camera 0.5.4

Camera Plugin #

pub package

A Flutter plugin for iOS and Android allowing access to the device cameras.

Note: This plugin is still under development, and some APIs might not be available yet. We are working on a refactor which can be followed here: issue

Features: #

  • Display live camera preview in a widget.
  • Snapshots can be captured and saved to a file.
  • Record video.
  • Add access to the image stream from Dart.

Installation #

First, add camera as a dependency in your pubspec.yaml file.

iOS #

Add two rows to the ios/Runner/Info.plist:

  • one with the key Privacy - Camera Usage Description and a usage description.
  • and one with the key Privacy - Microphone Usage Description and a usage description.

Or in text format add the key:

<key>NSCameraUsageDescription</key>
<string>Can I use the camera please?</string>
<key>NSMicrophoneUsageDescription</key>
<string>Can I use the mic please?</string>

Android #

Change the minimum Android sdk version to 21 (or higher) in your android/app/build.gradle file.

minSdkVersion 21

Example #

Here is a small example flutter app displaying a full screen camera preview.

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

List<CameraDescription> cameras;

Future<void> main() async {
  cameras = await availableCameras();
  runApp(CameraApp());
}

class CameraApp extends StatefulWidget {
  @override
  _CameraAppState createState() => _CameraAppState();
}

class _CameraAppState extends State<CameraApp> {
  CameraController controller;

  @override
  void initState() {
    super.initState();
    controller = CameraController(cameras[0], ResolutionPreset.medium);
    controller.initialize().then((_) {
      if (!mounted) {
        return;
      }
      setState(() {});
    });
  }

  @override
  void dispose() {
    controller?.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    if (!controller.value.isInitialized) {
      return Container();
    }
    return AspectRatio(
        aspectRatio:
        controller.value.aspectRatio,
        child: CameraPreview(controller));
  }
}

For a more elaborate usage example see here.

Note: This plugin is still under development, and some APIs might not be available yet. Feedback welcome and Pull Requests are most welcome!

0.5.4 #

  • Add feature to pause and resume video recording.

0.5.3+1 #

  • Fix too large request code for FragmentActivity users.

0.5.3 #

  • Added new quality presets.
  • Now all quality presets can be used to control image capture quality.

0.5.2+2 #

  • Fix memory leak related to not unregistering stream handler in FlutterEventChannel when disposing camera.

0.5.2+1 #

  • Fix bug that prevented video recording with audio.

0.5.2 #

  • Added capability to disable audio for the CameraController. (e.g. CameraController(_, _, enableAudio: false);)

0.5.1 #

  • Can now be compiled with earlier Android sdks below 21 when <uses-sdk tools:overrideLibrary="io.flutter.plugins.camera"/> has been added to the project AndroidManifest.xml. For sdks below 21, the plugin won't be registered and calls to it will throw a MissingPluginException.

0.5.0 #

  • Breaking Change This plugin no longer handles closing and opening the camera on Android lifecycle changes. Please use WidgetsBindingObserver to control camera resources on lifecycle changes. See example project for example using WidgetsBindingObserver.

0.4.3+2 #

  • Bump the minimum Flutter version to 1.2.0.
  • Add template type parameter to invokeMethod calls.

0.4.3+1 #

  • Catch additional Exceptions from Android and throw as CameraExceptions.

0.4.3 #

  • Add capability to prepare the capture session for video recording on iOS.

0.4.2 #

  • Add sensor orientation value to CameraDescription.

0.4.1 #

  • Camera methods are ran in a background thread on iOS.

0.4.0+3 #

  • Fixed a crash when the plugin is registered by a background FlutterView.

0.4.0+2 #

  • Fix orientation of captured photos when camera is used for the first time on Android.

0.4.0+1 #

  • Remove categories.

0.4.0 #

  • Breaking Change Change iOS image stream format to ImageFormatGroup.bgra8888 from ImageFormatGroup.yuv420.

0.3.0+4 #

  • Fixed bug causing black screen on some Android devices.

