A Flutter package for real-time audio visualization using FFT (Fast Fourier Transform). This package captures audio input and displays it as an animated waveform using fl_chart.
Features
Real-time audio capture and frequency analysis
Customizable frequency spectrum ranges
Smooth animated waveform visualization
Support for different sample rates and buffer sizes
Easy-to-use API
Getting Started
Installation
Add this to your package's pubspec.yaml file:
dependencies:waveform_fft:^0.0.1
Platform Setup
Android
Add the following permissions to your android/app/src/main/AndroidManifest.xml:
Add the following keys to your ios/Runner/Info.plist:
<key>NSMicrophoneUsageDescription</key><string>This app needs access to microphone to visualize audio.</string>
Customizing the Waveform
The WaveFormWidgetEq widget accepts several parameters for customization:
WaveFormWidgetEq(
data: data, // Frequency data
animationDuration: Duration(milliseconds: 200), // Animation speed
updateInterval: Duration(milliseconds: 48), // Update frequency
barWidth: 5.0, // Width of each bar
maxY: 80.0, // Maximum Y value
minY: -80.0, // Minimum Y value
barColor: Colors.white, // Color of bars
barAlpha: 0.5, // Opacity of bars
);
Audio Capture Service
The AudioCaptureService can be customized with different sample rates and buffer sizes:
final service = AudioCaptureService(
sampleRate: 44100, // Default: 44100 Hz
bufferSize: 256, // Default: 256 samples
);
Note: The AudioCaptureService is a singleton and should be initialized once in your application.
Example
Here's a demo of the audio visualization in action:
The example above demonstrates:
Real-time audio capture from device microphone
FFT processing of audio data
Animated waveform visualization
Responsive UI with start/stop recording controls
Check out the complete example code in the /example directory to see how to implement this in your app.
Frequency Spectrum
The package includes predefined frequency spectrum ranges from 0Hz to 22kHz, following standard audio frequency bands. You can customize these ranges by modifying the AudioWaveFormConstants.defaultFrequencySpectrum.
Performance Considerations
Higher sample rates provide better frequency resolution but require more processing power
Smaller buffer sizes reduce latency but may cause performance issues
Consider device capabilities when adjusting these parameters
Compatibility
Android: API 21+
iOS: iOS 13.0+
If you do not want to use raw audio data by microphone then you can use any other flutter package like record or flutter_sound etc for audio recording purpose.
