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| #include <Adafruit\_NeoPixel.h>
#include <math.h>
#define N\_PIXELS 24 // WS2812像素个数
#define MIC\_PIN A0 // 麦克风采样引脚
#define LEFT\_STRIP\_PIN 3 // WS2812引脚
#define RIGHT\_STRIP\_PIN 4 // WS2812引脚
#define SAMPLE\_WINDOW 10 // 平均水平的样本窗口
#define PEAK\_HANG 15 // 峰点下降前暂停时间
#define PEAK\_FALL 6 // 峰点下降率
#define INPUT\_FLOOR 40 // 模拟读取输入的较低范围 建议 40
#define INPUT\_CEILING 400 // analogRead 输入最大量程，值越小越灵敏(1023 = max) 建议 400
byte peak = 20; // 列的峰值水平； 用于下降的点
unsigned int sample;
byte dotCount = 0; // 峰值点帧计数器
byte dotHangCount = 0; // 用于保持峰值点的帧计数器
Adafruit_NeoPixel leftStrip = Adafruit\_NeoPixel(N_PIXELS, LEFT_STRIP_PIN, NEO_GRB + NEO_KHZ800);
Adafruit_NeoPixel rightStrip = Adafruit\_NeoPixel(N_PIXELS, RIGHT_STRIP_PIN, NEO_GRB + NEO_KHZ800);
volatile int state = LOW;
void setup() {
// 初始化灯带
leftStrip.begin();
leftStrip.show();
rightStrip.begin();
rightStrip.show();
}
void loop() {
VUmeter();
}
void VUmeter(){
unsigned long startMillis= millis(); // 样本窗口开始
float peakToPeak = 0;
unsigned int signalMax = 0;
unsigned int signalMin = 1023;
unsigned int c, y;
// 收集样本窗口长度的数据（以 mS 为单位）
while (millis() - startMillis < SAMPLE_WINDOW)
{
sample = analogRead(MIC_PIN);
if (sample < 1024) // 剔除虚假读数
{
if (sample > signalMax)
{
signalMax = sample; // 保存最大值
}
else if (sample < signalMin)
{
signalMin = sample; // 保存最小值
}
}
}
peakToPeak = signalMax - signalMin; // max - min = peak-peak 振幅
//用彩虹渐变填充
for (int i=0;i<=rightStrip.numPixels()-1;i++){
leftStrip.setPixelColor(i,Wheel(map(i,0,leftStrip.numPixels()-1,10,200)));
rightStrip.setPixelColor(i,Wheel(map(i,0,rightStrip.numPixels()-1,10,200)));
}
//以对数方式而不是线性方式缩放输入
c = fscale(INPUT_FLOOR, INPUT_CEILING, leftStrip.numPixels(), 0, peakToPeak, 2);
if(c < peak) {
peak = c; // 保持点在顶部
dotHangCount = 0; // 让点在落下之前挂起
}
if (c <= leftStrip.numPixels()) { // 用关闭像素填充部分列
drawLine(leftStrip.numPixels(), leftStrip.numPixels()-c, leftStrip.Color(0, 0, 0));
}
//设置峰值点以匹配彩虹渐变
y = leftStrip.numPixels() - peak;
leftStrip.setPixelColor(y-1,Wheel(map(y,0,leftStrip.numPixels()-1,10,200)));
rightStrip.setPixelColor(y-1,Wheel(map(y,0,rightStrip.numPixels()-1,10,200)));
leftStrip.show();
rightStrip.show();
// 基于帧的峰点动画
if(dotHangCount > PEAK_HANG) { //峰值停顿长度
if(++dotCount >= PEAK_FALL) { //跌落率
peak++;
dotCount = 0;
}
}
else {
dotHangCount++;
}
}
//用于在给定颜色的两点之间画一条线
void drawLine(uint8\_t from, uint8\_t to, uint32\_t c) {
uint8\_t fromTemp;
if (from > to) {
fromTemp = from;
from = to;
to = fromTemp;
}
for(int i=from; i<=to; i++){
leftStrip.setPixelColor(i, c);
rightStrip.setPixelColor(i, c);
}
}
// 缩放输入值
float fscale( float originalMin, float originalMax, float newBegin, float
newEnd, float inputValue, float curve){
float OriginalRange = 0;
float NewRange = 0;
float zeroRefCurVal = 0;
float normalizedCurVal = 0;
float rangedValue = 0;
boolean invFlag = 0;
// 条件曲线参数限制范围
if (curve > 10) curve = 10;
if (curve < -10) curve = -10;
// 反转和缩放 - 正数对输出的高端给予更多权重
curve = (curve \* -.1) ;
curve = pow(10, curve); // 将线性刻度转换为其他 pow 函数的对数指数
// 检查范围
if (inputValue < originalMin) {
inputValue = originalMin;
}
if (inputValue > originalMax) {
inputValue = originalMax;
}
OriginalRange = originalMax - originalMin;
if (newEnd > newBegin){
NewRange = newEnd - newBegin;
}
else
{
NewRange = newBegin - newEnd;
invFlag = 1;
}
zeroRefCurVal = inputValue - originalMin;
normalizedCurVal = zeroRefCurVal / OriginalRange; // 归一化
if (originalMin > originalMax ) {
return 0;
}
if (invFlag == 0){
rangedValue = (pow(normalizedCurVal, curve) \* NewRange) + newBegin;
}
else // 反转范围
{
rangedValue = newBegin - (pow(normalizedCurVal, curve) \* NewRange);
}
return rangedValue;
}
// 转换颜色
uint32\_t Wheel(byte WheelPos) {
if(WheelPos < 85) {
return leftStrip.Color(WheelPos \* 3, 255 - WheelPos \* 3, 0);
}
else if(WheelPos < 170) {
WheelPos -= 85;
return leftStrip.Color(255 - WheelPos \* 3, 0, WheelPos \* 3);
}
else {
WheelPos -= 170;
return leftStrip.Color(0, WheelPos \* 3, 255 - WheelPos \* 3);
}
}
|