0.3.0+3 #

  • Log a more detailed warning at build time about the previous AndroidX migration.

0.3.0+2 #

  • Fix issue with calculating iOS image orientation in certain edge cases.

0.3.0+1 #

  • Remove initial method call invocation from static camera method.

0.3.0 #

  • Breaking change. Migrate from the deprecated original Android Support Library to AndroidX. This shouldn't result in any functional changes, but it requires any Android apps using this plugin to also migrate if they're using the original support library.

0.2.9+1 #

  • Fix a crash when failing to start preview.

0.2.9 #

  • Save photo orientation data on iOS.

0.2.8 #

  • Add access to the image stream from Dart.
  • Use cameraController.startImageStream(listener) to process the images.

0.2.7 #

  • Fix issue with crash when the physical device's orientation is unknown.

0.2.6 #

  • Update the camera to use the physical device's orientation instead of the UI orientation on Android.

0.2.5 #

  • Fix preview and video size with satisfying conditions of multiple outputs.

0.2.4 #

  • Unregister the activity lifecycle callbacks when disposing the camera.

0.2.3 #

  • Added path_provider and video_player as dev dependencies because the example uses them.
  • Updated example path_provider version to get Dart 2 support.

0.2.2 #

  • iOS image capture is done in high quality (full camera size)

0.2.1 #

  • Updated Gradle tooling to match Android Studio 3.1.2.

0.2.0 #

  • Added support for video recording.
  • Changed the example app to add video recording.

A lot of breaking changes in this version:

Getter changes:

  • Removed isStarted
  • Renamed initialized to isInitialized
  • Added isRecordingVideo

Method changes:

  • Renamed capture to takePicture
  • Removed start (the preview starts automatically when initialize is called)
  • Added startVideoRecording(String filePath)
  • Removed stop (the preview stops automatically when dispose is called)
  • Added stopVideoRecording

0.1.2 #

  • Fix Dart 2 runtime errors.

0.1.1 #

  • Fix Dart 2 runtime error.

0.1.0 #

  • Breaking change. Set SDK constraints to match the Flutter beta release.

0.0.4 #

  • Revert regression of CameraController.capture() introduced in v. 0.0.3.

0.0.3 #

  • Improved resource cleanup on Android. Avoids crash on Activity restart.
  • Made the Future returned by CameraController.dispose() and CameraController.capture() actually complete on Android.

0.0.2 #

  • Simplified and upgraded Android project template to Android SDK 27.
  • Moved Android package to io.flutter.plugins.
  • Fixed warnings from the Dart 2.0 analyzer.

0.0.1 #

  • Initial release

example/lib/main.dart

// Copyright 2019 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:async';
import 'dart:io';

import 'package:camera/camera.dart';
import 'package:flutter/material.dart';
import 'package:path_provider/path_provider.dart';
import 'package:video_player/video_player.dart';

class CameraExampleHome extends StatefulWidget {
  @override
  _CameraExampleHomeState createState() {
    return _CameraExampleHomeState();
  }
}

/// Returns a suitable camera icon for [direction].
IconData getCameraLensIcon(CameraLensDirection direction) {
  switch (direction) {
    case CameraLensDirection.back:
      return Icons.camera_rear;
    case CameraLensDirection.front:
      return Icons.camera_front;
    case CameraLensDirection.external:
      return Icons.camera;
  }
  throw ArgumentError('Unknown lens direction');
}

void logError(String code, String message) =>
    print('Error: $code\nError Message: $message');

class _CameraExampleHomeState extends State<CameraExampleHome>
    with WidgetsBindingObserver {
  CameraController controller;
  String imagePath;
  String videoPath;
  VideoPlayerController videoController;
  VoidCallback videoPlayerListener;
  bool enableAudio = true;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    // App state changed before we got the chance to initialize.
    if (controller == null || !controller.value.isInitialized) {
      return;
    }
    if (state == AppLifecycleState.inactive) {
      controller?.dispose();
    } else if (state == AppLifecycleState.resumed) {
      if (controller != null) {
        onNewCameraSelected(controller.description);
      }
    }
  }

