画像ラベル判定のサンプルコード

main.dart

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:firebase_ml_vision/firebase_ml_vision.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final BarcodeDetector barcodeDetector = FirebaseVision.instance.barcodeDetector();
  final FaceDetector faceDetector = FirebaseVision.instance.faceDetector();
  final ImageLabeler imageLabeler = FirebaseVision.instance.imageLabeler();

  File _image;
  List<Barcode> _barcodes;
  List<Face>  _faces;
  List<ImageLabel> _imageLabels;

  getImageFromGallary() {
    getImage(ImageSource.gallery);
  }

  getImageFromCamera() {
    getImage(ImageSource.camera);
  }

  Future getImage(ImageSource source) async {
    var image = await ImagePicker.pickImage(source: source);

    setState((){
      _image = image;
    });


    // 取得した画像を元に機械学習の推論を実行する

    if (image != null) {
      // 画像ファイル形式をFirebaseVisionImageに変換
      FirebaseVisionImage visionImage = FirebaseVisionImage.fromFile(image);
      // 画像からバーコードを検出
      List<Barcode> barcodes = await barcodeDetector.detectInImage(visionImage);
      if (barcodes.length > 0) {
        // バーコードの読み取り結果を格納
        setState(() => _barcodes = barcodes);
      }
      // 画像から顔を検出
      List<Face> faces = await faceDetector.processImage(visionImage);
      if (faces.length > 0) {
        // 顔の検出結果を格納
        setState(() => _faces = faces);
      }
      // 画像のラベル判定
      List<ImageLabel> imageLabels = await imageLabeler.processImage(visionImage);
      if (imageLabels.length > 0) {
        setState( () => _imageLabels = imageLabels);
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    String result = '<結果>\n';

    // バーコードの認識結果
    if (_barcodes != null && _barcodes.length > 0) {
      result += 'バーコードの認識結果: ';
      _barcodes.forEach((barcode) {
        result += barcode.displayValue + ", ";
      });
      result += '\n';
    }
    if (_faces != null && _faces.length > 0) {
      result += '顔の認識結果: ';
      _faces.forEach((face) {
        var boundingBox = face.boundingBox;
        result += boundingBox.toString() + ', ';
      });
      result += '\n';
    }
    if (_imageLabels != null && _imageLabels.length > 0) {
      result += '画像ラベルの判定結果: ';
      _imageLabels.forEach((imageLabel) {
        result +=  imageLabel.text + '${imageLabel.confidence}, ';
      });
      result += '\n';
    }
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: ListView(children: <Widget>[
        Center(
          child: _image == null ? Text('画像が選択されていません'):
            Image.file(_image)
        ),
        Text(
        result,
        overflow: TextOverflow.ellipsis,
        maxLines: 6
        ),
      ]),
      floatingActionButton: Column(
        crossAxisAlignment: CrossAxisAlignment.end,
        mainAxisAlignment: MainAxisAlignment.end,
        children: <Widget> [
          FloatingActionButton(
            onPressed: getImageFromCamera,
            tooltip: 'カメラ撮影',
            child:
            Icon(Icons.add_a_photo),
          ),
          FloatingActionButton(
            onPressed: getImageFromGallary,
            tooltip: '写真',
            child:
            Icon(Icons.photo_album),
          ),

        ],
      ),
    );
  }

}