viz

main.dart

import 'dart:ffi';
import 'dart:async';
import 'dart:math' as math;
import 'dart:typed_data';

import 'package:flutter/material.dart';
import 'package:english_words/english_words.dart';
import "dart:math";
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:lottie/lottie.dart';
import 'package:record/record.dart';
import 'package:mic_stream/mic_stream.dart';

String fullSubtitle = "hello";

double mapValue(
    double x, double inMin, double inMax, double outMin, double outMax) {
  return (x - inMin) * (outMax - outMin) / (inMax - inMin) + outMin;
}

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        brightness: Brightness.light,
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      darkTheme: ThemeData(
        brightness: Brightness.dark,
        /* dark theme settings */
      ),
      themeMode: ThemeMode.dark,
      home: const MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> with TickerProviderStateMixin {
  int _counter = 0;

  final _record = AudioRecorder();
  double minDecibels = -15;
  double maxDecibels = -4.6;
  double currentDecibels = -90.0;
  double currentLoudness = 0.0;

  double _ema_loudness = 0.0;
  double _ema_N = 5;

  int randomAnimChunk = 0;
  double frameMax = 300;
  late List<List<double>> animTimestampArray;

  late final AnimationController _controller;
  final random = Random();
  bool shouldChangeChunk = false;

  @override
  void initState() {
    super.initState();

    _controller = AnimationController(vsync: this);
    _controller.addListener(() {
      //print(_controller.value);
    });

    animTimestampArray = List.generate(3, (_) => List.filled(2, 0.0));
    animTimestampArray[0][0] = 0;
    animTimestampArray[0][1] = 29;
    animTimestampArray[1][0] = 44;
    animTimestampArray[1][1] = 74;
    animTimestampArray[2][0] = 161;
    animTimestampArray[2][1] = 179;
  }

  Future<void> _startRecord() async {
    print("_startRecord");
    if (!await _record.hasPermission()) {
      print("don't have permission");
      return;
    }

    final stream = await _record.startStream(
      const RecordConfig(
        encoder: AudioEncoder.pcm16bits,
      ),
    );

    stream.listen(
      (event) {
        currentLoudness = calculateLoudness(event);
        //print("currentLoudness: " + currentLoudness.toString());
        //_controller.value = currentLoudness * 0.27 / 1.0;
        if (currentLoudness > 0.1) {
          double rangeStart = animTimestampArray[randomAnimChunk][0];
          double rangeEnd = animTimestampArray[randomAnimChunk][1];

          print("randomAnimChunk: " + randomAnimChunk.toString());

          double animTargetFrame =
              mapValue(currentLoudness, 0, 1, rangeStart, rangeEnd);
          double animTargetFloat = mapValue(animTargetFrame, 0, frameMax, 0, 1);

          _controller.animateTo(animTargetFloat);
          setState(() {
            shouldChangeChunk = true;
          });
        } else {
          if (shouldChangeChunk) {
            setState(() {
              randomAnimChunk = random.nextInt(3);
              shouldChangeChunk = false;
              print("change anim chunk to :" + randomAnimChunk.toString());

              // Jump to start frame of new anim section.
              _controller.value = mapValue(
                  animTimestampArray[randomAnimChunk][0], 0, frameMax, 0, 1);
            });
          }
        }
      },
      onDone: () {},
    );
  }

  void startSubtibleFetchingLoop() {
    void loop() {
      // Generate a random delay between 1 and 3 seconds
      final randomSeconds = 0.2 + random.nextDouble();
      final randomDuration =
          Duration(milliseconds: (randomSeconds * 1000).round());

      setState(() {
        fullSubtitle += " " + all[Random().nextInt(all.length)];
      });
      // Print a message with the current time

      //print(fullSubtitle);

      // Schedule the next iteration of the loop after the random delay
      Future.delayed(randomDuration, loop);
    }

    // Start the loop for the first time
    loop();
  }

  double calculateDecibels(Uint8List event) {
    var samples = Int16List.view(event.buffer);

    // Calculate RMS
    double sumOfSquares = 0.0;
    for (var sample in samples) {
      sumOfSquares += math.pow(sample, 2).toDouble();
    }
    double rms = math.sqrt(sumOfSquares / samples.length);
    rms = math.max(rms, 1.0);

    double db = 20 * math.log(rms / 32768.0) / math.ln10;
    db = math.max(db, -80.0);

    return db;
  }

  double calculateLoudness(Uint8List event) {
    final db = calculateDecibels(event);
    //print(db);

    double clampedDbfs = db.clamp(minDecibels, maxDecibels);

    double normalized =
        (clampedDbfs - minDecibels) / (maxDecibels - minDecibels);

    double loudness = math.pow(normalized, 16).toDouble();

    double k = 2 / (_ema_N + 1);

    setState(() {
      _ema_loudness = loudness * k + _ema_loudness * (1 - k);
    });

    return _ema_loudness;
  }

  void _incrementCounter() {
    //startSubtibleFetchingLoop();
    _startRecord();
    _controller.value = 0;
    //_controller.animateTo(1.0);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        // TRY THIS: Try changing the color here to a specific color (to
        // Colors.amber, perhaps?) and trigger a hot reload to see the AppBar
        // change color while the other colors stay the same.
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              fullSubtitle,
              style: TextStyle(fontSize: 20),
            ),
            Lottie.asset(
              'assets/Circular Visualizer Podcast 1.json',
              controller: _controller,
              onLoaded: (composition) {
                // Configure the AnimationController with the duration of the
                // Lottie file and start the animation.
                _controller
                  ..duration = composition.duration
                  ..forward();
              },
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Start subtitle',
        child: const Icon(Icons.start),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}