  final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      key: _scaffoldKey,
      appBar: AppBar(
        title: const Text('Camera example'),
      ),
      body: Column(
        children: <Widget>[
          Expanded(
            child: Container(
              child: Padding(
                padding: const EdgeInsets.all(1.0),
                child: Center(
                  child: _cameraPreviewWidget(),
                ),
              ),
              decoration: BoxDecoration(
                color: Colors.black,
                border: Border.all(
                  color: controller != null && controller.value.isRecordingVideo
                      ? Colors.redAccent
                      : Colors.grey,
                  width: 3.0,
                ),
              ),
            ),
          ),
          _captureControlRowWidget(),
          _toggleAudioWidget(),
          Padding(
            padding: const EdgeInsets.all(5.0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.start,
              children: <Widget>[
                _cameraTogglesRowWidget(),
                _thumbnailWidget(),
              ],
            ),
          ),
        ],
      ),
    );
  }

  /// Display the preview from the camera (or a message if the preview is not available).
  Widget _cameraPreviewWidget() {
    if (controller == null || !controller.value.isInitialized) {
      return const Text(
        'Tap a camera',
        style: TextStyle(
          color: Colors.white,
          fontSize: 24.0,
          fontWeight: FontWeight.w900,
        ),
      );
    } else {
      return AspectRatio(
        aspectRatio: controller.value.aspectRatio,
        child: CameraPreview(controller),
      );
    }
  }

  /// Toggle recording audio
  Widget _toggleAudioWidget() {
    return Padding(
      padding: const EdgeInsets.only(left: 25),
      child: Row(
        children: <Widget>[
          const Text('Enable Audio:'),
          Switch(
            value: enableAudio,
            onChanged: (bool value) {
              enableAudio = value;
              if (controller != null) {
                onNewCameraSelected(controller.description);
              }
            },
          ),
        ],
      ),
    );
  }

  /// Display the thumbnail of the captured image or video.
  Widget _thumbnailWidget() {
    return Expanded(
      child: Align(
        alignment: Alignment.centerRight,
        child: Row(
          mainAxisSize: MainAxisSize.min,
          children: <Widget>[
            videoController == null && imagePath == null
                ? Container()
                : SizedBox(
                    child: (videoController == null)
                        ? Image.file(File(imagePath))
                        : Container(
                            child: Center(
                              child: AspectRatio(
                                  aspectRatio:
                                      videoController.value.size != null
                                          ? videoController.value.aspectRatio
                                          : 1.0,
                                  child: VideoPlayer(videoController)),
                            ),
                            decoration: BoxDecoration(
                                border: Border.all(color: Colors.pink)),
                          ),
                    width: 64.0,
                    height: 64.0,
                  ),
          ],
        ),
      ),
    );
  }

  /// Display the control bar with buttons to take pictures and record videos.
  Widget _captureControlRowWidget() {
    return Row(
      mainAxisAlignment: MainAxisAlignment.spaceEvenly,
      mainAxisSize: MainAxisSize.max,
      children: <Widget>[
        IconButton(
          icon: const Icon(Icons.camera_alt),
          color: Colors.blue,
          onPressed: controller != null &&
                  controller.value.isInitialized &&
                  !controller.value.isRecordingVideo
              ? onTakePictureButtonPressed
              : null,
        ),
        IconButton(
          icon: const Icon(Icons.videocam),
          color: Colors.blue,
          onPressed: controller != null &&
                  controller.value.isInitialized &&
                  !controller.value.isRecordingVideo
              ? onVideoRecordButtonPressed
              : null,
        ),
        IconButton(
          icon: controller != null && controller.value.isRecordingPaused
              ? Icon(Icons.play_arrow)
              : Icon(Icons.pause),
          color: Colors.blue,
          onPressed: controller != null &&
                  controller.value.isInitialized &&
                  controller.value.isRecordingVideo
              ? (controller != null && controller.value.isRecordingPaused
                  ? onResumeButtonPressed
                  : onPauseButtonPressed)
              : null,
        ),
        IconButton(
          icon: const Icon(Icons.stop),
          color: Colors.red,
          onPressed: controller != null &&
                  controller.value.isInitialized &&
                  controller.value.isRecordingVideo
              ? onStopButtonPressed
              : null,
        )
      ],
    );
  }

