如何将摄像头包录制的视频保存到Flutter中的图库？

import 'package:flutter/material.dart';
import 'package:camera/camera.dart';
import 'package:flutter_gallery_saver/flutter_gallery_saver.dart';

List<CameraDescription> cameras;

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  cameras = await availableCameras();
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Camera Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: CameraPage(),
    );
  }
}

class CameraPage extends StatefulWidget {
  @override
  _CameraPageState createState() => _CameraPageState();
}

class _CameraPageState extends State<CameraPage> {
  CameraController _controller;
  Future<void> _initializeControllerFuture;

  @override
  void initState() {
    super.initState();
    _controller = CameraController(
      cameras[0],
      ResolutionPreset.medium,
    );
    _initializeControllerFuture = _controller.initialize();
  }

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  void _startRecording() async {
    if (!_controller.value.isRecordingVideo) {
      await _initializeControllerFuture;
      final path = '/path/to/save/video.mp4';
      await _controller.startVideoRecording(path);
    }
  }

  void _stopRecording() async {
    if (_controller.value.isRecordingVideo) {
      await _controller.stopVideoRecording();
      final path = '/path/to/save/video.mp4';
      await FlutterGallerySaver.saveVideo(path: path);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Camera Demo'),
      ),
      body: FutureBuilder<void>(
        future: _initializeControllerFuture,
        builder: (context, snapshot) {
          if (snapshot.connectionState == ConnectionState.done) {
            return CameraPreview(_controller);
          } else {
            return Center(child: CircularProgressIndicator());
          }
        },
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _controller.value.isRecordingVideo ? _stopRecording : _startRecording,
        child: Icon(_controller.value.isRecordingVideo ? Icons.stop : Icons.fiber_manual_record),
      ),
    );
  }
}