pitchupdart 0.0.6

This library can be used to implement your own instrument tuning app.

example/example.md

import 'dart:typed_data';

import 'package:buffered_list_stream/buffered_list_stream.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:pitch_detector_dart/pitch_detector.dart';
import 'package:pitchupdart/pitch_handler.dart';
import 'package:pitchupdart/tuning_status.dart';
import 'package:pitchupfluttersample/home/tunning_state.dart';
import 'package:record/record.dart';

class PitchCubit extends Cubit<TunningState> {

  final AudioRecorder _audioRecorder;
  final PitchDetector _pitchDetectorDart;
  final PitchHandler _pitchupDart;

  PitchCubit(this._audioRecorder, this._pitchDetectorDart, this._pitchupDart):
   super(TunningState(note: "N/A", status: "Play something")) {
    _init();
  }

  _init() async {

    final recordStream = await _audioRecorder.startStream(
      const RecordConfig(
        encoder: AudioEncoder.pcm16bits,
        numChannels: 1,
        bitRate: 128000,
        sampleRate: PitchDetector.DEFAULT_SAMPLE_RATE,
      )
    );

    var audioSampleBufferedStream = bufferedListStream(
      recordStream.map((event) {
        return event.toList();
      }),
      //The library converts a PCM16 to 8bits internally. So we need twice as many bytes
      PitchDetector.DEFAULT_BUFFER_SIZE * 2,
      ) ;

    await for (var audioSample in audioSampleBufferedStream) {
      final intBuffer = Uint8List.fromList(audioSample);

      _pitchDetectorDart.getPitchFromIntBuffer(intBuffer).then((detectedPitch) {
        if (detectedPitch.pitched) {
           _pitchupDart.handlePitch(detectedPitch.pitch).then((pitchResult) => {
            
            emit(TunningState(
              note: pitchResult.note,
              status: pitchResult.tuningStatus.getDescription(),
            ))       
          });
        }
      });      
    }    
  }
}

extension Description on TuningStatus {
  
  String getDescription() =>
    switch(this) {
      TuningStatus.tuned => "Tuned",
      TuningStatus.toolow => "Too low. Tighten the string",
      TuningStatus.toohigh => "Too hig. Give it some slack",
      TuningStatus.waytoolow => "Way too low. Tighten the string",
      TuningStatus.waytoohigh => "Way to high. Give it some slack",
      TuningStatus.undefined => "Note is not in the valid interval.",
    };
  }