Audio Reactive Visualizations

This example demonstrates various audio-reactive visualization modes using FastLED. It processes real-time audio input and creates stunning visual effects synchronized to music.

Features

Visualization Modes

1. Spectrum Bars - Classic frequency spectrum analyzer with vertical bars
2. Radial Spectrum - Circular frequency visualization radiating from center
3. Waveform - Real-time audio waveform display
4. VU Meter - Traditional volume unit meter with RMS and peak levels
5. Matrix Rain - Audio-reactive digital rain effect
6. Fire Effect - Flame simulation that responds to audio intensity
7. Plasma Wave - Animated plasma patterns modulated by audio

Audio Processing

• Real-time FFT Analysis - Frequency spectrum analysis
• Beat Detection - Automatic beat detection with adjustable sensitivity
• Auto Gain Control - Automatically adjusts to varying audio levels
• Noise Floor Filtering - Removes background noise
• Peak Detection - Tracks audio peaks with smoothing

Visual Controls

• 7 Color Palettes - Rainbow, Heat, Ocean, Forest, Party, Lava, Cloud
• Brightness Control - Adjustable LED brightness
• Fade Speed - Control trail/persistence effects
• Mirror Mode - Create symmetrical displays
• Beat Flash - Visual feedback on beat detection

Hardware Requirements

• Controller: ESP32, Teensy, or other platform with sufficient memory
• LED Matrix: 100x100 pixels (10,000 LEDs total)
• Memory: Requires SKETCH_HAS_LOTS_OF_MEMORY (not suitable for Arduino UNO)
• Audio Input: Microphone or line-in audio source

Wiring

LED Matrix:
- Data Pin: GPIO 3 (configurable via LED_PIN)
- Power: 5V (ensure adequate power supply for 10,000 LEDs!)
- Ground: Common ground with controller

Audio Input:
- Follow your platform's audio input configuration

Configuration

Display Settings

#define WIDTH 100          // Matrix width
#define HEIGHT 100         // Matrix height
#define LED_PIN 3          // Data pin for LEDs
#define LED_TYPE WS2812B   // LED chipset
#define COLOR_ORDER GRB    // Color order

Audio Settings

#define SAMPLE_RATE 44100  // Audio sample rate
#define FFT_SIZE 512       // FFT size for frequency analysis

UI Controls

Master Controls

• Enable Audio - Toggle audio processing on/off
• Visualization Mode - Select from 7 different modes

Audio Controls

• Audio Gain - Manual gain adjustment (0.1 - 5.0)
• Noise Floor - Background noise threshold (0.0 - 1.0)
• Auto Gain - Enable automatic gain control

Visual Controls

• Brightness - LED brightness (0 - 255)
• Fade Speed - Trail effect speed (0 - 255)
• Color Palette - Choose color scheme
• Mirror Mode - Enable symmetrical display

Beat Detection

• Beat Detection - Enable/disable beat detection
• Beat Sensitivity - Adjust detection threshold (0.5 - 3.0)
• Beat Flash - Enable visual flash on beats

Usage

1. Upload the sketch to your controller
2. Connect your LED matrix
3. Provide audio input (microphone or line-in)
4. Use the web UI to control visualizations
5. Select different modes and adjust parameters in real-time

Performance Tips

• This example requires significant processing power
• Reduce matrix size if experiencing lag
• Disable beat detection for lower CPU usage
• Use simpler visualization modes on slower processors

Customization

Adding New Visualizations

1. Add your mode name to the visualMode dropdown
2. Create a new drawYourMode() function
3. Add a case in the main switch statement
4. Implement your visualization logic

Modifying Color Palettes

Edit the getCurrentPalette() function to add custom palettes:

case 7: return YourCustomPalette_p;

Adjusting Matrix Size

For different matrix sizes, modify:

#define WIDTH your_width
#define HEIGHT your_height

Memory Usage

This example uses approximately:

• 30KB for LED buffer (100x100 RGB)
• 2KB for FFT data
• 1KB for audio buffers
• Additional memory for effect buffers

Troubleshooting

• No visualization: Check audio input and "Enable Audio" setting
• Choppy animation: Reduce matrix size or disable some features
• No beat detection: Increase beat sensitivity or check audio levels
• Dim display: Increase brightness or check power supply
• Compilation error: Ensure platform has sufficient memory

Credits

This example demonstrates the audio processing capabilities of FastLED, including FFT analysis, beat detection, and various visualization techniques suitable for LED art installations, music visualizers, and interactive displays.