  /// Display a row of toggle to select the camera (or a message if no camera is available).
  Widget _cameraTogglesRowWidget() {
    final List<Widget> toggles = <Widget>[];

    if (cameras.isEmpty) {
      return const Text('No camera found');
    } else {
      for (CameraDescription cameraDescription in cameras) {
        toggles.add(
          SizedBox(
            width: 90.0,
            child: RadioListTile<CameraDescription>(
              title: Icon(getCameraLensIcon(cameraDescription.lensDirection)),
              groupValue: controller?.description,
              value: cameraDescription,
              onChanged: controller != null && controller.value.isRecordingVideo
                  ? null
                  : onNewCameraSelected,
            ),
          ),
        );
      }
    }

    return Row(children: toggles);
  }

  String timestamp() => DateTime.now().millisecondsSinceEpoch.toString();

  void showInSnackBar(String message) {
    _scaffoldKey.currentState.showSnackBar(SnackBar(content: Text(message)));
  }

  void onNewCameraSelected(CameraDescription cameraDescription) async {
    if (controller != null) {
      await controller.dispose();
    }
    controller = CameraController(
      cameraDescription,
      ResolutionPreset.medium,
      enableAudio: enableAudio,
    );

    // If the controller is updated then update the UI.
    controller.addListener(() {
      if (mounted) setState(() {});
      if (controller.value.hasError) {
        showInSnackBar('Camera error ${controller.value.errorDescription}');
      }
    });

    try {
      await controller.initialize();
    } on CameraException catch (e) {
      _showCameraException(e);
    }

    if (mounted) {
      setState(() {});
    }
  }

  void onTakePictureButtonPressed() {
    takePicture().then((String filePath) {
      if (mounted) {
        setState(() {
          imagePath = filePath;
          videoController?.dispose();
          videoController = null;
        });
        if (filePath != null) showInSnackBar('Picture saved to $filePath');
      }
    });
  }

  void onVideoRecordButtonPressed() {
    startVideoRecording().then((String filePath) {
      if (mounted) setState(() {});
      if (filePath != null) showInSnackBar('Saving video to $filePath');
    });
  }

  void onStopButtonPressed() {
    stopVideoRecording().then((_) {
      if (mounted) setState(() {});
      showInSnackBar('Video recorded to: $videoPath');
    });
  }

  void onPauseButtonPressed() {
    pauseVideoRecording().then((_) {
      if (mounted) setState(() {});
      showInSnackBar('Video recording paused');
    });
  }

  void onResumeButtonPressed() {
    resumeVideoRecording().then((_) {
      if (mounted) setState(() {});
      showInSnackBar('Video recording resumed');
    });
  }

  Future<String> startVideoRecording() async {
    if (!controller.value.isInitialized) {
      showInSnackBar('Error: select a camera first.');
      return null;
    }

    final Directory extDir = await getApplicationDocumentsDirectory();
    final String dirPath = '${extDir.path}/Movies/flutter_test';
    await Directory(dirPath).create(recursive: true);
    final String filePath = '$dirPath/${timestamp()}.mp4';

    if (controller.value.isRecordingVideo) {
      // A recording is already started, do nothing.
      return null;
    }

    try {
      videoPath = filePath;
      await controller.startVideoRecording(filePath);
    } on CameraException catch (e) {
      _showCameraException(e);
      return null;
    }
    return filePath;
  }

