Implement Real-time Audio Input Processing

[pbalduino]

Description

Replace fake sample data with actual microphone input and real-time frequency detection

Priority

🔴 High

Category

Core Functionality

Details

• Add microphone permission handling
• Integrate real-time frequency detection using FFT + autocorrelation
• Apply noise filtering <2kHz as recommended in requirements
• Replace static frequency values in tuner_screen.dart:163-168

Files Affected

• lib/screens/tuner_screen.dart
• pubspec.yaml (add audio dependencies)

Acceptance Criteria

• App requests microphone permission on first use
• Real-time frequency detection works accurately
• Noise filtering reduces false readings
• Audio processing pauses when app is backgrounded

Task ID: AUDIO-001

[pbalduino]

✅ Completed!

Real-time audio input processing has been successfully implemented:

• ✅ Added microphone permission handling
• ✅ Integrated real-time frequency detection using FFT + autocorrelation
• ✅ Applied noise filtering for cleaner readings
• ✅ Replaced static frequency values with live audio processing
• ✅ Audio processing pauses when app is backgrounded
• ✅ Added proper lifecycle management

Key Features Implemented:

• service with implementation
• Real-time frequency analysis with automatic string detection
• Amplitude-based signal validation
• Permission handling with user-friendly error messages
• Background/foreground state management
• Manual vs automatic string selection modes

Dependencies Added:

The tuner now provides real-time, accurate frequency detection for all supported instruments! 🎸