【花雕动手做】有趣好玩的音乐可视化系列小项目（21）--CD 光盘灯

偶然心血来潮，想要做一个音乐可视化的系列专题。这个专题的难度有点高，涉及面也比较广泛，相关的FFT和FHT等算法也相当复杂，不过还是打算从最简单的开始，实际动手做做试验，耐心尝试一下各种方案，逐步积累些有用的音乐频谱可视化的资料，也会争取成型一些实用好玩的音乐可视器项目。

找到几张报废的CD 光盘， 还有一只带盖的快餐盒子，尝试搭建一个新型CD 光盘音乐可视化灯。

快餐盒子

用热干胶，把光盘固定在餐盒之上…

声音模块，使用性价比更高的MAX4466声音传感器。

MAX4466
是微功率运算放大器，经过优化，可用作麦克风前置放大器。它们提供了优化的增益带宽产品与电源电流的理想组合，以及超小型封装中实现低电压工件环境。 MAX4466具有增益稳定特性，仅需24μA的电源电流即可提供200kHz的增益带宽。经过解压缩，可实现+5V/V的最小稳定增益，并提供600KHZ增益带宽。此外这些放大器具有轨到轨输出，高 AVOL ，以及出色的电源抑制和共模抑制比，适合在嘈杂环境中工作。广泛应用于蜂窝电话、数字复读装置、耳机、助听器、麦克风前置放大器、便携计算机和语音识别系统中。

MAX4466模块特点
电源电压：+2.4V至+5.5V（可直接接STM/ARDUNIO/树莓派等开发板）
电源抑制比：112dB
共模抑制比：126dB
AVOL：125dB（RL = 100kΩ) 轨到轨输出
静态电源电流：24μA
增益带宽：600kHz
尺寸：20.8mm x 13.8mm x 7.5mm/0.8 x 0.5 x 0.3inch

该模块在 Vcc 和接地引线上都包含铁氧体，以最大限度地减少电源噪声。如果与 MCU 一起使用，最好使用 2.4V – 5.5V 范围内可用的最安静的电源。在 Arduino 上，这通常是 3.3V 电源。输出是直流耦合的。当输出信号处于静止状态时，它将位于 Vcc/2。如果 Vcc 为 5V，则输出将为 2.5V。如果输出需要交流耦合，可以在输出引脚和它驱动的电路的输入之间增加一个100uF的电容。背面的小型单圈电位器可让您将增益从 25x 调整到 125x。逆时针旋转电位器会增加增益，而逆时针旋转会降低增益。

WS2812B灯带选用的是每米60灯黑底裸板

WS2812B其主要特点

智能反接保护，电源反接不会损坏IC。

IC控制电路与LED点光源公用一个电源。

控制电路与RGB芯片集成在一个5050封装的元器件中，构成一个完整的外控像素点。

内置信号整形电路，任何一个像素点收到信号后经过波形整形再输出，保证线路波形畸变不会累加。

内置上电复位和掉电复位电路。

每个像素点的三基色颜色可实现256级亮度显示，完成16777216种颜色的全真色彩显示，扫描频率不低于400Hz/s。

串行级联接口，能通过一根信号线完成数据的接收与解码。

任意两点传传输距离在不超过5米时无需增加任何电路。

当刷新速率30帧/秒时，级联数不小于1024点。

数据发送速度可达800Kbps。

光的颜色高度一致，性价比高。

主要应用领域

LED全彩发光字灯串,LED全彩模组， LED全彩软灯条硬灯条,LED护栏管。

LED点光源,LED像素屏,LED异形屏，各种电子产品，电器设备跑马灯。

安装灯带

【花雕动手做】有趣好玩的音乐可视化系列小项目（21）–CD 光盘灯
项目程序之一：LED循环绿色快闪测试

/*
  【花雕动手做】有趣好玩的音乐可视化系列小项目（21）--CD 光盘灯
  项目程序之一：LED循环绿色快闪测试
*/

#include 

#define PIN 6
#define MAX_LED 23

#define ADD true
#define SUB false

int val = 0;
boolean stat = ADD;

