flora-mic2color/flora-mic2color.ino

#include <Adafruit_NeoPixel.h>
#ifdef __AVR__
#include <avr/power.h>
#endif

#define NUMLEDS 1
#define LEDPIN 8
#define MICPIN A9
#define FAKEVCCPIN 6


Adafruit_NeoPixel strip = Adafruit_NeoPixel(NUMLEDS, LEDPIN, NEO_GRB + NEO_KHZ800);

#define BUFFSIZE 115
#define AVGSIZE 23

int rawBuff[BUFFSIZE];
int notHighBuff[BUFFSIZE];
int lowBuff[BUFFSIZE];
int index, minLow, maxLow, minMid, maxMid, minHigh, maxHigh;

#define RAWLOW(i) (lowBuff[i])
#define RAWMID(i) (notHighBuff[i]-lowBuff[i])
#define RAWHIGH(i) (rawBuff[i]-notHighBuff[i])

#define NORMLOW(i) constrain(map(RAWLOW(i), minLow, maxLow, 0, 255), 0, 255)
#define NORMMID(i) constrain(map(RAWMID(i), minMid, maxMid, 0, 255), 0, 255)
#define NORMHIGH(i) constrain(map(RAWHIGH(i), minHigh, maxHigh, 0, 255), 0, 255)

void setup() {
  pinMode(FAKEVCCPIN, OUTPUT);
  digitalWrite(FAKEVCCPIN, HIGH);
  index = 0;
  strip.begin();
  strip.show(); // Initialize all pixels to 'off'
  for (int i = 0; i < BUFFSIZE; i++) {
    rawBuff[i] = notHighBuff[i] = lowBuff[i] = 512;
  }
}

void loop() {
  rawBuff[index] = analogRead(MICPIN);
  notHighBuff[index] = 0;
  int nextIndex = (index + 1) % BUFFSIZE;
  for (int i = nextIndex + BUFFSIZE - AVGSIZE; i % BUFFSIZE != nextIndex; i++) {
    notHighBuff[index] += rawBuff[i % BUFFSIZE];
  }
  notHighBuff[index] /= AVGSIZE;
  lowBuff[index] = (notHighBuff[index] + notHighBuff[(index + BUFFSIZE - AVGSIZE) % BUFFSIZE]) / 2;
  minLow = minMid = minHigh = 1024;
  maxLow = maxMid = maxHigh = -1;
  for (int i = 0; i < BUFFSIZE; i++) {
    minLow =   min(minLow, RAWLOW(i));
    minMid =   min(minMid, RAWMID(i));
    minHigh =  min(minHigh, RAWHIGH(i));
    maxLow =   max(maxLow, RAWLOW(i));
    maxMid =   max(maxMid, RAWMID(i));
    maxHigh =  max(maxHigh, RAWHIGH(i));
  }
  strip.setPixelColor(0, strip.Color(NORMHIGH(index), NORMMID(index), NORMLOW(index)));
  strip.show();
  index = nextIndex;
};