flutter_fft 1.0.2+6

Pitch detection plugin, made for my personal project. Makes use of platform channels (currently Android only) in order to process audio in real-time and give feedback.

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter_fft/flutter_fft.dart';

void main() => runApp(Application());

class Application extends StatefulWidget {
  @override
  ApplicationState createState() => ApplicationState();
}

class ApplicationState extends State<Application> {
  double? frequency;
  String? note;
  int? octave;
  bool? isRecording;

  FlutterFft flutterFft = new FlutterFft();

  _initialize() async {
    print("Starting recorder...");
    // print("Before");
    // bool hasPermission = await flutterFft.checkPermission();
    // print("After: " + hasPermission.toString());

    // Keep asking for mic permission until accepted
    while (!(await flutterFft.checkPermission())) {
      flutterFft.requestPermission();
      // IF DENY QUIT PROGRAM
    }

    // await flutterFft.checkPermissions();
    await flutterFft.startRecorder();
    print("Recorder started...");
    setState(() => isRecording = flutterFft.getIsRecording);

    flutterFft.onRecorderStateChanged.listen(
        (data) => {
              print("Changed state, received: $data"),
              setState(
                () => {
                  frequency = data[1] as double,
                  note = data[2] as String,
                  octave = data[5] as int,
                },
              ),
              flutterFft.setNote = note!,
              flutterFft.setFrequency = frequency!,
              flutterFft.setOctave = octave!,
              print("Octave: ${octave!.toString()}")
            },
        onError: (err) {
          print("Error: $err");
        },
        onDone: () => {print("Isdone")});
  }

  @override
  void initState() {
    isRecording = flutterFft.getIsRecording;
    frequency = flutterFft.getFrequency;
    note = flutterFft.getNote;
    octave = flutterFft.getOctave;
    super.initState();
    _initialize();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
        title: "Simple flutter fft example",
        theme: ThemeData.dark(),
        color: Colors.blue,
        home: Scaffold(
          backgroundColor: Colors.purple,
          body: Center(
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                isRecording!
                    ? Text("Current note: ${note!},${octave!.toString()}",
                        style: TextStyle(fontSize: 30))
                    : Text("Not Recording", style: TextStyle(fontSize: 35)),
                isRecording!
                    ? Text(
                        "Current frequency: ${frequency!.toStringAsFixed(2)}",
                        style: TextStyle(fontSize: 30))
                    : Text("Not Recording", style: TextStyle(fontSize: 35))
              ],
            ),
          ),
        ));
  }
}