Adafruit_NeoPixel strip = Adafruit_NeoPixel( MAX_LED, PIN, NEO_RGB + NEO_KHZ800 );

void setup() {
  strip.begin();
  strip.show();
}

void loop() {
  uint8_t i, a = 0;
  uint32_t color = strip.Color(255, 0, 0);
  while (a < 24)
  {
    for (i = 0; i < 23; i++)
    {
      if (i == a) strip.setPixelColor(i, color);
      else strip.setPixelColor(i, 0);
    }
    strip.show();
    delay(100);
    a++;
  }
}

实验场景图

实验场景图 动态图

【花雕动手做】有趣好玩的音乐可视化系列小项目（21）–CD 光盘灯
项目程序之二：NeoPixel 灯条测试程序
模块接线：WS2812B接D6
MAX4466 UNO
VCC 5V
GND GND
OUT A0

/*
  【花雕动手做】有趣好玩的音乐可视化系列小项目（21）--CD 光盘灯
  项目程序之二：NeoPixel 灯条测试程序
  模块接线：WS2812B接D6
  MAX4466      UNO
  VCC          5V
  GND         GND
  OUT          A0
*/

#include 
#ifdef __AVR__
#include  // Required for 16 MHz Adafruit Trinket
#endif

// Which pin on the Arduino is connected to the NeoPixels?
// On a Trinket or Gemma we suggest changing this to 1:
#define LED_PIN    6

// How many NeoPixels are attached to the Arduino?
#define LED_COUNT 23

// Declare our NeoPixel strip object:
Adafruit_NeoPixel strip(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800);
// Argument 1 = Number of pixels in NeoPixel strip
// Argument 2 = Arduino pin number (most are valid)
// Argument 3 = Pixel type flags, add together as needed:
//   NEO_KHZ800  800 KHz bitstream (most NeoPixel products w/WS2812 LEDs)
//   NEO_KHZ400  400 KHz (classic 'v1' (not v2) FLORA pixels, WS2811 drivers)
//   NEO_GRB     Pixels are wired for GRB bitstream (most NeoPixel products)
//   NEO_RGB     Pixels are wired for RGB bitstream (v1 FLORA pixels, not v2)
//   NEO_RGBW    Pixels are wired for RGBW bitstream (NeoPixel RGBW products)


// setup() function -- runs once at startup --------------------------------

void setup() {
  // These lines are specifically to support the Adafruit Trinket 5V 16 MHz.
  // Any other board, you can remove this part (but no harm leaving it):
#if defined(__AVR_ATtiny85__) && (F_CPU == 16000000)
  clock_prescale_set(clock_div_1);
#endif
  // END of Trinket-specific code.

  strip.begin();           // INITIALIZE NeoPixel strip object (REQUIRED)
  strip.show();            // Turn OFF all pixels ASAP
  strip.setBrightness(150); // Set BRIGHTNESS to about 1/5 (max = 255)
}


// loop() function -- runs repeatedly as long as board is on ---------------

void loop() {
  // Fill along the length of the strip in various colors...
  colorWipe(strip.Color(255,   0,   0), 50); // Red
  colorWipe(strip.Color(  0, 255,   0), 50); // Green
  colorWipe(strip.Color(  0,   0, 255), 50); // Blue

  // Do a theater marquee effect in various colors...
  theaterChase(strip.Color(127, 127, 127), 50); // White, half brightness
  theaterChase(strip.Color(127,   0,   0), 50); // Red, half brightness
  theaterChase(strip.Color(  0,   0, 127), 50); // Blue, half brightness

  rainbow(10);             // Flowing rainbow cycle along the whole strip
  theaterChaseRainbow(50); // Rainbow-enhanced theaterChase variant
}


// Some functions of our own for creating animated effects -----------------

// Fill strip pixels one after another with a color. Strip is NOT cleared
// first; anything there will be covered pixel by pixel. Pass in color
// (as a single 'packed' 32-bit value, which you can get by calling
// strip.Color(red, green, blue) as shown in the loop() function above),
// and a delay time (in milliseconds) between pixels.
void colorWipe(uint32_t color, int wait) {
  for (int i = 0; i < strip.numPixels(); i++) { // For each pixel in strip...
    strip.setPixelColor(i, color);         //  Set pixel's color (in RAM)
    strip.show();                          //  Update strip to match
    delay(wait);                           //  Pause for a moment
  }
}