  Future<void> stopVideoRecording() async {
    if (!controller.value.isRecordingVideo) {
      return null;
    }

    try {
      await controller.stopVideoRecording();
    } on CameraException catch (e) {
      _showCameraException(e);
      return null;
    }

    await _startVideoPlayer();
  }

  Future<void> pauseVideoRecording() async {
    if (!controller.value.isRecordingVideo) {
      return null;
    }

    try {
      await controller.pauseVideoRecording();
    } on CameraException catch (e) {
      _showCameraException(e);
      return null;
    }
  }

  Future<void> resumeVideoRecording() async {
    if (!controller.value.isRecordingVideo) {
      return null;
    }

    try {
      await controller.resumeVideoRecording();
    } on CameraException catch (e) {
      _showCameraException(e);
      return null;
    }
  }

  Future<void> _startVideoPlayer() async {
    final VideoPlayerController vcontroller =
        VideoPlayerController.file(File(videoPath));
    videoPlayerListener = () {
      if (videoController != null && videoController.value.size != null) {
        // Refreshing the state to update video player with the correct ratio.
        if (mounted) setState(() {});
        videoController.removeListener(videoPlayerListener);
      }
    };
    vcontroller.addListener(videoPlayerListener);
    await vcontroller.setLooping(true);
    await vcontroller.initialize();
    await videoController?.dispose();
    if (mounted) {
      setState(() {
        imagePath = null;
        videoController = vcontroller;
      });
    }
    await vcontroller.play();
  }

  Future<String> takePicture() async {
    if (!controller.value.isInitialized) {
      showInSnackBar('Error: select a camera first.');
      return null;
    }
    final Directory extDir = await getApplicationDocumentsDirectory();
    final String dirPath = '${extDir.path}/Pictures/flutter_test';
    await Directory(dirPath).create(recursive: true);
    final String filePath = '$dirPath/${timestamp()}.jpg';

    if (controller.value.isTakingPicture) {
      // A capture is already pending, do nothing.
      return null;
    }

    try {
      await controller.takePicture(filePath);
    } on CameraException catch (e) {
      _showCameraException(e);
      return null;
    }
    return filePath;
  }

  void _showCameraException(CameraException e) {
    logError(e.code, e.description);
    showInSnackBar('Error: ${e.code}\n${e.description}');
  }
}

class CameraApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: CameraExampleHome(),
    );
  }
}

List<CameraDescription> cameras;

Future<void> main() async {
  // Fetch the available cameras before initializing the app.
  try {
    cameras = await availableCameras();
  } on CameraException catch (e) {
    logError(e.code, e.description);
  }
  runApp(CameraApp());
}

Use this package as a library

1. Depend on it

Add this to your package's pubspec.yaml file:


dependencies:
  camera: ^0.5.4

2. Install it

You can install packages from the command line:

with Flutter:


$ flutter pub get

Alternatively, your editor might support flutter pub get. Check the docs for your editor to learn more.

3. Import it

Now in your Dart code, you can use:


import 'package:camera/camera.dart';
  
Popularity:
Describes how popular the package is relative to other packages. [more]
99
Health:
Code health derived from static analysis. [more]
100
Maintenance:
Reflects how tidy and up-to-date the package is. [more]
90
Overall:
Weighted score of the above. [more]
97
Learn more about scoring.

We analyzed this package on Aug 22, 2019, and provided a score, details, and suggestions below. Analysis was completed with status completed using:

  • Dart: 2.4.0
  • pana: 0.12.19
  • Flutter: 1.7.8+hotfix.4

Platforms

Detected platforms: Flutter

References Flutter, and has no conflicting libraries.

Maintenance suggestions

The description is too long. (-10 points)

Search engines display only the first part of the description. Try to keep the value of the description field in your package's pubspec.yaml file between 60 and 180 characters.

Dependencies

Package Constraint Resolved Available
Direct dependencies
Dart SDK >=2.0.0-dev.28.0 <3.0.0
flutter 0.0.0
Transitive dependencies
collection 1.14.11 1.14.12
meta 1.1.6 1.1.7
sky_engine 0.0.99
typed_data 1.1.6
vector_math 2.0.8
Dev dependencies
flutter_driver
flutter_test
path_provider ^0.5.0
video_player ^0.10.0