uint8_t bands = 8;
uint8_t bands_width = floor( tft_width / bands );
uint8_t bands_pad = bands_width - 10;
uint16_t colormap[255]; // color palette for the band meter (pre-fill in setup)
int gain = 32;
void setup() {
tft.begin();
tft.setRotation(3);
tft.fillScreen(TFT_BLACK);
tft.setTextColor(TFT_YELLOW, TFT_BLACK);
tft.setTextSize(1);
pinMode(WIO_KEY_C, INPUT_PULLUP);// LEFT
pinMode(WIO_KEY_A, INPUT_PULLUP);// CENTER
pinMode(WIO_KEY_B, INPUT_PULLUP);// RIGHT
pinMode(WIO_5S_UP, INPUT_PULLUP);
pinMode(WIO_5S_DOWN, INPUT_PULLUP);
pinMode(WIO_5S_LEFT, INPUT_PULLUP);
pinMode(WIO_5S_RIGHT,INPUT_PULLUP);
pinMode(WIO_5S_PRESS,INPUT_PULLUP);
pinMode(WIO_MIC, INPUT);
sampling_period_us = round(1000000 * (1.0 / SAMPLING_FREQUENCY));
delay(2000);
for(uint8_t i=0;i<tft_height;i++) {
colormap[i] = tft.color565(tft_height-i*.5, i*1.1, 0);
}
for (byte band = 0; band <= 7; band++) {
tft.setCursor(bands_width*band + 2, 0);
tft.print(audiospectrum[band].freqname);
}
}
void loop() {
String cont = waitForcont();
if ((cont=="5UP") || (cont=="LEFT") ){gain++;tft.setCursor(5,10);tft.println(gain);}
if ((cont=="5DOWN") || (cont=="RIGHT")){gain--;tft.setCursor(5,10);tft.println(gain);}
for (int i = 0; i < SAMPLES; i++) {
newTime = micros()-oldTime;
oldTime = newTime;
vReal[i] = analogRead(WIO_MIC) * gain; // A conversion takes about 1uS on an ESP32
vImag[i] = 0;
while (micros() < (newTime + sampling_period_us)) {
// do nothing to wait
}
}
FFT.Windowing(vReal, SAMPLES, FFT_WIN_TYP_HAMMING, FFT_FORWARD);
FFT.Compute(vReal, vImag, SAMPLES, FFT_FORWARD);
FFT.ComplexToMagnitude(vReal, vImag, SAMPLES);
for (int i = 2; i < (SAMPLES/2); i++){
// Don't use sample 0 and only first SAMPLES/2 are usable.
// Each array eleement represents a frequency and its value the amplitude.
if (vReal[i] > 1500) { // Add a crude noise filter, 10 x amplitude or more
byte bandNum = getBand(i);
if(bandNum!=8) {
displayBand(bandNum, (int)vReal[i]/audiospectrum[bandNum].amplitude);
}
}
}
long vnow = millis();
for (byte band = 0; band <= 7; band++) {
// auto decay every 50ms on low activity bands
if(vnow - audiospectrum[band].lastmeasured > 50) {
displayBand(band, audiospectrum[band].lastval>4 ? audiospectrum[band].lastval-4 : 0);
}
if (audiospectrum[band].peak > 0) {
audiospectrum[band].peak -= 2;
if(audiospectrum[band].peak<=0) {
audiospectrum[band].peak = 0;
}
}
// only draw if peak changed
if(audiospectrum[band].lastpeak != audiospectrum[band].peak) {
// delete last peak
tft.drawFastHLine(bands_width*band,tft_height-audiospectrum[band].lastpeak,bands_pad,TFT_BLACK);
audiospectrum[band].lastpeak = audiospectrum[band].peak;
tft.drawFastHLine(bands_width*band, tft_height-audiospectrum[band].peak,
bands_pad, colormap[tft_height-audiospectrum[band].peak]);
}
}
}
void displayBand(int band, int dsize){
uint16_t hpos = bands_width*band;
int dmax = 200;
if(dsize>tft_height-10) {
dsize = tft_height-10; // leave some hspace for text
}
if(dsize < audiospectrum[band].lastval) {
// lower value, delete some lines
tft.fillRect(hpos, tft_height-audiospectrum[band].lastval,
bands_pad, audiospectrum[band].lastval - dsize, TFT_BLACK);
}
if (dsize > dmax) dsize = dmax;
for (int s = 0; s <= dsize; s=s+4){
tft.drawFastHLine(hpos,tft_height-s,bands_pad,colormap[tft_height-s]);
}
if (dsize > audiospectrum[band].peak) {
audiospectrum[band].peak = dsize;
}
audiospectrum[band].lastval = dsize;
audiospectrum[band].lastmeasured = millis();
}
byte getBand(int i) {
if (i<=2 ) return 0; // 125Hz
if (i >3 && i<=5 ) return 1; // 250Hz
if (i >5 && i<=7 ) return 2; // 500Hz
if (i >7 && i<=15 ) return 3; // 1000Hz
if (i >15 && i<=30 ) return 4; // 2000Hz
if (i >30 && i<=53 ) return 5; // 4000Hz
if (i >53 && i<=200 ) return 6; // 8000Hz
if (i >200 ) return 7; // 16000Hz
return 8;
}
String waitForcont() {
String cont = "";
if (digitalRead(WIO_KEY_A) ==LOW){cont="RIGHT" ;}else
if (digitalRead(WIO_KEY_B) ==LOW){cont="MIDDLE";}else
if (digitalRead(WIO_KEY_C) ==LOW){cont="LEFT" ;}else
if (digitalRead(WIO_5S_UP) ==LOW){cont="5UP" ;}else
if (digitalRead(WIO_5S_DOWN) ==LOW){cont="5DOWN" ;}else
if (digitalRead(WIO_5S_LEFT) ==LOW){cont="5LEFT" ;}else
if (digitalRead(WIO_5S_RIGHT)==LOW){cont="5RIGHT";}else
if (digitalRead(WIO_5S_PRESS)==LOW){cont="5CLICK";}else
if (cont != ""){return cont;}
}
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