// Theater-marquee-style chasing lights. Pass in a color (32-bit value,
// a la strip.Color(r,g,b) as mentioned above), and a delay time (in ms)
// between frames.
void theaterChase(uint32_t color, int wait) {
  for (int a = 0; a < 10; a++) { // Repeat 10 times...
    for (int b = 0; b < 3; b++) { //  'b' counts from 0 to 2...
      strip.clear();         //   Set all pixels in RAM to 0 (off)
      // 'c' counts up from 'b' to end of strip in steps of 3...
      for (int c = b; c < strip.numPixels(); c += 3) {
        strip.setPixelColor(c, color); // Set pixel 'c' to value 'color'
      }
      strip.show(); // Update strip with new contents
      delay(wait);  // Pause for a moment
    }
  }
}

// Rainbow cycle along whole strip. Pass delay time (in ms) between frames.
void rainbow(int wait) {
  // Hue of first pixel runs 5 complete loops through the color wheel.
  // Color wheel has a range of 65536 but it's OK if we roll over, so
  // just count from 0 to 5*65536. Adding 256 to firstPixelHue each time
  // means we'll make 5*65536/256 = 1280 passes through this outer loop:
  for (long firstPixelHue = 0; firstPixelHue < 5 * 65536; firstPixelHue += 256) {
    for (int i = 0; i < strip.numPixels(); i++) { // For each pixel in strip...
      // Offset pixel hue by an amount to make one full revolution of the
      // color wheel (range of 65536) along the length of the strip
      // (strip.numPixels() steps):
      int pixelHue = firstPixelHue + (i * 65536L / strip.numPixels());
      // strip.ColorHSV() can take 1 or 3 arguments: a hue (0 to 65535) or
      // optionally add saturation and value (brightness) (each 0 to 255).
      // Here we're using just the single-argument hue variant. The result
      // is passed through strip.gamma32() to provide 'truer' colors
      // before assigning to each pixel:
      strip.setPixelColor(i, strip.gamma32(strip.ColorHSV(pixelHue)));
    }
    strip.show(); // Update strip with new contents
    delay(wait);  // Pause for a moment
  }
}

// Rainbow-enhanced theater marquee. Pass delay time (in ms) between frames.
void theaterChaseRainbow(int wait) {
  int firstPixelHue = 0;     // First pixel starts at red (hue 0)
  for (int a = 0; a < 30; a++) { // Repeat 30 times...
    for (int b = 0; b < 3; b++) { //  'b' counts from 0 to 2...
      strip.clear();         //   Set all pixels in RAM to 0 (off)
      // 'c' counts up from 'b' to end of strip in increments of 3...
      for (int c = b; c < strip.numPixels(); c += 3) {
        // hue of pixel 'c' is offset by an amount to make one full
        // revolution of the color wheel (range 65536) along the length
        // of the strip (strip.numPixels() steps):
        int      hue   = firstPixelHue + c * 65536L / strip.numPixels();
        uint32_t color = strip.gamma32(strip.ColorHSV(hue)); // hue -> RGB
        strip.setPixelColor(c, color); // Set pixel 'c' to value 'color'
      }
      strip.show();                // Update strip with new contents
      delay(wait);                 // Pause for a moment
      firstPixelHue += 65536 / 90; // One cycle of color wheel over 90 frames
    }
  }
}

实验场景图

实验的视频记录（1分05秒）

https://v.youku.com/v_show/id_XNTg5OTMzNTg3Mg==.html?spm=a2hcb.playlsit.page.3

【花雕动手做】有趣好玩的音乐可视化系列小项目（21）–CD 光盘灯
项目程序之三：音乐反应CD 光盘灯
模块接线：WS2812B接D6
MAX4466 UNO
VCC 5V
GND GND
OUT A0

/*
  【花雕动手做】有趣好玩的音乐可视化系列小项目（21）--CD 光盘灯
  项目程序之三：音乐反应CD 光盘灯
  模块接线：WS2812B接D6
  MAX4466      UNO
  VCC          5V
  GND         GND
  OUT          A0
*/

#include
#define LED_PIN 6
#define NUM_LEDS 23

CRGB leds[NUM_LEDS];
uint8_t hue = 0;
int soundsensor = A0;

void setup() {
  delay(2000);
  FastLED.addLeds<WS2812B, LED_PIN, GRB>(leds, NUM_LEDS);
  FastLED.setBrightness(155);
  pinMode(soundsensor, INPUT);
}

void loop() {
  int sensval = digitalRead(soundsensor);

  if (sensval == 1) {
    leds[0] = CRGB :: Red;
    fill_solid(leds, NUM_LEDS, CRGB :: Blue);
    rainbow_moving();
    FastLED.show();
    delay(10);
  }
  else {
    leds[0] = CRGB :: Black;
    fill_solid(leds, NUM_LEDS, CRGB :: Black);
    FastLED.show();
    delay(10);
  }
}

void rainbow_moving() {
  for (int i = 0; i < NUM_LEDS; i++) {
    leds[i] = CHSV(hue + (i * 10), 255, 255);
  }
  EVERY_N_MILLISECONDS(10) {
    hue++;
  }
}

实验的视频记录（4分27秒）

https://v.youku.com/v_show/id_XNTg5OTMwMjM4OA==.html?spm=a2hcb.playlsit.page.1

【花雕动手做】有趣好玩的音乐可视化系列小项目（21）–CD 光盘灯

项目程序之四：多彩MegunoLink音乐节拍灯

模块接线：WS2812B接D6

MAX4466 UNO

VCC 5V

GND GND

OUT A0

/*
  【花雕动手做】有趣好玩的音乐可视化系列小项目（21）--CD 光盘灯
  项目程序之四：多彩MegunoLink音乐节拍灯
  模块接线：WS2812B接D6
  MAX4466      UNO
  VCC          5V
  GND         GND
  OUT          A0
*/

#include
#include
#include

#define N_PIXELS  23
#define MIC_PIN   A0
#define LED_PIN   6
#define NOISE 10
#define TOP   (N_PIXELS+2)
#define LED_TYPE  WS2811
#define BRIGHTNESS  10
#define COLOR_ORDER GRB

CRGB leds[N_PIXELS];
int lvl = 0, minLvl = 0, maxLvl = 10;

ExponentialFilter<long> ADCFilter(5, 0);

void setup() {
  FastLED.addLeds<LED_TYPE, LED_PIN, COLOR_ORDER>(leds, N_PIXELS).setCorrection(TypicalLEDStrip);
  FastLED.setBrightness(BRIGHTNESS);
}

void loop() {
  int n, height;
  n = analogRead(MIC_PIN);
  n = abs(1023 - n);
  n = (n <= NOISE) ? 0 : abs(n - NOISE);
  ADCFilter.Filter(n);
  lvl = ADCFilter.Current();
  //  Serial.print(n);
  //  Serial.print(" ");
  //  Serial.println(lvl);
  height = TOP * (lvl - minLvl) / (long)(maxLvl - minLvl);
  if (height < 0L) height = 0;
  else if (height > TOP) height = TOP;
  for (uint8_t i = 0; i < N_PIXELS; i++) {
    if (i >= height) leds[i] = CRGB(0, 0, 0);
    else leds[i] = Wheel( map( i, 0, N_PIXELS - 1, 30, 150 ) );
  }
  FastLED.show();
}

CRGB Wheel(byte WheelPos) {
  if (WheelPos < 85)
    return CRGB(WheelPos * 3, 255 - WheelPos * 3, 0);
  else if (WheelPos < 170) {
    WheelPos -= 85;
    return CRGB(255 - WheelPos * 3, 0, WheelPos * 3);
  } else {
    WheelPos -= 170;
    return CRGB(0, WheelPos * 3, 255 - WheelPos * 3);
  }
}

实验的视频记录（4分36秒）

https://v.youku.com/v_show/id_XNTg5NzkzMzIzNg==.html?spm=a2hcb.playlsit.page.3

实验场景图 动态图

实验的视频记录（2分25秒）

https://v.youku.com/v_show/id_XNTg5ODA5NjYyNA==.html?spm=a2hcb.playlsit.page.1

实验的视频记录（1分10秒）

https://v.youku.com/v_show/id_XNTg5ODA5NjU3Ng==.html?spm=a2hcb.playlsit.page.3